Project Zomboid Build 42 Generator Load: The Fridge and Freezer Are the Only Standing Bill

Every guide that gets you as far as a running generator ends in the same place: open Generator Info, read the total, work the rest out yourself. Build 42.20 does publish those numbers — the load is real, it is itemised, and it is charged per tile rather than per appliance. But reading them properly overturns the budget most survivors arrive with.

The bill has a shape almost nobody documents. Exactly one class of appliance is charged for existing. A fridge or a freezer is billed the moment it sits inside the generator's circle, with no switch to flip and no door to keep shut, and there is no way to stop paying for it short of moving it out of range. Everything else — the oven, the microwave, the television, every light in the house — sits behind an activation flag and costs literally nothing until you press start. That one division quietly replaces the question you came with. It is not which of the five — fridge, freezer, oven, microwave, water — can I afford. It is how many cold-storage tiles are inside the circle, and the answer is usually two.

Follow the arithmetic to the end and the numbers are almost comically small. A fridge and a freezer together burn about half a litre a day, so a single gas can carries them roughly eighteen in-game days. An hour of oven time costs nine thousandths of a litre. The water plan the shutoff supposedly forces on you never appears on the bill at all, because nothing in Project Zomboid needs electricity to produce water. And the generator that was never going to run out of fuel will still destroy itself on schedule — because condition is spent by the hour whether or not anything is plugged in, and it reaches the band where the machine starts catching fire long before the gasoline was ever going to become your problem.

Generator Info Is an Itemised Bill, and It Has Already Applied the Multiplier

Right-click a running generator, choose Generator Info, and the game hands you something it is strangely quiet about everywhere else: an itemised receipt. Not a status light, not a fuel bar — a list of every object the generator is currently paying for, each one priced in litres per hour, with a total underneath. This is a real panel — PZwiki's own illustrative capture — from a base with a popsicle freezer, a television and six lamps inside the generator's reach:

Generator Info is the first entry on the generator’s right-click menu. This 2022 Build 41-era capture shows the menu itself, not the panel behind it; the entries are unchanged in Build 42.

Fuel 89% · Condition 98%

Four lines, and every one of them tells you something

Start with the fact that there are four lines at all. You will find it stated confidently, in more than one place, that Build 42 generator drain is a flat rate — that it comes out of a sandbox slider and has nothing to do with what you connect. That is wrong, and this panel is the disproof. The total is assembled object by object from what the generator found, and it moves when they move: switch off that television and the total drops by exactly 0.003. The load is real, it is itemised, and the game is showing you its working.

Second: Popsicle Freezer x2 is one freezer. The number after the name is not a count of appliances — it is a count of tiles. The game prices the load per object on each square inside the generator's reach, and a popsicle freezer is a two-tile appliance, so it is two objects and it is billed twice, at 0.008 each. The panel then groups identically-named entries together and shows you the tally, which is why a single freezer reads as x2 and six separate light switches read as x6 at 0.0002 apiece. The consequence is worth internalising before you read another line: when you compare two appliances, count their tiles first. Two appliances of the same class do not cost the same if one of them is twice as wide.

Third, and easy to skim past: the bottom entry. Gas-powered Generator (0.002 L/h) is the generator billing itself. Before the game counts a single appliance it starts the tally at the machine's own baseline, then adds whatever it finds on top — so a generator that is running with nothing else in range is still spending 0.002 L/h, which is 0.048 litres a day. On this particular panel that self-charge is about 9% of everything the base is spending. It is small, it is unavoidable while the unit is on, and it is one of the reasons a hand-rolled estimate never quite matches the panel.

Fourth, and this is the one that resolves most of the confusion around these numbers: 0.0222 is already the finished figure. There is a sandbox setting, GeneratorFuelConsumption, that scales the entire bill, and in Build 42 its default is 0.1. The game applies that multiplier in two places — when it subtracts fuel from the tank each hour, and when it renders this panel. So what you are looking at is not a raw value waiting to be converted. It is litres, actual litres, actually leaving the tank at your settings. The same is true of the per-tile rate tables published elsewhere: they are quoting the multiplied figures, not the underlying constants. Nothing you read on this screen needs adjusting before you use it.

From the total to a runtime

Which makes the arithmetic a single division. The tank is exactly 10.0 litres — exactly one Gas Can, no more and no half-measures, and there is no siphoning any of it back out — so a full tank is always the same ten litres. Runtime from full is 10 ÷ the panel's total:

10 ÷ 0.0222 = 450 in-game hours, or a little under 19 in-game days.

That is the figure for a full can. The panel above reads Fuel 89%, so this particular machine has nearer 400 hours left in it, not 450 — the divisor is the panel's total, and the numerator is whatever is actually in the tank.

Every hour and every day in this article is an in-game one. Real time depends on your day-length setting and has nothing to do with the fuel model.

That division holds as long as the dials it rests on are where the game put them. Everything here assumes Build 42's sandbox defaults: GeneratorFuelConsumption at 0.1, GeneratorTileRange at 20, GeneratorVerticalPowerRange at 3, AllowExteriorGenerator on, and the default FridgeFactor. Those five are the only settings that can move any number in this guide. If you are on a server or a custom preset that changed one of them, your own panel is still telling you the truth — it is the day counts here that stop applying, and the division is how you rebuild them.

The bill only exists after the shutoff

One more piece of framing, because it decides what the whole bill is for. This is all post-shutoff arithmetic. While the grid is up, the generator sits switched off and costs nothing; it has no job. The moment mains power dies, perishable food in every refrigerated container in the world starts rotting — not just yours, everywhere, all at once — and the only exemption on offer is a running generator. That is what the panel actually is: the list of things that currently hold that exemption, and what you are paying per hour to keep them on it.

So stop estimating. Open the panel, read the total, divide 10 by it, and you have your runtime in in-game hours. Then do the part most people skip and read the lines above the total, because if an entry surprises you, the surprise is the useful part — the total is only the sum of things you should already be able to name.

And that is the catch buried in this panel. It never asked what you intended to power. It lists what it found.

Every Object Inside the Circle Is on the Bill, Plugged In or Not

There is no plugging in. That sounds like pedantry until you go looking for the verb and cannot find it — Project Zomboid has no cable, no socket, no per-appliance hookup, and no menu anywhere that lets you tell a generator this fridge, not that one. What it has instead is a scan. Once an hour the generator throws away its running total, resets it to its own baseline, and walks the squares around itself looking for objects it recognises. Everything it recognises becomes a line on the panel. That is the whole membership test, and nothing you intended enters into it.

The shape it walks is a circle, and specifically a circle rather than the square a lazier implementation would have given you. The scan takes a box twenty tiles out in each direction, then tests every square in that box against the generator's position by squared distance and throws away anything further out than the radius. At the default of twenty that leaves a disc 41 tiles across — twenty out, the generator's own square, twenty back — and somewhere around 1,250 squares on every level it reaches. The corners a square-shaped rule would have swept in are excluded, which is the one place where the reach is smaller than people assume.

It is also the same disc on all four generators. Lectro-Max, Premium Technologies, ValuTech and the Old unit differ in weight, in how loudly they run and in how fast they wear out, and those differences are worth caring about — but not one of them touches the powered area. There is no premium model that reaches further.

Downward, the reach is settled, and it is the direction that catches people. The Build 42 changelogs fixed the same area twice: 42.1.0 fixed generators not powering things below ground at all, and 42.12.0 fixed "electrics in basements not impacting generator fuel consumption" — which is to say a basement fridge used to be kept cold for free and now correctly appears on the bill. A cellar you have not opened since you moved in is inside the cylinder.

Upward is where the honest answer is that nobody has settled it. PZwiki describes a cylinder of height seven — three floors up, three down. The Build 42.13.2 code contains two pieces that disagree with each other at the top. The square-walk itself runs for z = minZ; z < maxZ, an exclusive bound, which covers three floors down and only two up; the sibling helper isPoweringSquare, which answers the same question elsewhere, uses an inclusive <= and so gives three and three. Build 41 carries the same exclusive bound, so this is old, not a Build 42 regression. What is certain is the sandbox option: GeneratorVerticalPowerRange, default 3. Treat the lower half of that range as dependable and the very top floor of it as something to test rather than trust — and the test takes seconds, because you already have the instrument. Put a light switch or a fridge on the floor in question, open Generator Info, and see whether a line appears. The panel settles it for your save in a way no wiki page can.

Both dimensions became yours to change in 42.8.0, which added GeneratorTileRange (default 20, settable 1–100) and GeneratorVerticalPowerRange (default 3, settable 1–15) specifically "to support generator use in tall and deep buildings". Build 41 hardcoded both. They took several builds to behave: 42.9.0 raised the vertical cap from 10 to 15 and fixed the tile range not working above 20, 42.11.0 fixed the range not being reapplied when a save loaded, and 42.19.0 fixed severe performance problems at high values. If you are on a server, find out what these are set to before you trust any radius — someone who set the tile range to 60 because it sounded generous has not made the disc slightly bigger, they have made it 121 tiles across and swallowed half the street.

Which is what the audit is for. A generator standing in the yard of an ordinary house reaches twenty tiles in every direction, and twenty tiles is far more house than it sounds: the building, the garage, the shed at the back, the cellar underneath, and a good share of whatever is on the other side of the fence. Your neighbours' kitchens are inside your disc.

So read the panel line by line and put a name to every entry. Popsicle Freezer x2 should mean one freezer you know about, standing on two tiles. Lights x6 should mean six switches you could walk to. If an entry does not match anything you own, you have not misread the panel — you have found something, and the two usual culprits are the basement that came with the house and the house next door. A neighbour's fridge, well inside the disc through walls you have never opened, is billed at 0.013 L/h for as long as your generator runs, and there is nothing on it to switch off.

There are only two ways an object inside that disc stays off your bill. The first is distance — move the generator, or move the appliance, and the arithmetic follows. The second is that the square has no power to begin with: 42.8.0's notes state that light switches and electricity will not work in rooms whose room definition name contains "derelict", or in a no-power map zone. That is a single changelog line with no wiki page behind it, so hold it loosely — but if a building well inside your radius contributes nothing at all to the panel, a derelict room definition is the likeliest reason, and it is not a bug in your generator.

One setting can redraw the disc rather than resize it. AllowExteriorGenerator — "Generator Working In Exterior" — is checked per square as the scan runs, and it is on by default. Turned off, as some server presets do, every exterior square drops out of the walk entirely, taking with it anything standing outdoors.

The instinct to fight here is thinking of a generator as powering the house, because a house is the unit you think in. The game only thinks in squares and distances, and it has never once heard of your base. Audit the circle, not the room: reconcile every line on the panel against something you meant to power, and treat anything left over as a real cost, because a fridge under the floor and a fridge next door are charged at exactly the same rate as the one you filled yourself.

Reconciling the list is only half of reading it, though. The entries on that panel do not behave alike — some of them will vanish the moment you finish with whatever they belong to, and some will still be sitting there when the tank runs dry.

Only Cold Storage Is Charged for Existing — Everything Else Is Metered

The scan does not treat everything it finds the same way, and the difference between the two treatments is not a design decision anybody wrote a patch note about. It is visible in the shape of the code, and once you have seen it you cannot unsee it on the panel.

Walking its circle, the generator runs down a chain of type checks — is this object a television, a radio, a washing machine, a stove, a light switch, a car battery charger — and almost every one of those checks has a second condition bolted onto it. IsoTelevision && getDeviceData().getIsTurnedOn(). IsoStove && Activated(). IsoClothingWasher && isActivated(). IsoLightSwitch && activated. A television sitting three tiles from the generator with the screen dark satisfies the first half of its test and fails the second, so it never gets added to the tally and never appears on the panel at all. It is not being charged a reduced rate for standing there. It is not on the bill.

Then there is the branch for cold storage, and it asks a completely different question. It does not ask what the object is, and it does not ask whether anyone has switched it on. It asks whether the object declares a container: getContainerByType("fridge") and getContainerByType("freezer"). Both present, and the tile is charged 0.013 L/h. Either one on its own, 0.008. There is no second condition in either branch — no switch, no door state, no check for whether there is a single item inside.

Say that in plain language before the table arrives, because it is the whole finding: a fridge in Project Zomboid has no off switch. There is no power option in its context menu, the game does not model its door as anything the generator can see, and an empty fridge is billed exactly like a full one. Once it is inside the circle and the generator is running, you are paying for it every hour that both of those things stay true. There are exactly two ways to stop paying — move it out of the circle, or switch the generator off — and neither of them is a thing you do casually.

Here is the complete ledger. The middle column is the one carrying the argument.

The right-hand column is what your panel shows and what actually leaves the tank; the constant beside it is the underlying figure in the code, kept here because it becomes useful later. Four rows say always. Every other row in the game says only while.

Three of those four "always" rows are the same object class described twice over, plus the generator charging itself. The fourth is a genuine exception, and it needs stating rather than glossing, because otherwise the rule is a sentence you could disprove. A fuel pump is charged 0.003 per tile with no activation flag either — the test is getPipedFuelAmount() > 0, meaning a pump that still has gasoline in it. That is a forecourt, not a kitchen. Unless you have hauled a generator to a gas station, there will not be one inside your circle. So the rule, stated so it survives contact with the game: inside a base, cold storage is the only thing billed for existing.

And while we are on the forecourt — the arithmetic there is worth ten seconds. A generator standing at a gas station with nothing connected but one two-tile pump runs at 0.008 L/h: two tiles at 0.003, plus the machine's own 0.002. That is a fifth of a litre a day, 1,250 in-game hours, 52 days on a single can, to keep a pump alive that holds gasoline by the thousand litres. Powering a pump is not a fuel decision either; it is the most net-positive thing a generator can do. Whether the pumps near you still have anything in them, and whether it is worth the drive, is a question about gas stations and pump volumes, and it is another guide's.

The floor, and the whole floor

So here is the arithmetic the reader actually came for. Every total below includes the generator's own 0.002, and multi-tile appliances are counted per tile as always.

A generator connected to an entirely empty circle would take 208 in-game days to drink one gas can. Put a chest freezer in front of it and that collapses to 41.7. An industrial fridge, 27.8. The fourth row is the one to memorise, because it is what an ordinary functioning base actually looks like — one fridge, one freezer — and it comes to 0.023 L/h, or 0.552 litres a day, or 18.1 in-game days per can.

Now go back and look at what is in that table. A freezer. A fridge. A fridge and a freezer. Another fridge. Not one line of it is an appliance anybody switched on. That is not a base running at idle with the interesting things left out — that is the base, in full, with every metered object in the game sitting at zero. It is the floor, and it is the whole floor.

Everything else is smaller than you think

Lights are the clearest case, because people worry about them and the worry is misplaced. A light switch costs 0.0002 L/h while it is on — six lamps burning across the house come to 0.0012, which is a little over 5% of a fridge-and-freezer base. You could run a lamp in every room you own and it would not move the day count. Lighting a base is not a fuel decision; it is a decision about whether you want to be visible at night.

Three more entries exist in the code that the published rate tables skip entirely, and they are worth knowing about even though two of them barely matter:

• A radio is 0.001 L/h, and only while it is switched on and running off the grid rather than its own batteries. A battery radio inside the circle is not on your bill at all.
• A car battery charger is 0.005 L/h while switched on. Note that it only became a consumer at all in 42.13.0 — "Fixed IsoCarBatteryCharger, it now consumes power from generators" — so if you remember charging batteries for free, you were right at the time.
• A stacked washer-dryer carries a constant of 0.9 raw, 0.09 on the panel, per running half. That is ten times a standalone washer's, and a single running half would cost nearly four times what an entire fridge-and-freezer base costs at rest. Treat that one with suspicion rather than planning: the constant is unmistakably in the code, but no stacked washer-dryer tile appears in the Build 42 appliance list, and it is not worth building a laundry plan around an object nobody can confirm exists.

The cookers get their own section, because there is more to say about them than a rate. For now the rate is all you need: an oven, a stove and a microwave are all charged 0.009 L/h per tile, and only while activated. Switched off, which is what they are for the overwhelming majority of any day, they contribute exactly nothing.

What to do with this

Budget your gasoline against cold storage and treat everything else as free at rest, because at rest is what everything else genuinely is. The bill is not five appliances with five prices. It is a permanent charge, set entirely by how many fridge and freezer tiles are standing inside the circle, plus a set of things that cost you only in the minutes you are actually using them.

Which quietly answers the question most people arrive with. Can I afford a television? Yes, and it is not close. A television is 0.003 L/h — leaving it running around the clock, never once switching it off, costs about two days out of the eighteen. Watch it the way a person watches television and the cost rounds to nothing. The same goes for the radio, the lamps and the charger. None of them is the reason your tank is emptying.

The question that decides your runtime is the boring one: how many cold-storage tiles are inside the circle, and what kind. Every one of them is a permanent subscription you signed the moment it came to rest within twenty tiles of the generator, and it renews hourly whether you open it or not.

Which makes it the only fuel decision in the base worth thinking about at all — and the tiles you can choose between are nowhere near as interchangeable as their labels suggest.

An Industrial Fridge and a Mini Fridge Cost the Same 0.013 L/h

The scan has never seen a sprite and does not know what any of these things are called. When it stops on a tile it asks two questions and only two: does this object declare a fridge container, and does it declare a freezer one. Both, and that tile is 0.013 L/h. Either one alone, 0.008. Then it steps to the next tile and asks again — which is the second question, the one hiding in plain sight. Not what is this appliance, but how many tiles is it standing on.

Neither question has anything to do with how much the thing holds. That is the whole of it, and it is why the heading is not a typo.

Look at what a Mini Fridge actually declares: a fridge container of capacity 20, and a freezer capacity of 5. Two boxes ticked, so the branch resolves to both, so the tile is billed at 0.013 L/h. Now look at an Industrial Fridge: a fridge container of 40, a freezer of 20. The same two boxes, the same single tile, the same 0.013 L/h. The test is for presence, not for size — there is no arithmetic anywhere in that branch that scales the charge to the capacity behind it. The Mini Fridge's five-unit freezer nook costs exactly what the Industrial's twenty-unit compartment costs, because the code only ever wanted to know whether one existed.

So the two appliances are billed identically, occupy identically one tile, and hold 25 against 60. That is 2.4 times the storage for the same fuel and the same footprint, and there is no downside hiding in the trade: an Industrial Fridge needs no skill and no tool to pick up, and at encumbrance 40 it is the same carry as the Large Fridge and the Popsicle Freezer. If a Mini Fridge is what your house came with, an Industrial one is worth a trip to a restaurant or a shop before you commit generator time to it, because once it is inside the circle you are paying the full rate for a quarter of the storage, hour after hour, and nothing about that improves later.

What each tile is actually worth

Divide storage capacity by the rate and the whole cold-storage aisle sorts itself. These are appliance rates only, with the generator's own 0.002 left out, because the baseline is charged whether you own a fridge or not. And read the ranking for what it is — capacity in Project Zomboid is a weight budget, not a slot count, and the fridge-to-freezer split differs by unit, so this tells you which tiles are efficient, not which tiles substitute for each other:

The Industrial Fridge is the best tile in the game by this measure and it is not close — it buys 2.4 times as much storage per litre as the Mini Fridge and 1.7 times as much as the Large one. Notice also that the appliance sitting at the bottom of that table and the appliance sitting at the top are charged the same rate, and that the two entries in the middle score identically for a reason worth stating: a Popsicle Freezer is, as far as the bill is concerned, two Chest Freezers welded together. Each of its tiles declares a freezer container of 30 and is charged 0.008, which is a Chest Freezer exactly. Its per-litre value is therefore 3,750 whether or not you accept its total of 60 — and you should hold that total loosely, because it is inferred from two per-tile dumps plus an infobox from a Build 41-era wiki page. Treat it as two 30-capacity halves you cannot separate, which is what the game actually gives you.

The Large Fridge trap

Now the swap that costs people days without their noticing, and it was sitting in the standing-cost table in the last section the whole time. Two of those rows are the same two tiles.

A Large Fridge is a two-tile appliance, and both of its tiles declare a fridge and a freezer, so it is charged twice: 0.026 L/h, plus the baseline, is 0.028 L/h. Ten litres divided by that is 357 hours — 14.9 in-game days per can — and what you get for it is 70 capacity.

Put the arithmetic the other way round and it is stark. The Large Fridge's second tile costs 0.013 L/h, which is precisely what an entire Industrial Fridge costs, and it buys ten more capacity than an Industrial Fridge would have given you on its own. That second tile is the worst-value square metre of cold storage in the game.

Spend the same two tiles deliberately instead. An Industrial Fridge plus a Chest Freezer is 0.013 + 0.008 = 0.021 L/h, 0.023 with the baseline, which is 435 hours or 18.1 in-game days per can — and 90 capacity. Same two tiles, and it wins on both axes at once: +28.6% storage and +21.7% runtime, better than three extra days out of every gas can.

It is a better shape as well, though this is where the weight-budget caveat earns its place, because 90 mixed is not simply 70 with a bonus. The Large Fridge splits 50 fridge to 20 freezer. The pair splits 40 to 50. You give up ten units of chilled space and gain thirty units of genuine freezer, which is the compartment you were paying the extra 0.005 L/h per tile for in the first place. If your plan leans on frozen goods rather than merely cold ones, that is not a side effect of the swap, it is the point of it.

Two footnotes on acquiring the winning pair. The Chest Freezer is the only unit here that cannot simply be lifted — it needs a pick-up level of 3, where the Industrial, Large and Mini Fridges and the Popsicle Freezer need no skill and no tool at all. And if you have been running an unstable build, note that 42.18.0 fixed "non-standard fridges failing to apply the refrigeration modifier to chilled food." Which tiles counted as non-standard is not stated anywhere, so this is one changelog line and no more — but if you kept food cold in something unusual before that patch and it spoiled anyway, that is the likeliest reason, and it is fixed now.

What to actually do with a cold-storage find

Choose by capacity per litre, and count tiles before you count appliances. The label on the sprite is the least informative thing about it: "Large" is the trap, "Mini" is billed like the best unit in the game while holding a quarter of what it holds, and the two tiles you have to spend are the real currency. An Industrial Fridge and a Chest Freezer inside the circle is the base to aim at — 90 capacity, 0.023 L/h all in, eighteen days a can — and the Large Fridge that looks like the upgrade is the one to leave in the kitchen you found it in.

Which settles what the standing charge costs. It does not yet say what it buys, or how much of it survives the moment the tank hits zero.

What the Standing Charge Buys: Five Times the Shelf Life, and a 90-Minute Cliff

What it buys is a single number: 0.2. That is the temperature a fridge or freezer container reports while it has power, against the 1.0 of ambient air — and it is also, not coincidentally, the multiplier the game applies to how fast the food inside it ages. Every hour a fridge spends inside a running generator's circle, its contents age at a fifth of the rate they would on a kitchen shelf. A fifth of the rate is five times the shelf life, and that is the entire return on the only permanent line of your bill.

It is worth being precise about the two conditions, because between them they explain why the charge is unavoidable and why it is worth paying. When the game ages a perishable it looks at the outermost container the item is sitting in, and it applies the 0.2 only if two things are true at once: the container is a fridge or freezer type, and its square's grid actually has electricity. Miss either and the food ages at the full rate. An Industrial Fridge with no power behind it is not a slow fridge. It is a cupboard — a cupboard you have hauled up a staircase, and one that will still be charged 0.013 L/h the instant a generator starts inside twenty tiles of it. The appliance contributes nothing. The electricity is the whole product.

You can see it working. Refrigerated items carry a blue overlay in the container, and the effect on a real item is exactly what the arithmetic says: PZwiki's worked example is a fish fillet, which goes stale in 2 days on a shelf and 10 days in a powered fridge. Nothing about the fillet changed. You bought it eight extra days for a fifth of a litre a day.

Frozen is not colder, it is a different category

Freezing is where the model stops being a multiplier at all. A refrigerated item ages at 0.2 of normal; a frozen item has its age increase multiplied by 0.0. Not 0.05, not a very small fraction — zero. While the item is fully frozen, the clock does not advance. That same fish fillet does not last a longer number of days in a freezer; it stops having a number of days, for as long as it never thaws in between.

That difference is why the freezer half of the bill is a different purchase from the fridge half rather than a premium version of it. And it is also why the distinction between the two tile types matters more than the labels suggest: only a container of type freezer freezes anything. A Chest Freezer and a Popsicle Freezer are freezer-only. A Mini, Industrial or Large Fridge carries both containers — a fridge compartment and a freezer compartment — which is precisely why the code charges those tiles 0.013 instead of 0.008. The extra 0.005 L/h per tile is the freezer compartment, itemised and unavoidable, and it is the only part of the whole ledger that stops decay rather than slowing it. Everything the fridge side does, it does at 0.2. Everything the freezer side does, it does at zero.

One caveat on the five, because it is a default rather than a constant. The multiplier is a sandbox option, FridgeFactor, and it maps to 0.4, 0.3, 0.2 by default, 0.1, 0.03 or 0.0 — which is refrigeration worth ×2.5, ×3.3, ×5, ×10, ×33, or an unlimited shelf life in any powered fridge at all. If someone tuned that on your server, the ten-day fillet moves with it. The 0.0 applied to frozen food is not part of that scale and does not move.

The ninety-minute cliff

Here is the asymmetry, and it is the sharpest practical number in this guide.

Freezing takes four in-game hours. Thawing takes ninety in-game minutes.

The two clocks are the same clock run in opposite directions at different speeds. Freezing only happens in a freezer-type container that is powered, and it fills a 0–100 meter at 25 points an hour — four hours from unfrozen to frozen. Thawing runs whenever that meter is above zero and the item is not in a powered freezer, and it drains at nearly 67 points an hour. Which means, put as a planning rule: every hour your generator spends dry costs you two hours and forty minutes of power to undo.

Two modifiers sit on the thaw side, and only one of them is ever good news. An item in a powered fridge compartment thaws at half speed — three hours instead of ninety minutes — so if you have frozen goods you want to hold in a soft state, the fridge side of the same appliance is genuinely the place to put them. Note the word powered, though, because it disqualifies the case you actually care about: when the tank hits zero, the fridge compartment is unpowered too, and the doubling does not apply. The other modifier runs the wrong way entirely — anywhere warmer than ambient divides the thaw time by six, and the item is gone in fifteen minutes.

So run the fillet through a dry tank. It is frozen, which cost four hours of freezer power to achieve. The generator runs out at, say, three in the morning. By 04:30 the meter has emptied, the item is fully thawed, and it is ageing at the full rate again — not the refrigerated fifth, the full rate, because the fridge factor needs electricity too and there is none. You walk back in with a can at midday. Refuelling restores the 0.2 immediately, but the frozen state is a four-hour rebuild from scratch. Ninety minutes to lose it, four hours to get it back, and every hour in between charged at shelf rate.

A freezer is not a buffer against running out of gasoline. It fails faster than the trip to fetch more.

It is worth contrasting that with the one grace period the game does hand out, because it makes the absence of a second one obvious. On the day the mains die — that specific day — the game lerps the temperature inside every fridge and freezer in the world from 0.2 to 1.0 between 07:00 and 13:00. The world's cold storage does not snap off; it fails over a morning, and there is time to notice. A generator gives you no such ramp. Any day that is not the shutoff day, an unpowered container reports ambient the moment it loses power, and the ninety-minute thaw clock is the entire warning you get.

And do not expect the food to tell you. Until 42.19.0 the label actively lied in the other direction — items showed as frozen while they were still inside the four-hour freezing window — so a habit of glancing at item names for reassurance was never reliable, and it is a poor instrument even now that the name is honest. (The same run of fixes tidied up an adjacent one: 42.12.0 stopped animal corpses ignoring the time-slowing effect of fridges and freezers, so a carcass in cold storage is finally treated like everything else in it.)

What to actually watch

Refuel on the Fuel percentage on the Generator Info panel, and never on the state of the food. The food is a lagging indicator with a ninety-minute fuse; the fuel reading is the same information four hundred hours early. You already have the runtime — the tank divided by the panel's total — so treat that figure as a calendar entry rather than a fact about the generator.

That also settles how to plan a trip. If a run will keep you away longer than the tank covers, the freezer is not going to hold the difference, and no amount of pre-freezing changes that, because the four hours you spent building the frozen state buy you exactly ninety minutes of it once the fuel is gone. Plan the trip against the fuel, not the food against the trip. If the arithmetic genuinely does not work — you are going far, and the can will not stretch — the answer is not a colder freezer. It is keeping food without cold at all, which is preserved jars, plant drying racks and a winter pantry, and it is a different discipline and another guide's.

That is the permanent half of the bill accounted for: what it costs, which tiles to spend it on, and what it buys. The oven and the microwave are charged on a completely different basis — and the difference between running them well and running them carelessly is worth more days than anything you have read so far.

The Stove and the Microwave Cost Nothing Until You Press Start

You already have the rate. What the rate does not tell you is that there is only one of it. Walking its circle, the generator runs a chain of type checks looking for things it recognises, and cooking appliances get exactly one line in that chain: IsoStove && Activated() → 0.09 raw, 0.009 L/h on the panel, per tile. Not one line for ovens and another for microwaves. One line, one class, one price.

That is because a microwave is an IsoStove. It is the same object type as the oven in the same kitchen, with a Microwave property flipped on to change how it behaves when you use it — a maximum temperature of 100 instead of 200, a container that holds five items, a bell that rings sooner. None of that reaches the generator. The scan asks whether the object is an IsoStove and whether it is activated, and a microwave answers yes to both in exactly the way an oven does.

This matters because the published rate table has no microwave row at all, and a reader who takes that table as complete will conclude a microwave is free. It is not free; it is undocumented. The code has one branch, and it is the only place either appliance can be charged from. There is independent confirmation in the patch notes, too: 42.19.0 lists "Fixed generator fuel consumption not being updated when microwaves automatically shut off." That sentence only makes sense if a microwave is a load, and if that load is tied to its on/off state — which is precisely what the branch says.

The per-tile rule from the panel still applies, so count before you price. Most ovens are one tile and cost 0.009 L/h while lit. A Large Modern Oven is two tiles, so it is two objects and it is charged twice, at 0.018 L/h. Every microwave is a single table-top tile, so a microwave is always 0.009 and never more.

Cooking is not the expense

Now put a real number on an hour of use, because the number is smaller than almost anyone guesses.

An hour of oven costs 0.009 litres. The tank holds 10, so that hour is 0.09% of a full can — nine hundredths of one percent. Turn it around: 10 ÷ 0.009 = 1,111 in-game hours of oven on a single can, if the oven were the only thing on the bill. That is forty-six in-game days of continuous cooking. For scale against the charge you cannot switch off, an hour of oven costs less than half of what an Industrial Fridge and a Chest Freezer spend in that same hour just sitting there.

So price a realistic cooking habit against the base you already have. The fridge-and-freezer base spends 0.552 litres a day. Cook an hour on the oven and an hour in the microwave, every single day without exception:

• Two appliance-hours a day at 0.009 each = 0.018 L/day added
• 0.552 + 0.018 = 0.570 L/day
• 10 ÷ 0.570 = 17.54 days per can

Cooking every day of your life, on both appliances, costs you about fourteen hours of runtime out of eighteen days. Half an in-game day. That is the entire bill for cooking, and it is small enough that there is no version of this decision worth agonising over. Cook. Cook twice. The oven is the fastest heat source in the game and you are not paying for it in any way you will notice.

The forgotten oven, though, is real money

Here is the same base with one habit changed. Leave the oven and the microwave switched on — not cooking, just activated, the way an appliance ends up when you walk away from it — and both are charged every hour the generator runs:

In hours rather than days, that is 244 against 434. Switching two appliances off is worth just under eight days out of every gas can — and nothing else in this guide, not the fridge you pick, not the lights, not the television, comes close to that as a single lever. Two appliances that cost nothing at rest will nearly halve your runtime if you never turn them off.

And the two of them are not equally likely to do it to you, which is the part worth internalising. IsoStove.update() runs a check every tick that reads, in substance: if this object is activated, is a microwave, and its stop time has passed, deactivate it. A microwave that finishes its cycle switches itself off. A stove that finishes its cycle does not — the same expiry plays the StoveTimerExpired sound, clears the timer, and leaves the appliance activated. The bell rings, the oven stays lit, and the 0.009 keeps coming out of the tank until you go back and turn the dial yourself.

Price that one appliance on its own. A forgotten oven takes the base from 0.023 to 0.032 L/h — 312.5 hours, 13.0 days instead of 18.1. One dial you did not turn costs five days a can. Put it in cooking terms and it is worse than it sounds: leaving an oven lit for a single day burns twenty-four appliance-hours, which is what cooking an hour a day for over three weeks would have cost you.

The microwave is structurally hard to make that mistake with. It stops itself on the timer; it turns off when its door is opened; and since 42.6.0 and 42.7.0 a microwave switched on with no time set defaults to one minute rather than the old hour, so even the careless case expires in sixty seconds. The oven has none of that. It is the one appliance in a Project Zomboid base that will quietly bill you forever because you were distracted.

Two habits fix it permanently. The first is checking the panel rather than the kitchen: flipping a hob calls IsoGenerator.updateGenerator() on that square, so the load recalculates the instant you switch, not at the next hourly tick. Turn the oven off and the total on Generator Info drops by exactly 0.009 while you are looking at it. If it does not drop, you turned off something else.

The second is checking after a power cut, because losing power does not leave things where you put them. The stove code deactivates any activated appliance whose container is unpowered — if (Activated() && (container == null || !container.isPowered())) setActivated(false). So when the tank runs dry, or you move the generator out of range, the oven and the microwave both switch off on their own. That sounds like the game doing you a favour, and in one narrow sense it is: a dry tank is the only thing that ever cleans up after a forgotten oven. But neither of them comes back on when power returns. You walk in with a fresh can, the fridges resume, the lights resume, and the pot you left on the hob at three in the morning is sitting cold in a kitchen that has power again. Refuelling restores the circuit, not your appliances. Switch the hob back on by hand, and check it before you start counting on it.

The microwave is the appliance that travels

There is one more consequence of the two appliances sharing a rate, and it only shows up when the circle does not reach your kitchen.

If the generator has to stand where it stands — outdoors, away from the building, at the far end of the yard — and the kitchen falls outside the twenty tiles, you have two options: move the generator, or move a cooker. The cooker is almost always the easier move, and only one of the two cookers is genuinely portable.

A microwave is encumbrance 10, sits on a table-top, and needs no skill and no tool to pick up. You can lift one out of any kitchen in Knox County and set it down on a counter next to the generator in the same trip. An oven is encumbrance 20 to 25 and needs Electrical plus a screwdriver to detach — a real job with a skill requirement in front of it — and an antique Old Stove is 40 and will not fit in the same plan at all.

So the trade is clean, and it is not the one people expect. The oven is the better cooker: maximum temperature 200 against the microwave's 100, and the wiki rates it the hottest heat source in the game, which means faster cooking. The microwave is the better tenant: identical price on the bill, a fifth of the weight, no tool, no skill, and a slot on a shelf. When you cannot bring the circle to the food, bring a microwave to the circle — it costs the same 0.009 while running and nothing at all in between.

A few things worth knowing about running either one, since neither changes what you pay:

• Both have an alarm, and the microwave's is strong enough that the wiki calls it "very unlikely food will burn." The oven's is real but weaker.
• Both have a lowest setting too cool to cook, which makes either one a safe defroster — genuinely useful if you have been building frozen stock and want it usable without gambling on the fifteen-minute warm-room thaw.
• Both keep cooking after you switch off, because high temperatures cool slowly. Switching a hob off saves fuel immediately; it does not necessarily save dinner.
• Never put metal in a microwave. It breaks the appliance and starts a fire with an energy value of 10,000 — an order of magnitude above what a failing generator itself produces. 42.14.0 fixed a related case of microwaves catching fire on metal objects, but the mechanic is still there and it is not a small fire.
• A microwave holds five items, and some foods raise Unhappiness and Boredom when microwaved rather than cooked properly. That is a mood cost, not a fuel one.

Cook freely, then. The only expensive thing either appliance can do to you is stay switched on while you are somewhere else, and only one of them is capable of it. Turn the oven off when the bell rings, check both after any power cut, and if the generator cannot reach the kitchen, carry the microwave to the generator rather than the other way round.

That prices the fridge, the freezer, the stove and the microwave. The fifth thing every survivor starts planning the day the utilities die is water — and it is the one subject that never appears on the panel at all, which makes budgeting gasoline for it a genuine and fairly common mistake.

Your Water Plan Does Not Need the Generator at All

Go back to the chain of type checks the generator runs as it walks its circle. Television. Radio. Washing machine, dryer, combo unit. Stove. Fridge container, freezer container. Light switch. Car battery charger. Fuel pump with something still in it. That is the chain, and it is the whole chain. There is no branch for a sink. There is no branch for a bathtub, a toilet, a well, a rain collector barrel or a water dispenser, and the reason is not that the developers forgot to add one. It is that there would be nothing for such a branch to do.

A Knob Creek Gas & Electric van abandoned beside an open manhole. Nobody is coming back for either grid — and a generator only ever answers one of them.

Water in this game is not an electrical product. No source of it requires power, none of it is improved by power, and none of it appears on the Generator Info panel in any form, because there is no state a generator could put a water fixture into that it is not already in. PZwiki's plumbing documentation says it in one line, about the one fixture people most expect to be an exception: plumbed sinks work without electricity. So does everything else that holds water.

Which makes the honest budget figure zero. Not "less than you'd think", not "a small amount" — zero litres of gasoline, permanently, for the entire water half of your survival plan. If you have been holding a can back against the water problem, that can is doing nothing but taking up encumbrance.

The reason this catches people is that both utilities die in the same fortnight and it feels like one event. It isn't. Power and water are two separate grids with two separate shutoff dates, rolled separately, and the water shutoff has nothing to do with the electrical one — it can land first, it can land weeks later, and one of them arriving tells you nothing about the other. A generator restores exactly one of the two, locally, inside twenty tiles. There is no setting, no appliance and no skill level that makes it restore the other. When your tap stops running, it did not stop because the power went out. It stopped because the water went out, and no amount of gasoline addresses that.

Everything that gives you water gives it to you with no power at all

The full list of things that keep working, before and after the shutoff, with a dead grid and no generator anywhere on the map: taps, toilets, bathtubs, showers, wells, rain collector barrels, water dispensers, and any sink you have plumbed to a reservoir. That is not a list of things that degrade gracefully without power. It is a list of things to which power was never an input.

The residual figures make the point concrete, because they are fixed quantities that a generator neither adds to nor subtracts from. After the mains stop, every sink variant still holds 20 units, a Low or Fancy Toilet 20, a Large Deluxe Bath 100, and a Water Dispenser 250 — twenty-five bottles' worth sitting in a container you can pick up and carry without tools. Run a generator beside any of them and every one of those numbers stays exactly where it was. Switch it off and they stay there too. The relationship is not weak; it is absent in both directions.

The two intersections, and they really are the entire list

There are exactly two places in Build 42 where electricity and water touch each other, and both of them are optional, metered conveniences rather than water sources.

A washing machine. This is the one genuine intersection, and it is genuine because it needs both halves at once: a water connection — mains, or plumbed to a reservoir sitting one floor above it and within a three-by-three — and local power inside the generator's circle. Miss either and the machine does nothing. Satisfy both and it costs 0.009 L/h, only while a cycle is actually running, which is the same rate as an hour of oven and the same activation gate as everything else on the metered half of the ledger. It washes clothes. It does not produce a drop of drinking water. (Plumbing a fixture to a rain collector barrel belongs to the plumbing guide, and the stacked washer-dryer's alarming constant was dealt with back in the load table.)

Boiling. This one is indirect but real. Tainted water is cleared when the item's heat rises past 1.6 — and 1.6 is a threshold that sits just above ambient, which is why nothing clears it by sitting still. A powered fridge container reports 0.2. Ambient air reports 1.0. Neither is going anywhere near it. An active oven climbs toward 200 and a microwave sits at 100, so either one overshoots the threshold by a factor of sixty or more, at 0.009 L/h while it runs and nothing at all in between. If a cooker is already inside your circle, purifying water on it costs you nothing you were not already paying. The non-electric routes to the same result — a campfire, a well, Water Purification Tablets — and the business of reading the tainted flag on a container belong to the heat-sources and water guides — this is only the half of it that touches the fuel bill. Note the confidence, too: that 1.6 threshold is read out of the Build 42 code, not measured in a running game.

That is the closed list. A washing machine you have also plumbed, and boiling on an electric hob. Everything else — every tap, every toilet, every bathtub, every well, every rain collector barrel, every water dispenser, every plumbed sink — runs on nothing.

It is worth saying what that negative rests on, because a confident zero deserves to be checkable rather than trusted. Three of the wiki pages that describe water fixtures still carry Build 41-era banners, so they are not proof on their own. What backs them up is the code and the changelogs: no power-gated water class appears anywhere in the decompiled source, and no Build 42 patch note introduces one — the only water-and-electricity line in the whole run is 42.13.0 fixing a water tower that was playing electrical sound effects because of the pylon tiles underneath it, which is a cosmetic bug and not a mechanic. Treat this as high confidence rather than absolute, and know exactly which part is the weak one: if a powered water fixture existed, it would need a branch in that scan chain, and there isn't one.

So delete water from the fuel budget entirely, and delete it from the generator's job description while you are at it. If your water plan is not working after the shutoff, more gasoline is never the fix — the fix is a rain collector barrel, a well, a plumbed sink, or Water Purification Tablets, and not one of those cares whether your generator is running. The only thing worth carrying forward from this section is the small one: if you already have an oven or a microwave inside the circle for cooking, you also already have a purifier, and it is charged at the same 0.009 you were paying for dinner.

Which prices all five of the things a survivor starts worrying about the day the utilities die, and the total is faintly ridiculous: about half a litre a day, eighteen days on one can, with a fifth of the list costing nothing at all. And yet you will find no shortage of players who will tell you, in detail, that their generator drank a full can overnight — and a whole generation of Build 41 veterans who will tell you two freezers is the limit. Neither is making it up. Both are describing a fault that has since been fixed, and neither fault had anything to do with what was plugged in.

If Your Tank Empties in a Day, It Is One of Two Old Bugs

Take both reports seriously, because both of them are accurate. The players who watched a full can vanish between one morning and the next were reading their fuel gauge correctly — their saves really were burning it that fast. And the Build 41 veterans who will tell you flatly never to run more than two freezers were right when they learned it; one of them measured the effect five times over, carefully, and the numbers they got are exact. Neither group is misremembering. They are describing two different faults in two different builds, and neither fault has anything to do with what is plugged in.

Bug one: your save is still running the old multiplier

Build 42.12 did two things to the fuel model on the same day. It fixed the way the generator adds up its load, and it rescaled everything around that fix — the tank, and the sandbox multiplier standing between the constants and the tank. GeneratorFuelConsumption had defaulted to 1 for the whole of Build 41. The patch dropped the default to 0.1 "to reflect fixes in consumption", and 0.1 is what every figure in this guide assumes.

The trouble is what happens to a world that already exists. Sandbox values are stored per save, so a game created before 42.12 — or a custom preset you built once and have been reusing ever since — carries the old 1.0 forward into the new ten-litre tank. Everything else about the model updates. That one number does not. The patch notes said so on the day, in a header warning: existing saves will likely experience increased fuel consumption, and the setting can be changed in debug mode. Players reported worlds created before the patch staying broken after they updated, which is exactly what a stored value does.

The result is not a slightly thirstier generator. It is a bill ten times the published one, arriving on saves whose owners have no reason to suspect the sandbox.

One player on 42.12 posted enough detail to check by hand, and it lands cleanly. Inside their circle: a fridge-and-freezer unit, one popsicle freezer, three gas pumps and nine light switches. In code constants, counted per tile the way the scan counts them:

Two of those five rows are shakier than the rest, and it is better to say so at the table than after it. The nine light switches were very likely not being charged at all on 42.12 — that is precisely what 42.20.0 later fixed. The three gas pumps are the bigger question at 0.18, better than a third of the whole total, on a save predating 42.19.0's "Fixed gas station pumps not properly recognizing available electricity". Together they are 0.198 of the 0.508. Strip both and the raw prediction falls to 0.31, which is the number to argue with if you want to.

At the intended multiplier of 0.1, that base costs 0.0508 L/h. They refuelled at 06:00 and were down to 20% by 20:00 — fourteen hours, eight litres gone, an average of 0.571 L/h. At 0.1 the tank should have lost 0.7 litres in that window. It lost eight.

Multiply the same raw total by 1.0 instead and the prediction is 0.508 against a measured 0.571 — about 12% out, which is what you get from a fuel percentage eyeballed to the nearest ten and a window rounded to the hour. Take the stripped-down 0.31 instead and the measurement overshoots rather than undershoots. Either way it sits in the neighbourhood of 1.0 and nowhere near 0.1.

Run both out to a runtime and the whole thing snaps into focus. Ten litres divided by 0.508 is under twenty hours a can. Divided by 0.0508 it is 197 hours, a little over eight days. Which is almost word for word what a user of the community fix mod reported after correcting the setting on an existing save: it took them "from 1 day of power to almost 9."

The thirty-second check

You do not need any of that arithmetic to find out whether it is happening to you, because the generator prints the multiplier on the panel without meaning to. The bottom line — the machine billing itself — is the raw baseline constant of 0.02 with the multiplier already applied. At the Build 42 default it reads 0.002 L/h. If your panel reads 0.02 on that line, your save is running at 1.0, and every other entry on the screen is ten times too high with it.

The long form is the same test done properly: add up the code constants from the ledger a few sections back for everything you have inside the circle, multiply by 0.1, and compare to the panel's total. A rough tenfold gap is the migration. It is not your appliances, and no amount of unplugging things will close it.

The fix is one setting. Debug mode → Sandbox Settings → Meta → Generator Fuel Consumption → 0.1, applied to the world you are already in. It is worth knowing why the confusion keeps regenerating, too: PZwiki's Custom Sandbox page still lists the default as 1, because that page's version banner is 41.78.19 and it was never revised after 42.12. A reader checking the wiki to see whether their setting looks wrong is told it looks right.

One dissenting note, recorded rather than endorsed. A single commenter reported fuel still draining after they set the multiplier to 0.1 and then to 0.0. The report gives no build number and no mod list, nobody has reproduced it, and the code multiplies straight through — a 0.0 multiplier subtracts zero, arithmetically. Treat it as unexplained rather than as a known issue, and if your own numbers refuse to respond to the setting, look for a mod before you look for a bug.

Bug two: Build 41 charged a penalty for owning two of anything

The second explanation is older, and it was not a misconfiguration. It was the game.

In Build 41, identical appliances did not add up — they compounded. The routine that added an object to the load list counted how many objects of that display name it had already seen, and then added that many units of cost instead of one. The second object added the same as the first. The third added two units. The fourth added three, the fifth four. Total for n identical objects: (1 + n(n−1)/2) × v — the sequence 1v, 2v, 4v, 7v, 11v, 16v.

A player measured it in 2023 by putting popsicle freezers down one at a time and reading the panel after each, which is genuinely good amateur science, and their five points reproduce the formula exactly. Each popsicle freezer is two tiles, so it is two objects at 0.08, on top of the 0.02 baseline:

Five for five, to the second decimal, against a formula the measurer had never seen. Their summary was that five freezers "guzzles up as much fuel as normally 23 freezers would" — and that checks out too: strip the baseline off 3.70 and divide by the 0.16 a single freezer ought to cost, and you get exactly 23. They were not exaggerating for effect. They had done the division.

Those are Build 41 rates against Build 41's fuel pool, and they do not convert into days. The pool was clamped at 100 units rather than 10 litres, so the two builds cannot be put on the same clock. Compare them as rates or not at all.

Build 42 made it linear

The rewritten routine subtracts the old subtotal before re-adding the new one — powerConsumption × nbr out, powerConsumption × (nbr+1) in — so n identical objects now cost exactly n × v. This is what 42.12.0's terse "Fixed Generators consuming incorrect fuel" is referring to.

The same five popsicle freezers: ten tiles at 0.08 is 0.80, plus the 0.02 baseline, 0.82 raw — 0.082 L/h on the panel. Against Build 41's 3.70, that is a 4.51× reduction in rate, and because the tank and the constants were both rescaled by the same factor of ten, the ratio survives the change of units: 3.7% of the pool an hour then, 0.82% of the tank an hour now.

What that does to the veteran's rule is worth spelling out, because the rule costs storage. The marginal cost of a freezer is flat now. The third popsicle freezer costs 0.016 L/h, and so do the fourth and the fifth — the same as the first. In Build 41 the third one added 0.72 to the running total where a fair charge was 0.16, and the fifth added 1.36. That escalation is the entire substance of "never run more than two freezers", and it does not exist any more. Five popsicle freezers in Build 42 come to 0.082 L/h — 122 in-game hours, a little over five days on a can. That is a real cost, but it is the cost of ten tiles, priced as ten tiles, which is the only thing the old rule was ever protecting you from.

The 0.1 default was a rescale, not a discount

It is tempting to read the multiplier change as a tenfold buff to generators generally, and it is not one.

Here is the cancellation, stated as an equivalence check and nothing else. One Industrial Fridge, nothing else in range: raw 0.13 plus the 0.02 baseline is 0.15 in either build. Build 41 spent 0.15 an hour against a pool of 100 → 666.7 hours. Build 42 multiplies the same 0.15 by 0.1 to get 0.015 L/h against a tank of 10 → 666.7 hours. Identical to the decimal. That is not a claim about how long a Build 41 generator ran in practice — Build 41's pool is not litres, and the builds are not comparable on a clock — it is a demonstration that dividing the tank by ten and the rates by ten nets to nothing.

Which locates the real Build 42 improvement precisely: it is the duplicate fix, and it only appears once you own more than one of the same appliance. If your Build 41 base ran a single fridge, Build 42 changed nothing for you at all.

Two smaller reasons a stranger's numbers will not match yours

Lights were not actually being charged until the stable release. 42.20.0's notes carry the line "Fixed lights not properly consuming generator power" — so for the whole of the unstable run the per-switch rate was on the books and was not coming out of the tank. That is one changelog line: the effect it describes is unambiguous, the exact prior behaviour is not. The amounts involved are too small to move anybody's budget, and it is one of the two rows already discounted at the field arithmetic above — which still lands an order of magnitude away from 0.0508, the only comparison that was ever load-bearing.

The other reason is 42.19.0, which fixed three accounting faults in one patch:

• fuel consumption calculated incorrectly while the generator was outside a loaded chunk — that is, whenever you were not near it
• consumption not recalculated when a microwave shut itself off, so the load went on including an appliance that had stopped
• gas pumps not properly recognising available electricity

Read that list as a warning about second-hand numbers. Measurements taken on 42.13 through 42.18, especially on a base the player walked away from and came back to — which is how almost everyone measures fuel drain — are not reliable. A large share of the figures circulating in discussions were taken inside that window.

Where the numbers in this guide come from

Which raises the fair question about my own figures, so here is exactly what they rest on.

Every constant quoted here is read out of a decompile of Build 42.13.2 — the load branches and their activation gates, the multiplier, the freeze and thaw timings, the wear and failure rolls. I then read every changelog from 42.14.0 through 42.20.0 looking for a changed consumption constant, and there is not one. What those builds changed was when consumption is recalculated: unloaded chunks and microwave shutoff in 42.19.0, lights in 42.20.0. Not what anything costs. Independently of all that, PZwiki's consumption table — maintained by people working from the game rather than from that decompile, and carrying a page banner of 42.13.1 — reproduces all seven of its rows at exactly one tenth of the raw constants.

So take these as Build 42.20 behaviour, verified against 42.13.2 code plus every changelog in between. That is a strong position, it is not the same thing as having read 42.20's source, and you should know which of the two you are being handed.

Before you trust any generator number — mine, a forum post's, or your own — check the multiplier. It is one glance at the bottom line of the panel. If it reads 0.02 where it should read 0.002, you have your answer, and correcting the setting makes every figure in this guide true for your save in the same instant. And if your caution about duplicate appliances came from Build 41, retire it: cold storage is priced by the tile now, the second freezer costs what the first one did, and the storage you have been refusing yourself was free the whole time.

With the multiplier where it belongs, the arithmetic stops being contentious. Half a litre a day. Eighteen in-game days to a gas can. A fuel gauge that moves so slowly you will forget to look at it — which is fine, because it was never the gauge that was going to end this generator.

Condition, Not Fuel, Is the Clock

Go back to the panel this guide opened with. Two figures sat above the itemised list and only one of them has come up since. Fuel 89% is the one every section so far has been arithmetic about. Condition 98% is the one that decides how long you own the machine, and it is spent on a completely different basis — one that has nothing whatsoever to do with the list underneath it.

Here is the whole mechanic. Once per in-game hour that the generator is switched on, it makes a single roll: one chance in C that this hour damaged it. On a hit it loses Rand.Next(2) + 1 — one or two points, evenly split, so 1.5 on average. On a miss, which is most hours, nothing happens at all. There is no gradual meter and no accumulating strain; there is one coin toss an hour, and the coin is heavily weighted in your favour.

That C comes from the generator's item script, and it is the number the reference tables print as Durability: Premium Technologies 36, Lectro-Max 30, Old 25, ValuTech 24. Read those the wrong way round and you will pick the wrong generator, because Durability is not a pool of hit points that a bigger number makes deeper. It is the denominator of a chance. A Durability of 36 fails its roll one hour in thirty-six; a Durability of 24 fails one hour in twenty-four. Higher is better because higher is rarer.

Which makes the expected wear easy to put a number on. An average of 1.5 points on a one-in-C hour is 1.5 ÷ C points per running hour, and over a twenty-four-hour day, 36 ÷ C:

Those last two columns are the only place the four variants ever separate. Every one of them powers the identical 41-tile disc, prices every appliance identically, and holds the identical ten litres — so the entire difference between the best generator in the game and the worst is on this table. A Premium Technologies unit is worth half again as many running days as a ValuTech, and it is the quieter of the two on top of that. The spread is deliberate rather than incidental: 42.1.0 made the Old unit significantly louder and the ValuTech louder by less, noting in the same breath that both already degrade faster while the Premium degrades slower, and 42.4.0 then trimmed some of the sound radius and volume back off the Old and cheap units. What you are choosing between is a running cost, not a capability.

Two things about that table before you plan anything off it.

The first is that every figure in it is days of running, not days on the calendar. The roll only happens inside the block that runs when the generator is activated — a unit sitting switched off ages not at all, indefinitely, regardless of how long it sits. Run a Lectro-Max eight hours a day and its sixty-seven days of running are two hundred days of your survivor's life.

The second is that they are ceilings, not schedules, because they all start from a pristine 100 and you will almost never be handed one. A generator you found in a shed, or hauled back from the Louisville border camp, has whatever condition it spawned with, and that is not full. The panel in the first section is the demonstration: it reads 98%, on a wiki's own illustrative screenshot, and 98 is not 100. Read your own Condition figure before you count days off this table, and subtract from where you actually are.

The fuel clock against the condition clock

Now put the two gauges side by side on the same base, because that comparison is what this whole article has been walking toward.

An Industrial Fridge and a Chest Freezer inside the circle cost 0.023 L/h, which is a gas can every 18.1 in-game days. Suppose the generator carrying them is a Lectro-Max, and suppose it arrived pristine. It reaches 40% after 50 days of running and the fire-and-explosion band at 20% after 66.7.

Sixty-seven days at eighteen days a can is 3.7 tanks. About thirty-seven litres of gasoline, poured in four separate trips, before condition ever becomes the thing you have to deal with — and you will have crossed 40% two and three-quarter cans in. Swap the generator and the ratio moves but the shape does not: a Premium Technologies unit stretches the window to 80 days, four and a half cans; a ValuTech collapses it to 53, closer to three.

That is the answer to the question the fuel gauge was quietly refusing to ask. Refuelling is a chore with a fixed rhythm and no jeopardy in it. Repair is the activity that actually binds.

The roll never looks at the load

And here is the part that reverses everything you have just spent six sections learning.

Look at what the hourly tick does with the load figure. For fuel, it takes totalPowerUsing — the raw internal sum behind the panel, every line item you have been auditing and optimising, before the multiplier touches it — multiplies it by the sandbox setting, and subtracts the result from the tank. That is the same multiplication the panel has already performed on its way to the screen. Then it rolls for condition, and that roll reads exactly one number: C. Not the total. Not the line items. Not whether anything is inside the circle at all.

So a generator running an empty disc, powering nothing, connected to a base you stripped weeks ago, wears out at precisely the same rate as one carrying a fridge, a freezer, an oven, a television and every lamp in the house. There is no light load. There are only running hours.

Which means the lever this article has been handing you does nothing here. Switching the oven off saves 0.009 L/h and buys you zero condition. Unplugging the television, deleting the lights, moving the neighbour's fridge out of the circle — every one of those is a real saving on a bill you were never going to struggle to pay, and not one of them adds a minute to the machine's life. The only action that buys condition is switching the generator off, and that is also the only action that saves fuel outright rather than by the drop.

Take that seriously about the things you are running for comfort. Lighting a base is not a fuel decision — six lamps are 5% of a fridge-and-freezer bill, as established. But keeping the generator on for those lamps is a condition decision at full rate, an hour of the machine's finite life per hour of light, and that cost never appeared on the panel because the panel only prices litres. The same goes for a television left running, a charger you finished with, and any evening you left the unit humming out of habit.

The honest limit on all of this is cold storage, and you already know why: the circle's fridges and freezers are the one thing that punishes an off-hour, and it punishes fast — ninety minutes from switch-off to fully thawed. So the off-switch is not a habit you can apply while a freezer is doing real work. It is for the stretches when nothing inside the disc actually needs power: before you move cold storage in, once the freezer is empty, while your food store is jarred rather than frozen, and every hour the generator is running purely so a room is bright.

Watch the Condition line, then, and stop watching Fuel. Fuel is a number you check once a fortnight and act on with a drive you were going to make anyway. Condition is the one counting down whether you are drawing on the machine or not — and both of the numbers it is counting down toward, 40 and 20, are close enough now to be worth knowing what they actually do.

Below 40% It Advertises, Below 20% It Burns — Repair Before Either

They are not two marks on the same scale. Twenty is the number that decides what the generator does to itself. Forty is the number that decides what it does to your base, and it arrives first — roughly seventeen running days first, on the Lectro-Max from the last section — which is why it is the one you should actually be watching for.

Repairs run from the generator’s own right-click menu, and the tooltip names the cost: Scrap Electronics. A 2022 Build 41-era capture; the menu and tooltip text are unchanged in Build 42.

What starts at 40 is backfiring, and the game grades it. Once per running hour, a generator at or under 40% condition rolls one chance in fifteen. At 30% or under, one chance in ten. At 20% or under, one in five. As percentages that is 6.7%, 10% and 20% an hour, and per twenty-four hours of running that is roughly 1.6, 2.4 and 4.8 backfires a day — the first band averaging one every fifteen running hours, the last one averaging one every five.

Those per-hour chances are exact. The day counts built on them are a projection, and it rests on an assumption worth naming once, because every elapsed-time figure in this section inherits it: turning a per-hour chance into a daily rate assumes the roll fires once for every hour that passes, which is how the hourly tick is structured while the generator is actually being simulated. A base you have walked away from is not accounted for the way a base you are standing in is — this guide has already made that point about other people's fuel measurements, and it applies to these numbers too. Read the day counts as what a worn generator does while you are there to hear it.

A backfire is not cosmetic, and it is not a small version of the noise the generator already makes. The running loop is a hum of radius 20 tiles — 23 on a ValuTech, 25 on the Old unit — at volume 20. A backfire fires off a world sound at radius 40, volume 60. Double the reach, which is four times the ground area, so a single backfire is heard across roughly four times the disc the generator powers. Triple the volume. For scale, volume 60 is what the game gives a police lightbar siren — the same loudness, though not necessarily the same reach; a helicopter is 500. Your generator is not the loudest thing that will ever happen in Knox County. It is comfortably the loudest thing your base produces on its own, and past 40% it produces it on a schedule you do not control.

Put that against the condition timeline and the size of the problem becomes obvious. A pristine Lectro-Max reaches 40% at fifty running days and the 20% band at 66.7 — about seventeen running days in between, at 1.6 backfires a day until it crosses 30 and 2.4 a day after that. Cross 40 and simply keep running, and you have signed up for something north of thirty siren-volume events, none of them at a time of your choosing, every one of them announcing a fixed position that has your food in it.

There is no muffling your way out of it, either, and the mechanism is worth knowing even though the conclusion belongs to the setup guide. The generator's own square being inside a room halves its running noise radius — a fix that shipped in 42.13.0 — so walls really do quieten the hum. But a room is also exactly what poisons you: the toxicity flag is set with building.setToxic(isActivated()), applied to the whole building rather than the tile, and 42.13.0 also made this fire retroactively for player-made rooms as roofs go up. Put a roof over your generator and you have not built a sound baffle, you have made the structure it stands in toxic. The quiet placement and the survivable placement are opposites, which is why the setup guide's outdoor rule is the right one; and note that the halving is documented against the running hum specifically — nothing establishes it for the backfire event, and nothing establishes that a player-built roof alone triggers it.

Twenty is not a warning, it is the band

Be precise about the boundary, because the wording invites the wrong reading. The reference tables say a generator can catch fire or explode "lower than or equal to 20%", and the code test is condition <= 20. Not approaching 20, not under 20. The moment your panel reads 20, you are inside it.

Inside it, the hourly tick does something it has never done before. It rolls one chance in ten to start a fire — a real one, seeded with an energy value of 1,000, in whatever the generator happens to be standing beside — and failing that, one chance in twenty to explode. Those compound: 0.1 plus 0.9 × 0.05 is a combined 14.5% chance of catastrophic failure per running hour.

That number does not behave like the wear rolls you have been reading about. Survive an hour with probability 0.855 and the arithmetic runs away quickly — projected, as above, on one roll for every elapsed running hour:

• Median survival: 4.4 running hours. Half of all generators sitting at 20% would be gone inside four and a half hours of running.
• Mean survival: 6.9 hours.
• Probability of surviving a full running day: 0.855²⁴ = 2.3%. Ninety-seven times in a hundred, a generator left at 20% does not see out twenty-four hours of operation.

So the two thresholds are not points on a slope. At 40 you have seventeen running days of increasingly loud warning. At 20 every running hour is a 14.5% roll against the machine — an afternoon, on the projection above, and the odds are against the afternoon.

However it ends, it ends the same way. Fuel exhausted calls setActivated(false); condition reaching zero calls setActivated(false); and a fire or an explosion sets condition to zero on its way out, which switches the unit off as well. There is no state where you come back to a generator sitting at 19% waiting to be topped up. A failed generator is a repair from zero — plus whatever the fire did to the building it was standing next to, and plus the ninety minutes your freezer took to give everything back.

What it costs to not let that happen

One Scrap Electronics restores 4% + (0.5 × your Electrical level), which at Electrical 3 — the level that autolearns the connection recipe anyway — is 5.5% per piece. Eighty points of recovery, from the fire band back to full, therefore costs 15 pieces. And that is the expensive version, because you let it get there:

Read the first two rows against each other and the whole argument of this section is sitting in the difference: four pieces of scrap. Eleven instead of fifteen. That is the entire price of never being in the fire band, and what it buys is thirty-odd unscheduled noise events you do not broadcast, and a 14.5%-an-hour failure roll you never make.

Each operation also returns 1.25 Electrical XP, so the repairing quietly feeds the skill that makes repairing cheaper — slowly, at under nineteen XP for the eighty-point job, but in the right direction. Every level you gain adds another half a point to what each piece is worth, which is why the same eighty-point job that costs fifteen pieces at Electrical 3 costs nine at 10.

The line to hold

Repair at 40, not at 20.

Below 40 the machine is not failing, and that is precisely the trap — it powers everything it powered yesterday, at the same 0.023 L/h, with the same eighteen days on the can. Nothing on the panel deteriorates. What has changed is that it has begun announcing your position at siren volume every fifteen hours, and that the next threshold down is not another warning but the band where it burns.

So keep Scrap Electronics banked against that number specifically. Eleven pieces covers a full recovery at Electrical 3, and every level you put into the skill makes each piece go further — a stack of a dozen sitting in the same crate as the gas can is a maintenance plan, and it costs you nothing to hold. Then check Condition on the same schedule you check Fuel, which is to say whenever you happen to open the panel, because on a Lectro-Max running eight hours a day, 40% is months of real survival away and will still arrive when you are not looking.

And switch the unit off whenever nothing inside the circle is doing work worth paying for. Condition is spent by the running hour and never by the load, so an off-switch is the only thing in this entire guide that buys you any of it back.

Two gauges, and you have been watching the wrong one. Fuel only ever decided whether dinner stayed cold. Condition decides whether the generator is still there — and whether the base around it is.