Project Zomboid Generator Guide: Fuel, Noise, Repair

Verified against: Build 42.20.3, the stable hotfix released on 17 August 2026. Figures below come from PZwiki and from in-game item scripts retrieved at Build 42.20.0. Patches 42.20.1 through 42.20.3 covered multiplayer, memory and lighting fixes; no generator changes were announced. 42.20.3 STABLE Hotfix Released (The Indie Stone forums)

Short answer: put the generator outdoors on the ground, unlock the Connect option by reading How to Use Generators (or reaching Electrical 3, or starting as an Electrician), fuel it from a gas can while it is switched off, and never let its condition drop to 20% or it can catch fire. Everything else is detail — but the details moved in Build 42, because there are now four generator models with different noise radii and different failure rates, where Build 41 only ever had one.

What unlocks the Connect Generator option

Finding a generator is not enough; you cannot wire it into a house until your character qualifies. Per PZwiki's Generator page, any one of the following is enough.

• Read the magazine How to Use Generators (item ID Base.ElectronicsMag4). It turns up on bookshelves, in bookstores, in school libraries and in mailboxes. This is the realistic early-game route.
• Reach Electrical level 3. Electrical only levels from dismantling electronics and furniture with a screwdriver and from repairing generators, so grinding to 3 before the power cuts is usually slower than looting the magazine.
• Start as an Electrician. The occupation can connect generators from day one.

PZwiki additionally lists the Engineer occupation, and Electrical level 2 when your character has the Inventive trait. That page was last updated for Build 42.13.1 and has not been re-verified against 42.20.3, so if you are building a character specifically around one of those routes, read the occupation and trait descriptions on the character creation screen before you commit points to it.

Placing, connecting and fuelling, step by step

1. Carry it. Pick it up from the context menu. A generator never enters your inventory — your character hauls it in both hands (RequiresEquippedBothHands = true in the item script). You cannot attack while carrying one, equipping a weapon drops it on your tile, and you move slower. Drive a vehicle close before you start walking with it.
2. Set it down outdoors. Generators only work placed on the ground, and the ground you choose must be outside. See the next section for why this is not optional.
3. Connect it. Right-click and choose "Connect Generator" to wire it into the building's power system. This is the step that requires the magazine, skill or occupation above.
4. Fuel it. Right-click and choose "Add Fuel". You can only fuel a generator while it is switched off.
5. Switch it on from the same context menu.

Running one indoors will nearly kill you

PZwiki states plainly that you should not place a generator inside a structure you occupy or plan to occupy. Generator exhaust drives your character's health down to 1 very quickly. Stepping outside stops the damage, but the building stays unsafe until the generator is turned off. If you want it under cover, use an open porch or a lean-to that still counts as an exterior tile rather than a walled room.

Power radius: 20 tiles, three floors up and down

A running generator powers a cylinder centred on itself: radius 20 tiles horizontally, three floors above and three floors below — a cylinder 7 floors tall with a base 41 tiles across. A generator sitting outside a two-storey house will reach the lights and fridge upstairs. A generator hidden in a barn 25 tiles away will power nothing in your base.

All four Build 42 generators compared

Build 42 shipped four models. They differ in weight, how fast they degrade and how far the noise carries. Values below are from item scripts retrieved at Build 42.20.0.

The durability column is the script value ConditionLowerChanceOneIn: the higher the number, the less often the generator loses condition. Premium Technologies is the all-round pick, ValuTech is the one you can actually carry any distance but it wears out fastest, and Old is the one to leave behind if your base sits inside a suburb — noise pulls zombies.

How long a tank lasts

A generator burns fuel just by running, and every powered appliance inside the radius adds load. Baseline consumption with no load is 0.002 L/h. The figures below are per tile, so a two-tile popsicle freezer draws 0.016 L/h.

Runtime is simply fuel remaining in litres divided by total draw in L/h, measured in in-game hours. PZwiki's worked example: a popsicle freezer (0.016) plus a television (0.003) plus six lamps (0.0012) plus baseline (0.002) totals 0.0222 L/h, so a full 10 L tank runs roughly 450 in-game hours — about 18.7 days.

Rather than memorising the table, right-click the generator and open "Generator Info". It lists total load and the demand of each connected device, which is the fastest way to find the appliance quietly draining your fuel.

One caveat on tank size. The Generator page treats a full tank as 10 L in its worked example, while the Gas Can page says one full 10 L can refills 80% of a generator's tank. Those two statements do not agree, and both pages were last updated for 42.10.0-42.13.1, older than the current build. Check the actual level in Generator Info. Either way the practical conclusion holds: one full gas can very nearly fills a generator. You cannot siphon fuel back out of a generator, but fuel stays in the tank if you pick it up and move it elsewhere.

Repair it before it burns your base down

Condition drops as the generator runs. At or below 20% condition, a generator can catch fire or explode. A generator parked against your base wall is an ignition source, so check its condition on a schedule rather than when it starts sputtering.

Repairs use Scrap Electronics. Each repair operation consumes one Scrap Electronics and restores 4% + 0.5 x your Electrical level. That is 4% per operation at Electrical 0 and 7% at Electrical 6. Each operation also grants 1.25 Electrical XP, so maintaining generators is itself one of the two ways the skill levels — which is a good argument for topping up condition early instead of waiting for a crisis.

Scrap Electronics comes from dismantling electronic devices with a screwdriver. PZwiki notes that industrial kitchen buildings, dense with dismantlable appliances, are the best places to farm Electrical XP generally.

Sandbox settings that change all of this

Everything above assumes default settings. On a public server or a custom sandbox, check these first.

• Generator Fuel Consumption: multiplier on fuel burn. Default is 1; set it to 0 for generators that never need refuelling (maximum 100).
• Generator Spawn: how often generators spawn on the map.
• Generator Working In Exterior: on by default. Generators function on exterior tiles, which is what lets you power a gas station pump and keep drawing its fuel reserves after the grid dies.
• Electricity Shutoff: the range of days within which the power cuts. There is no fixed "day X" answer to when the grid goes down.

What changed since Build 41

Generators were reworked in Build 42, and the item script history shows exactly how.

• One model became four. Through Build 41 there was a single generator, Base.Generator, added back in Build 32.14 and simply called "Generator". Build 42.0.0 added Premium Technologies, ValuTech and Old, and renamed the original to "Generator - Lectro-Max", which became "Generator - Lectromax" in Build 42.8.0.
• Per-model wear was introduced. ConditionLowerChanceOneIn was added in Build 42.0.0. Before that there was no durability difference to choose between.
• Noise became model-specific, then was rebalanced. Build 42.1.0 gave each model its own sound radius and volume; Build 42.4.0 cut Old from 30 to 25 tiles and ValuTech from 25 to 23.

The practical upshot: the Build 41 habit of grabbing the first generator you trip over now costs you something. Which model you haul home determines how much noise your base makes and how much Scrap Electronics you burn keeping it alive.

Where to find one

Generators most often appear in warehouses, garages, tool sheds and self storage facilities — room definitions shed, garagestorage and storageunit. Exact spawn chances shift heavily with loot settings and elapsed in-game days, so no percentages are quoted here.

PZwiki also lists several map locations with guaranteed generators, including the military blockade near Louisville, the Echo Creek festival zone and the Doe Valley secret bunker. All of them sit in high zombie density, so bring a vehicle and plan the way out before you go.

Checklist

• Unlock connecting with the How to Use Generators magazine, Electrical 3, or the Electrician occupation.
• Place it outdoors on the ground. Indoors, exhaust takes your health to 1.
• Power reaches 20 tiles horizontally, three floors up and three down.
• Baseline burn is 0.002 L/h; read real numbers from Generator Info.
• Repair with Scrap Electronics well before condition reaches 20%.
• Four models in Build 42 — pick for noise and durability, not colour.

Sources

• PZwiki: Generator (radius, consumption, repair, connection requirements; page last updated for Build 42.13.1)
• PZwiki: Magazine: How to Use Generators
• PZwiki: Electrical (repair amount and XP per operation)
• PZwiki: Gas Can
• PZwiki: Sandbox (generator world settings)
• The Indie Stone: 42.20.3 STABLE Hotfix Released