Space Engineers is a building game where you design ships, stations and rovers out of individual blocks. Power blocks are the parts that make or store the electricity those builds need to function. The game offers reactors, hydrogen engines, solar panels, wind turbines and batteries, and each one has its own strengths and limits. Knowing those limits is the key to building a setup that keeps everything running.
Power Source
Reactors
Small Reactor
Makes electricity by burning uranium ingots.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 500 kW; large grid: 15 MW
- Max Stored Power
- -
- Fuel and Conditions
- Uranium ingots; needs conveyor access to refuel.
- DLC Pack
- Base game
Large Reactor
Makes high output by burning uranium ingots.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 14.75 MW; large grid: 300 MW
- Max Stored Power
- -
- Fuel and Conditions
- Uranium ingots; needs conveyor access to refuel.
- DLC Pack
- Base game
Small Warfare Reactor
A Warfare 2 visual style for the Small Reactor.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 500 kW; large grid: 15 MW
- Max Stored Power
- -
- Fuel and Conditions
- Uranium ingots; needs conveyor access to refuel.
- DLC Pack
- Warfare 2 Pack
Large Warfare Reactor
A Warfare 2 visual style for the Large Reactor.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 14.75 MW; large grid: 300 MW
- Max Stored Power
- -
- Fuel and Conditions
- Uranium ingots; needs conveyor access to refuel.
- DLC Pack
- Warfare 2 Pack
Prototech Fusion Reactor
Makes very high electrical output from hydrogen on large grids.
- Grid Sizes
- Large grid only
- Max Output
- Large grid: 400 MW
- Max Stored Power
- -
- Fuel and Conditions
- Hydrogen, up to 1,000 L/s; stops burning fuel when the grid idles; needs a Prototech Frame to build or can be recovered from a Factorum encounter.
- DLC Pack
- Base game
Power Source
Hydrogen Engines
Hydrogen Engine
Turns hydrogen into electricity for ships and stations.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 500 kW; large grid: 5 MW
- Max Stored Power
- -
- Fuel and Conditions
- Hydrogen; needs powered conveyor access to tanks or an O2/H2 Generator; another power source is needed to start it.
- DLC Pack
- Base game
Sci-Fi Hydrogen Engine
A Core Systems visual style for the Hydrogen Engine.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 500 kW; large grid: 5 MW
- Max Stored Power
- -
- Fuel and Conditions
- Hydrogen; needs powered conveyor access to tanks or an O2/H2 Generator; another power source is needed to start it.
- DLC Pack
- Core Systems Pack
Power Source
Wind Turbines
Wind Turbine
Generates renewable power from wind at a planetary station.
- Grid Sizes
- Large grid only
- Max Output
- 400 kW (average weather)
- Max Stored Power
- -
- Fuel and Conditions
- Needs a stationary large-grid build on an atmospheric planet, wind and open clearance; produces no power in space, on mobile grids or on airless moons.
- DLC Pack
- Base game
Twin-Blade Wind Turbine
A larger Decorative Pack 3 turbine with the same power output as a Wind Turbine.
- Grid Sizes
- Large grid only
- Max Output
- 400 kW (average weather)
- Max Stored Power
- -
- Fuel and Conditions
- Needs a stationary large-grid build on an atmospheric planet, wind and open clearance; produces no power in space, on mobile grids or on airless moons.
- DLC Pack
- Decorative Pack 3
Power Source
Solar Panels
Solar Panel
Makes power when its panel faces direct sunlight.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 40 kW; large grid: 160 kW
- Max Stored Power
- -
- Fuel and Conditions
- Needs direct sunlight; output changes with angle, shadows, weather and planetary day/night.
- DLC Pack
- Base game
Colorable Solar Panel
A paintable surface version of the Solar Panel.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 40 kW; large grid: 160 kW
- Max Stored Power
- -
- Fuel and Conditions
- Needs direct sunlight; output changes with angle, shadows, weather and planetary day/night.
- DLC Pack
- Decorative Pack 3
Colorable Solar Panel Left
A triangular paintable panel that joins the other Colorable Solar Panels.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 20 kW; large grid: 80 kW
- Max Stored Power
- -
- Fuel and Conditions
- Needs direct sunlight; output changes with angle, shadows, weather and planetary day/night.
- DLC Pack
- Decorative Pack 3
Colorable Solar Panel Right
A triangular paintable panel that joins the other Colorable Solar Panels.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 20 kW; large grid: 80 kW
- Max Stored Power
- -
- Fuel and Conditions
- Needs direct sunlight; output changes with angle, shadows, weather and planetary day/night.
- DLC Pack
- Decorative Pack 3
Power Source
Batteries
Battery
Stores electricity and releases it when the grid needs power.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 4 MW; large grid: 12 MW
- Max Stored Power
- Small grid: 1 MWh; large grid: 3 MWh
- Fuel and Conditions
- No fuel; charges from other power sources and stores power for later use.
- DLC Pack
- Base game
Small Battery
A compact battery for small-grid builds.
- Grid Sizes
- Small grid only
- Max Output
- 200 kW
- Max Stored Power
- 50 kWh
- Fuel and Conditions
- No fuel; charges from other power sources and stores power for later use.
- DLC Pack
- Base game
Prototech Battery
Stores more power and transfers it between batteries more efficiently.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 2.8 MW; large grid: 48 MW
- Max Stored Power
- Small grid: 2 MWh; large grid: 18 MWh
- Fuel and Conditions
- No fuel; charges from other power sources; a Prototech Frame is needed to build it; 90% efficient when charging from another battery.
- DLC Pack
- Base game
Warfare Battery
A Warfare 2 visual style for the Battery.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 4 MW; large grid: 12 MW
- Max Stored Power
- Small grid: 1 MWh; large grid: 3 MWh
- Fuel and Conditions
- No fuel; charges from other power sources and stores power for later use.
- DLC Pack
- Warfare 2 Pack
Battery Bank
A compact battery design with different capacity by grid size.
- Grid Sizes
- Small and large grids
- Max Output
- Small grid: 4 MW; large grid: 6 MW
- Max Stored Power
- Small grid: 1 MWh; large grid: 1.5 MWh
- Fuel and Conditions
- No fuel; charges from other power sources; the large-grid bank stores half a standard Battery's capacity at half the size.
- DLC Pack
- Prosperity Pack
Battery Bank Offset
A large-grid Battery Bank variant with an offset module layout.
- Grid Sizes
- Large grid only
- Max Output
- 6 MW
- Max Stored Power
- 1.5 MWh
- Fuel and Conditions
- No fuel; charges from other power sources; large-grid offset form of the Battery Bank.
- DLC Pack
- Prosperity Pack
What Power Blocks Do in Space Engineers
Nearly every working part of a build needs power. A grid, which is any connected group of blocks such as a ship, station or rover, needs electricity to run its thrusters, gyroscopes, doors, lights, air vents and artificial gravity. In Survival mode, your suit's life support needs power too.
How Power Flows Through Your Build
Power moves through blocks that touch each other, so you never have to lay cables. Everything in a connected grid shares one pool of power, no matter which block produces it. The game also decides which source gets used first. Solar panels and wind turbines go first, batteries come next, and reactors are used last, so uranium only gets burned when the other sources can't keep up.
Reactors: Big Output, Limited Uranium Fuel
Reactors give more power than any other standard power source, and they work in space and on any planet. A Large Reactor on a large grid far outstrips the others, which makes it the usual choice for big stations and long trips where you can't count on the weather.
The catch is fuel. Only uranium ingots can fuel one, and uranium is rare and slow to refine, so plan your supply before you commit to a reactor.
Hydrogen Engines: Steady Power From Ice
Hydrogen engines turn hydrogen into electricity, and they run regardless of sunlight or wind. That makes them the dependable choice for ships, stations and vehicles where solar and wind would fall short. Fuel reaches the engine through conveyors, from tanks you refill at a connector, from an O2/H2 Generator fed with ice, or from both. The engine can't take ice on its own, so a ship or station without tanks needs that generator.
Ice is common on planets and asteroids, which makes hydrogen practical in many places. Tanks and conveyor lines take up a lot of room, and a damaged tank is explosive, so plan the layout before you build. The engine also scales its fuel use to match demand, so a quiet grid burns far less hydrogen than a busy one.
Solar Panels and Wind Turbines: Free Power With Conditions
Solar panels and wind turbines burn no fuel, so they add power without any hauling. Solar panels work in space and in daylight on planets, but they make nothing at night, since the ground blocks the sun. Weather and shadows from nearby ships or asteroids can dim them, and they produce the most when they face the sun straight on. Mounting them on a rotor and hinge lets them follow the sun through the day.
Wind turbines are pickier. They only produce power on planets with an atmosphere, and only on large grid stations, so they stay silent on ships and rovers. Their output depends on how high they sit, how thick the air is, what nearby blocks or terrain get in the way, and the weather. A turbine on the ground performs poorly, so raising it on pillars helps, and one attached to a station through a rotor, hinge or piston stops producing.
Batteries: Storing Power for Later
Batteries don't make power. They store the surplus from your producers when the grid is taking in more than it uses, then release it quickly when demand rises. That's what keeps a grid running when its producers fall quiet. New batteries start about 30 percent charged, so they need another source to fill up.
Each battery has three modes. Automatic is the default, charging from spare power and discharging when the grid needs it, which suits most ships and bases. Recharge pulls power in from other sources, including other batteries, and it stops feeding the grid, so don't leave it on while you're flying. Discharge only feeds the grid and stops the battery from charging.
Storing power costs you some of it. Charging from a reactor loses roughly a fifth of the energy, and moving power from one battery to another loses about the same. A full battery at full output lasts about 15 minutes, and a drained one adds weight without adding power until it's recharged, so large banks suit short trips better than long ones.
How to Get and Unlock Power Blocks
You build every power block from components, so the real work is gathering materials. Costs vary a lot. Reactors are the most expensive, hydrogen engines sit in the middle, and solar panels, wind turbines and batteries are the cheapest.
If progression is turned on in your game, some blocks stay locked until you build the right machine first. A Basic Assembler unlocks batteries, while solar panels and wind turbines are usually available from the start. Some reactors and batteries also come in Warfare versions that work the same way but need the Warfare 2 Pack DLC.
Choosing the Right Power Setup in Space Engineers
The Large Reactor and the battery matter most. The reactor provides the bulk of the power in big builds, and the battery is the one piece almost every build needs because it smooths out the gaps between sources. For ships and bases away from a reliable sun or wind, a hydrogen engine is a strong second choice wherever ice is nearby. Solar panels and wind turbines are best treated as a free supplement that cuts down on fuel use.
Before you rely on a setup, check how much your producers can make in the control panel, then leave some margin above what the grid normally uses. Running right at the limit leaves nothing spare for the moment a big draw starts.
FAQ
How much uranium does a reactor use?
One uranium ingot holds 1 MWh of energy. A Large Reactor at full output on a large grid burns one kilogram of uranium about every 12 seconds, while the same reactor on a small grid, at its lower maximum, takes roughly four minutes per kilogram. Reactors rarely run at full output for long, so a supply usually lasts far longer than those figures suggest.
Why isn't my hydrogen engine getting fuel?
Start with the conveyor line between your tanks or generators and the engine. Make sure it's unbroken and that the tanks aren't set to stockpile. If your O2/H2 generators are empty, load them with ice from a cargo container. If the whole grid has gone dead, the conveyors can't start moving fuel, so add a battery or solar panel, or connect to another powered grid, to give them a small charge.
How do I keep my ship powered when I log off a multiplayer server?
Set your batteries to Automatic before you leave, so they store whatever power comes in. Add solar panels or wind turbines to keep topping them up while you're away, and switch off power-hungry machines such as assemblers and refineries. Together, these steps keep the grid powered while you're gone.