Battery
Battery
Stores electricity for later use. Charged batteries explode when exposed to rain or fire.
Base Stats
- Market Value
- 200
[Note] - Mass
- 20 kg
- Beauty
- -15
- HP
- 100
- Flammability
- 100%
- Path Cost
- 50
Building
- Size
- 1 × 2
- Minifiable
- True
- Placeable
- True
- Passability
- pass through only
- Cover Effectiveness
- 40%
- Blocks Wind
- True
- Terrain Affordance
- Medium
- Efficiency
- 50%
Creation
- Required Research
- Battery
- Work To Make
- 800 ticks (13.33 secs)
- Resources to make
70 + 
2- Deconstruct yield
- 35 + 1
- Destroy yield
- 17 - 18 + 0 - 1
- thingCategories
- BuildingsPower
The battery is an electric device that stores power to use when needed.
Summary
Each battery can store 600 Wd (Watt-days) of power at once. 1 Watt-day is equal to powering a 1 W appliance for 24 hours. However, batteries have a 50% efficiency, meaning they take in only half of a grid's excess power. Power is evenly divided between all connected bateries. There is no limit or penalty for power output. Each tile of battery will also transfer an infinite amount of power through it, as if it were a power conduit. Therefore, electric appliances can connect within 6 tiles of a battery, but a battery can't connect in the same way.
Batteries automatically charge and discharge when connected to power. They can't be turned off, but a power switch can disconnect them from the main grid. While installed, batteries lose 5 W of power per day, even if they aren't connected to anything. Batteries can be uninstalled, which preserves their power for a new location.
An installed battery will short-circuit (the Zzzt... event) if left in the rain or snow without a roof. Storing power also makes the random short-circuit more dangerous, though a battery-only grid is immune to the random event.
Analysis
Batteries are most useful when using wind turbines or solar panels, both which are highly variable power sources. Using a battery creates a 'cushion', making their power more reliable. For instance, a battery is required to use any sort of solar power at night or during an eclipse. Meanwhile, fueled generators are consistent - they'll burn their fuel at a constant rate, even if it would be wasted. While you could just turn the generator off, colonists need to walk to the generator. Using a battery can help save on both fuel and micromanagement.
Even in colonies that do not use wind or solar energy, batteries are useful to cover spikes in power usage, such as short-circuits, turret arrays, electric smelters. A battery can cover arbitrarily high power needs, the size of the array only changes for how long that is possible. As an example, an array of 20 mini-turrets and 4 autocannon turrets draws 3200 W of power. Instead of building another geothermal generator, each battery will power this for more than 4 in-game hours.
Uninstalled batteries can be used whenever power needs to be transported. They can be used to power remote deep drills, or even put on a caravan. This allows for electric appliances like mini-turrets to be used in offensive operations.
Efficiency
When calculating power capacity, keep in mind that charge efficiency is only 50%; half the excess energy is lost. This is particularly relevant when planning a sun lamp setup. The lamp draws 2900 W during the day, and 0 W during the night, for an average demand of 1595 W. However, an average power of 1595 W is not sufficient, and only enough to power the lamp for 6 hours. Simply adding more batteries will not change this; 2 batteries are sufficient.
Power storage
It is highly recommended to keep some additional batteries behind a power switch on a separate network, so they can be brought online in the case of a short-circuit event. Alternatively, you can uninstall batteries and keep them in a warehouse. You'll have to reinstall them manually, but they won't discharge. In practice, the discharge is negligable.
The energy stored by even a single battery is fairly high. 600 Wd are enough to power, for example, three coolers at full power draw for an entire day, with no other source of power available. Therefore, building a lot of batteries ("just to be safe") is not necessary, and possibly even harmful. Unless you take complex and expensive measures to avoid the short-circuit event, having too many batteries online is a liability. Examine closely how much energy storage you need, and do not build more than that.
When powering a security array, the battery group should be isolated. There should be 1 power switch to the main power grid, turned off when you are done charging. And 1 power switch should connect to the security grid, where 1 flick will turn on all your turrets. This also keeps your power safe from a short circuit.
Version history
- 0.0.245 - Charged batteries now explode while burning.
- Power
- Power conduit (Waterproof) • Power switch • Wood-fired generator • Chemfuel powered generator • Wind turbine
- (research)
- Battery • Geothermal generator • Solar generator • Watermill generator • Toxifier generator
- (uncraftable)
- Vanometric power cell • Unstable power cell
- Related
- Ship reactor