Battery

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Revision as of 02:28, 16 November 2022 by Hordes (talk | contribs) (format standardization & remove lots of redundant info)
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Battery

Battery

Stores electricity for later use. Charged batteries explode when exposed to rain or fire.

Base Stats

Type
BuildingPower
Market Value
200 Silver [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
Steel 70 + Component 2
Deconstruct yield
Steel 35 + Component 1
Destroy yield
Steel 17 - 18 + Component 0 - 1
Technical
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.

Batteries connect directly to the wind turbine and the attached coolers, with no conduits. This power grid will only "Zzztt" if the batteries get rained on.

Analysis

Batteries are useful in most colonies, even if the colony does not rely on unstable power sources like solar panels and wind turbines.

If only renewable energy is used, at least one battery is mandatory, because sufficient power supply can never be guaranteed. Solar panels produce no power during the night and during an eclipse, and wind turbines are completely unreliable. If the colony has no other backup power source, it is highly recommended to keep some additional batteries behind a power switch on a separate network (see Hazards above), so they can be brought online in the case of a short circuit event.

Alternatively, some batteries can also be stored in a warehouse, and then placed down anywhere on the power grid on demand. This makes switches unnecessary.

Batteries can also be used to make fueled generators more economical. These generators provide constant power, but they also burn their fuel at a constant rate – no matter how much power is actually used. If you connect some batteries, you can at least catch half of the otherwise wasted energy, and then disable the generator until the batteries run dry. This will save 100% of the fuel for the time the generator is offline. This is especially helpful in the early game, where you might not even have enough power draw to fully load a single generator, and fuel will be usually scarce as well.

The energy stored by even a single battery is very 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, or 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 you calculate the battery capacity that is necessary when using renewable energy, keep in mind that charge efficiency is only 50%. That is, only half of any excess energy will be effectively usable. This is particularly relevant when planning a greenhouse setup, of hydroponics basins and a sun lamp. The sun lamp will draw 2900 W during the day, and 0 W during the night, for an average demand of 1450 W. However, it is not sufficient to generate only 1450 W at all times, hoping that a 3-battery array will even out the difference in power draw. This is because during the night, only half of the extra 1450 W will effectively charge the batteries, storing 8,700 Wh of energy (~360 Wd). This will only be enough to power the sun-lamp for 6 hours during the day. For the remaining 6 hours, the missing 1450 W will have to be provided by other means (usually a solar panel). Simply adding more batteries will not change this. Two batteries will provide enough buffering in this scenario.

The example setup, including 24 hydroponics basins, can be fully powered by one geothermal generator and a solar panel, connected to a single buffer battery.

Even in colonies that do not use wind or solar energy, batteries are useful to cover spikes in power usage, usually caused by turret arrays and devices like crematoriums, smelters and mineral scanners that are only brought online intermittently. 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 that would cover this, even a single charged battery can power this entire setup for more than 4 in-game hours. An array of 5 batteries can power the defenses for an entire in-game day. The battery array should be isolated with two power switches from the security grid and main power grid. This makes it then also very easy to power the entire setup with a single switch, as well as keep the batteries safe from the short circuit event.


Version history

  • 0.0.245 - Charged batteries now explode while burning.