Accumulator
Overview
An Accumulator is a placeable power storage building that holds up to 540 MJ of energy. It is unlocked early enough to become one of the main tools for smoothing out factory power demand, especially before more advanced large-scale generation is available. In normal use, placed Accumulators store excess grid power and later supply that power back to the grid when production falls short. They are commonly paired with Solar Panels, since solar output is only available during the day, allowing a factory to continue operating at night from stored energy.
When an Accumulator becomes completely full, it turns into a Full Accumulator. A Full Accumulator keeps its charge in storage, can be used as fuel for 
Icarus, and can be transported by logistics for interplanetary power exchange. Picking up a partially charged Accumulator causes it to lose its charge, so only fully charged units are worth storing or shipping. Full Accumulators are also a required component of Orbital Collectors. Energy Exchangers can charge Accumulators and discharge Full Accumulators at high speed, making them the standard infrastructure for moving large amounts of power between locations.
Charging and discharge rates depend on how the Accumulator is being used:
- Placed on the ground: charges at 1.5 MW and discharges at 2.25 MW.
- In an
- Used as fuel: the discharge rate depends on the Energy Circuit upgrade.
A fully charged Accumulator can be used directly as Icarus fuel, and it is extremely dense energy storage for that purpose. A stack of charged Accumulators provides a very large reserve, making them especially valuable for long expeditions or for replacing lower-density fuels once production is established. Because they can be proliferated, Accumulators can also be improved for Energy Exchanger use: 
A useful way to monitor grid health is to place even a single Accumulator on a planet and watch the Statistics Panel. If power satisfaction stays at 100%, the Accumulator will charge and remain full; if satisfaction drops below 100%, it begins discharging, and the battery graph will show the deficit clearly. This method does not work well on planets powered by Energy Exchangers, since they continually charge and discharge Accumulators and can obscure the signal.
The Accumulator is crafted from iron ingots, super-magnetic rings, and crystal silicon. Its recipe reflects its role as an early but important piece of power infrastructure: simple enough to mass-produce, yet powerful enough to stabilize an entire planetary grid.
