Accumulator

Accumulators are electricity-storage buildings used to store and release electrical energy in the power grid. Each accumulator holds 5 MJ of energy and has a maximum charge and discharge rate of 300 kW. They are commonly used with solar power to store daytime surplus and supply power at night, to provide short-term surge power for transient loads, and to act as emergency backups during blackouts.

Because an accumulator’s input/output rate is limited, multiple accumulators are typically deployed in banks to increase total stored energy and delivery rate. At the stated rates, 20 accumulators (100 MJ) are sufficient to supply 1 MW for the night if properly sized; for balanced solar setups the practical ratio is roughly 25 solar panels per 21 accumulators (panels sized to the same generation assumptions). A full 5 MJ accumulator charging or discharging at its maximum takes about 17 seconds.

Accumulators interact with the electrical network’s priority rules: they receive power only after all higher‑priority consumer demands are satisfied and have a lower delivery priority than other entities. This behavior enables several advanced uses:

• Shared accumulator banks can bridge two isolated power networks without directly connecting them. By connecting distinct sets of electric poles from two networks to the same accumulator group while keeping the poles of the two networks unconnected, the accumulators will charge from either network when that network has surplus and can discharge into either network when it requires power. Total transfer between networks is limited to 300 kW per accumulator.
• The network-isolation technique lets you limit and prioritize power delivery. Place critical infrastructure (generators and high‑priority loads) on one network and non‑critical systems on another that shares accumulators. Non‑critical networks will only receive power when surplus exists on the critical network, and the delivery rate is capped at 300 kW per accumulator—effectively throttling low-priority consumption during shortages.
• Accumulators smooth short surges in demand, supplying temporary power until production catches up or the demanding device reduces consumption or shuts down.

Practical notes and behavior details:

• If multiple poles deliver or draw power unevenly from the same accumulator group without proper connectivity, discharge can be distributed unevenly; some loads may receive full demand while others receive none.
• Accumulators produce light while charging and discharging, which can help visually indicate grid activity.
• They are suitable as emergency backups to keep a factory running briefly during a blackout and are essential for solar‑only bases to remain powered through the night.
• For unlimited throughput between networks, a power switch is a better option than relying solely on accumulator transfer limits.