Batteries stores excess energy converted by Transformers for emergencies or to be used as an export. Must be placed adjacent to a transformer to function. A maximum of 10 Batteries can be placed around a transformer.
In total, a battery can store up to 12000 unit x hour of power when weather is off but only 6000 unit x hour of power with weather on.
Selling the power stored in a fully charged battery yield $500.