Any must match electricity production to consumption, both of which vary significantly over time. Energy derived from and varies with the weather on time scales ranging from less than a. Electricity can be stored directly for a short time in capacitors, somewhat longer electrochemically in, and much longer chemically (e.g. hydrogen), mechanically (e.g. pumped hydropower) or as heat. The first. The (LCOS) is a measure of the lifetime costs of storing electricity per of electricity discharged. It includes investment costs, but also operational costs and charging costs. It depend. • • • (ESaaS)•.