Abstract
The energy storage system (ESS) is the next major disruption to the current architecture of
the electricity grid. Energy storage offers several benefits to the electricity grid, which include frequency
regulation, energy arbitrage, peak shaving, reducing intermittency of renewable energy sources (RESs),
and many other benefits that are not possible without large energy storage. Large-scale batteries are still
expensive and cannot be readily used with a reasonable return on investment. Aggregating a large number
of consumers’ small scale batteries may provide us with the benefits of large central storage. However,
aggregated small-scale batteries have several advantages over large central storage. Small-scale batteries
provide better scalability and open up many new investment opportunities for the grid as well as for the
consumers. In this article, we present a control scheme for small-scale distributed batteries, namely, Weighted
Batteries Scheduling (WBS) scheme to make a large distributed energy storage. We also present a method
to calculate weights, that are required for the WBS scheme, by prioritizing the batteries with respect to
the state-of-charge (SOC). We evaluate the fairness of the proposed scheme using Jain’s fairness index and
entropy-based fairness index. The proposed storage model can be used for any necessary support for the
electricity grid. We study financial benefits obtained by the large distributed energy storage for frequency
regulation, energy arbitrage and peak shaving. Frequency regulation appears to be of the highest value for
energy storage. Our results show that a distributed storage consisting of 1000 small batteries each of 1 kW
power achieves average daily revenue of $606.61.