You might only think about energy storage when your laptop or cellphone are running out of juice, but utilities can plug bigger versions into the electric grid. And thanks to rapidly declining lithium-ion battery prices, using energy storage to stretch electricity generation capacity.
Based on our research on energy storage costs and performance in North Carolina, and our analysis of the potential role energy storage could play within the coming years, we believe that utilities should prepare for the advent of cheap grid-scale batteries and develop flexible, long-term plans that will save consumers money.
Peak demand is pricey
The amount of electricity consumers use varies according to the time of day and between weekdays and weekends, as well as seasonally and annually as everyone goes about their business.
Those variations can be huge.
For example, the times when consumers use the most electricity in many regions is nearly double the average amount of power they typically consume. Utilities often meet peak demand by building power plants that run on natural gas, due to their lower construction costs and ability to operate when they are needed.
However, it’s expensive and inefficient to build these power plants just to meet demand in those peak hours. It’s like purchasing a large van that you will only use for the three days a year when your brother and his three kids visit.
The grid requires power supplied right when it is needed, and usage varies considerably throughout the day. When grid-connected batteries help supply enough electricity to meet demand, utilities don’t have to build as many power plants and transmission lines.
Given how long this infrastructure lasts and how rapidly battery costs are dropping, utilities now face new long-term planning challenges.
About half of the new generation capacity built in the U.S. annually since 2014 has come from solar, wind or other renewable sources. Natural gas plants make up the much of the rest but in the future, that industry may need to compete with energy storage for market share.
In practice, we can see how the pace of natural gas-fired power plant construction might slow down in response to this new alternative.
So far, utilities have only installed the equivalent of one or two traditional power plants in grid-scale lithium-ion battery projects, all since 2015. But across California, Texas, the Midwest and New England, these devices are benefiting the overall grid by improving operations and bridging gaps when consumers need more power than usual.
Read full report here.