long duration

The wind and the sun are inexhaustible sources of energy, and we are tapping into them to produce electricity at a growing rate around the world. But neither of them is always available when we need them. When the sun isn’t shining and the wind isn’t blowing, they don’t work.

An opposite problem also exists. When our energy needs are low, but it is sunny or windy, solar and wind power are all dressed up with nowhere to go. Energy storage is the answer to both of these problems. When there is excess generation, store the energy for later use. When there is need for energy and not enough is being generated, tap into the energy that is stored.

Giant banks of lithium-ion batteries are the rapidly growing form of energy storage, and they are increasingly providing resilience in the electric grid. But battery storage is short-term energy storage. Even the largest battery banks can only provide a few hours of electricity.

So, there is a real need for “long-duration energy storage” – systems that provide at least 10 hours of backup power and sometimes much more – for the grid to be fully reliable.

Pumped hydro storage, which uses water from elevated reservoirs to drive turbines, has been around for a long time. Historically, this is the largest form of energy storage in the world. Other methods include pumping compressed air into underground caverns or lifting massive blocks into elevated positions. All of these techniques use excess electricity to place things like water, air, or cement into a position where they can be used to drive electrical generators.

The grid of tomorrow will store energy in giant battery banks, but also in the ground, in reservoirs, and in large structures.

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How giant ‘batteries’ in the Earth could slash your electricity bills

Photo, posted March 21, 2024, courtesy of Sandra Uecker/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

There are some people who worry that an electric grid heavily dependent upon intermittent sources like solar and wind power may be more susceptible to blackouts. According to a new study by Stanford University, these fears are misplaced.

The study, published in the journal Renewable Energy, found that an energy system running on wind, water, and solar, when combined with energy storage, avoids blackouts, and lowers energy requirements and consumer costs. In addition, implementing such a system would create millions of jobs, improve people’s health, and reduce land requirements.

The study focused on the stability in all U.S. grid regions as well as individual states based on the requirement that all electricity is provided by clean and renewable sources. No fossil fuel use, bioenergy, blue hydrogen, or even nuclear power were included in the modeling. Critics of such a shift in the energy system point to grid blackouts during extreme weather events in California in 2020 and Texas in 2021 as evidence that renewable sources can’t be trusted. But in both cases, renewable energy was not found to be any more vulnerable than other sources.

The study looked at the costs of the transition – which would be substantial – but found that it would pay for itself fairly quickly based on energy cost savings alone.

A significant finding of the study was that long-duration batteries were neither necessary nor helpful for grid stability. That stability could be obtained by linking together currently available short-duration batteries. Interconnecting larger and larger geographic regions would make the power system smoother and more reliable. Overall, intelligent management of the electric grid can result in a reliable and clean power system.

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Stanford researchers point the way to avoiding blackouts with clean, renewable energy

Photo, posted October 17, 2016, courtesy of B Sarangi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Giant batteries in the Earth

The wind and the sun are inexhaustible sources of energy, and we are tapping into them to produce electricity at a growing rate around the world. But neither of them is always available when we need them. When the sun isn’t shining and the wind isn’t blowing, they don’t work.

Web Links

Avoiding Blackouts With Renewable Energy | Earth Wise

There are some people who worry that an electric grid heavily dependent upon intermittent sources like solar and wind power may be more susceptible to blackouts. According to a new study by Stanford University, these fears are misplaced.

Web Links