Special Section: The Energy Transition: Long-Duration Energy Storage Can Lead the Clean Energy Transition

Emerging long-duration energy storage technologies will be a critical factor in the decarbonization of energy generation.

Countries including the Philippines, India, Chile, Australia, Canada, Spain, and the U.S. have recently pushed forward new policies designed to accelerate the deployment of renewable energy and achieve their decarbonization goals. This global momentum demonstrates the vital role of renewable energy in mitigating climate change, lowering energy costs for consumers and businesses, and bolstering energy security.

While the rapid pace of innovation in renewable energy generation is driving costs lower than traditional fossil-based energy, there is an urgent need to create new economies that can more quickly advance the clean energy transition.

To keep the Earth’s temperature increase within 1.5°C above pre-industrial levels, the International Renewable Energy Agency (IRENA) has forecast that renewables must jump from around 26% of electricity generation today to 90% by 2050, adding 836 GW of renewables capacity per year (1). In short, there is a chasm between today’s renewable energy generation and tomorrow’s needs.

The policy updates being implemented today by national governments are progressive and welcome; however, they do not factor in the integral role that long-duration energy storage (LDES) will play in achieving net-zero carbon emissions. LDES will be critical in ensuring that reliable and sustainable power is available 24/7.

LDES stores excess energy generated during periods of low demand, such as from renewable sources like wind and solar power, for later use when electricity or heat demand is high. This energy may be stored using non-lithium batteries, pumped hydro storage, or thermal energy storage systems.

LDES systems provide flexible services to ensure loads can be met with renewable energy, while also assisting with backup power during blackouts, stabilizing the electrical grid, providing inertia to manage grid frequency, and offering other ancillary services. By storing energy and heat for extended periods of time (in comparison to lithium-ion batteries), LDES reduces the reliance on fossil fuels and accelerates the transition to a cleaner, more sustainable energy future (Figure 1).

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▲Figure 1. Today’s power procurement through renewable power purchase agreements (PPAs) still relies on fossil-based energy during certain hours of the day. During those hours, the carbon emissions generated by fossil-based energy production are greater than the carbon abatement produced by hours of renewable energy overproduction in the middle of the day.

LDES is a solution that can assist the clean energy transition today, as it connects renewable energy at all times to heat and power industries and local communities. If countries are to reach their decarbonization goals, LDES must be deployed at a pace to match the projected growth in renewable energy.

This article explores some of the main forms of LDES currently available, discusses the challenges of scaling LDES technologies, and examines how the Inflation Reduction Act (IRA) will impact the development and deployment of LDES technologies.

The four types of LDES...