Available Solution: Overcoming the Adhesive Challenge in Renewable Energy Storage
California customers could potentially face a threefold increase in utility bills without interventions to address the challenge of storing renewable energy for long periods, according to Gabe Murtaugh, director of markets and technology at the nonprofit Long Duration Energy Storage Council.
In the pursuit of a sustainable future, various technologies are emerging as cost-effective, long-duration energy storage (LDES) solutions. These technologies, including iron-air batteries, CO2-based batteries, flow batteries, and thermal storage systems, are crucial for integrating renewable energy at grid scale, supporting clean energy transitions by storing energy for periods from 10 hours to days or weeks.
Iron-air batteries, such as those developed by Form Energy, harness the energy released when iron reacts with air and water to form iron hydroxide. This technology, seen as a potential low-cost, environmentally friendly alternative to lithium-ion batteries, offers multi-day storage, making it suitable for backup and long-duration applications. However, recyclability challenges persist.
CO2-based batteries, like Energy Dome’s technology, use compressed CO2 cycles to store and release energy for 8 to 24 hours or longer. This system, which reportedly has a lifespan exceeding 30 years, avoids rare critical minerals and has scalable deployment potential with standard components, enhancing cost-effectiveness.
Flow batteries, including variations like iron flow batteries, offer scalability and long cycle life, making them attractive for stationary storage with durations over 10 hours.
Thermal energy storage approaches, such as sensible heat storage in materials like sand or underground pumped water geothermal systems, provide innovative, long-duration storage options often with low operational costs and potential for seasonal storage.
Lithium-ion batteries still dominate shorter-duration grid balancing but are limited to roughly 4 hours of discharge, making them less suitable for deep renewable integration requiring multi-day storage.
Governments and the US Department of Energy advocate for storage solutions that can reliably provide electricity for at least 10 hours, aiming to support grids with high shares of renewables and address seasonal variations.
For longer-duration storage over weeks, many experts put their bets on hydrogen gas. Hydrogen exists naturally in the atmosphere but can also be produced using electricity to split water into oxygen and hydrogen. Hydrogen storage would be used only for Dunkelflauten periods, when solar and wind production is low.
In Germany, renewable energy produced more than 70 percent of the electricity generated in July 2023, while in the US, solar and wind combined contribute 40 percent of overall energy generation. However, on other days, renewable energy generation can fall to less than 30 percent of the nation's total, posing a challenge to avoid blackouts without turning to fossil fuels.
Seth Mullendore, president of the Vermont-based nonprofit Clean Energy Group, suggests reducing the need for storage by charging electric cars at midday when the Sun is blazing and adjusting building heating and cooling so the bulk would happen during windy periods.
Future prospects include scaling these technologies through innovations in materials, digital controls, and manufacturing, targeting rapid deployment, environmental sustainability, and cost reductions to enable widespread adoption from residential to large grid applications.
Both Germany and the US have goals of becoming 100 percent clean-energy-powered by 2035. Achieving this goal will require significant advancements in long-duration energy storage technologies, ensuring a sustainable and reliable energy future.
In the quest for a 100% clean-energy future, innovative technologies like iron-air batteries, CO2-based batteries, flow batteries, thermal energy storage, and hydrogen gas are key for long-duration energy storage (LDES) within the renewable-energy industry, especially in finance and technology sectors. For instance, CO2-based batteries could offer an extended lifespan, while iron-air batteries may present a low-cost, environmentally friendly solution for multi-day storage.
