Energy storage devices store chemical, electric, or thermal energy for later use. Examples include rechargeable batteries (Lead-acid and Lithium-ion), flow batteries, supercapacitors, and flywheels.
Large-scale energy storage systems offer grid services like frequency regulation and electricity price support, often implemented by ISOs or RTOs as a means to balance out their grid while also incorporating renewables.
Long-Duration Storage
Long duration storage holds an enviable place in the cleantech hype cycle. From pumping water back behind hydroelectric dams to lithium-ion batteries at utility scale, long duration energy storage solutions boast a formidable presence in this category of cleantech innovations. Their benefits may include eliminating coal and gas peaker plants while making renewable resources round-the-clock resources and creating a carbon-free grid.
Reality, however, can be more nuanced. While many energy storage technologies can act as LDES, each offers different power-to-energy ratios and discharging times; some like pumped hydro require large canyons and reservoirs; molten salt storage technologies being developed by companies like Highview Power are technology neutral.
Grid planners must identify LDES needs carefully so the appropriate technologies can be developed and deployed accordingly. This will ensure any support mechanism actually delivers the services most required – such as pollution reduction in low-income and communities of color overburdened by fossil fuel peaker plants.
Intermittent Storage
Energy storage solutions (ESSs) provide solutions that balance electricity supply and demand while improving power quality and reliability on multiple timescales – from second-by-second. Solar and wind farms often co-locate ESSs so as to avoid curtailing generation when demand exceeds supply (called dispatchability).
ESSs provide rapid response ancillary services for the electric grid, such as frequency regulation, “spinning” reserve capacity management and load following. They store electricity during peak demand hours before discharging it during off-peak hours in order to help shift energy consumption away from the grid.
These energy storage systems (ESSs) can be placed near intermittent generation sources, behind-the-meter in homes and businesses to promote greater self-consumption of photovoltaic energy, or integrated within microgrids. A variety of technologies exist for achieving this objective – such as pumped hydro and electrochemical batteries as well as regenerative flywheels and compressed air – in order to accomplish their purpose.
Community Resilience
Community resilience has been a focus of significant study across disciplines, particularly engineering and social sciences. As an overarching concept, resilience encompasses a community’s capacity to adapt quickly to changing conditions while being prepared for anticipated hazards or natural disasters and recovering quickly after them.
Physical infrastructure systems play an essential role in community resilience, from built environments and supporting institutions to social media networks and electronic systems. Resilience of these systems can be measured by their ability to regain functionality after a hazard event has taken place.
Communities’ resilience depends on several factors, including preexisting conditions, available resources, and their capacity to adapt quickly in response to hazards events. NIST Building Resilience Program addresses these elements through research, community planning and guidance.
Grid Stability
Reliable electrical power supplies are of vital importance to communities across the world. Aging infrastructure, severe weather events and cybersecurity challenges all compound to make more resilient energy supply necessary.
Solar energy provides a dependable source of power without the need for expensive power plants or transmission lines, helping reduce grid failure risks caused by interruptions to its supply chain. Energy storage devices may help smooth out demand during peak pricing periods to help avoid sudden price spikes for customers.
As renewable energy penetration increases, its effects can place strain on electricity grid stability due to disparate generation and consumption. To address this challenge, energy storage solutions like batteries and pumped hydro storage provide grid balancing services to help balance out generation with consumption while fully integrating renewables. As wind generation peaks, its rotational inertia decreases, prompting grid operators to purchase grid-forming services from inverter-interfaced renewables with inertia-less generators as required by NERC regulations in order to maintain frequency stability – something GE technology allows renewables to do to provide these services while adding value while guaranteeing grid stability.