Energy storage captures energy in chemical, kinetic and thermal forms and converts it back to electricity when required – providing grid services currently met by fossil fuel peaker plants such as rapid response to sudden increases in electricity demand.
Rechargeable batteries such as lead-acid or lithium-ion cells and flywheels are popular examples of energy storage solutions, using electricity to charge them up before discharging energy for profit generation by their owners.
Renewable Energy
As renewable sources like wind and solar become an ever more integral part of our electricity system, their intermittent nature makes energy storage vital. Energy storage helps absorb surplus generation as well as manage seasonal consumer demand peaks – providing grid flexibility during times of change.
Numerous energy storage systems are being developed today. Most use physics as their basis, taking potential energy from sources and turning it into physical work such as lifting or spinning something physical. Companies are banking heat in molten salt, volcanic rocks or batteries powered by renewable chemical processes for future use.
Energy storage acts both as a generator and load, making it a crucial element in improving grid efficiency by decreasing transmission congestion and increasing electricity availability during times of high demand. Furthermore, energy storage reduces dependence on fossil fuels that contribute to climate change while mitigating outages that disrupt critical services or cause loss of food or medicines.
Urban and Rural Communities
Community members and planners are asking: “How can our communities use battery energy storage to support renewable energy?” PNNL has released a report that answers this question by outlining resources necessary for developing, operating and managing community-level energy storage facilities (known as front-of-the-meter facilities) which provide electricity and heat.
Homes and businesses connected to weak grid connections could benefit from installing battery systems to store energy for days or weeks in case of an outage, particularly for solar panel homes and businesses with solar panels. Energy storage solutions also replace dirty fossil fuel peaker plants used during times of high demand – reducing emissions while simultaneously improving public health impacts in urban centers with low incomes or marginalized communities.
Electricity Grid
Energy storage provides flexibility to the electricity grid by responding quickly to fluctuations in electricity demand on sub-hourly timescales (from minutes down to fractions of seconds), as well as frequency and voltage regulation. Storage systems like batteries, flywheels, super capacitors, pumped-storage hydropower can be deployed anywhere along the grid’s pathway from transmission lines through distribution networks until behind the meter in households, commercial buildings or industries – providing instantaneous electricity at any point on demand.
Community solar and aggregated home and commercial rooftop solar projects with storage capabilities are increasingly acting as energy storage at the grid level, providing energy security during hot or cold periods as well as responding to extreme weather events that have become increasingly frequent and severe with climate change. At the grid level, storage helps reduce peak power consumption while simultaneously supporting bidirectional power flow between intermittent renewable supplies; further increasing efficiency by deferring investment in generation and transmission infrastructure.
Energy Efficiency
Energy efficiency refers to the practice of providing similar or better services while using less energy, typically through technology which requires less power for its intended function – for instance an efficient light bulb or ductless air-conditioning heat pump which uses half as much electricity.
Energy conversion requires some loss, with improved energy efficiency achieved when technologies and designs utilize methods which lose less of this initial energy during conversions.
USAID’s Energy Efficiency programs aim to reduce demand and cost for energy services by providing low-cost yet high-performing technologies to households and businesses alike. These designs include lighting, appliances, building insulation materials and vehicles – helping increase disposable income while decreasing energy bills, emissions and waste production.
Energy efficiency programs tend to be more cost effective than investing in new power generation. Unfortunately, market forces sometimes fail to achieve optimal energy efficiency due to an “energy efficiency gap.”