Last year, the U.S. energy storage market nearly doubled, and it is expected to double again in 2019. In fact, the final quarter of 2018 broke the previous record for megawatt-hours deployed in a single quarter by 50%, according to a report from Wood Mackenzie Power & Renewables and the Energy Storage Association (ESA).
Although solar-power projects are typically more likely to take advantage of battery storage (projects in Hawaii and Texas make up a significant portion of the afore-mentioned broken record), wind energy also benefits from storage in certain cases. For example, Texas’ largest energy storage site (and seventh largest in the country), which came online at the end of 2018, is co-located with Luminant’s 180-MW Upton 2 Solar Power Plant — but it can make use of solar and grid-generated wind energy.
The 10-MW, 42-MWh lithium-ion storage system captures excess solar energy produced during the day and uses it later in the day when demand is at its highest. However, the system can also take advantage of low-priced grid power, during times of high wind output for example.
Duke Energy’s 153-MW Notrees Wind Farm is another Texas project with battery storage. Constructed in 2012 with battery upgrades in 2016 (lead-acid were replaced with lithium-ion batteries without any performance interruption), it remains the largest wind-integrated battery storage project in North America (for now).
Of course, there are others. BP installed a Tesla-made 212-kilowatt, 840-kilowatt-hour battery storage system at Titan-1 wind farm in South Dakota last year. Portland General Electric recently partnered with NextEra Energy to build the 1,000-plus-megawatt Wheatridge Renewable Energy Facility in Oregon, starting in 2020. It will consist of a 300-MW wind farm, a 30-MW battery storage system, and a 50-MW solar farm.
Last year, the Colorado Public Utilities Commission approved Xcel Energy’s plan to close coal-fired units 1 and 2 at the Comanche Generating Station — 10 years ahead of schedule. The units will be replaced with a $2.5 billion investment in renewables and battery storage, which includes 1,131 MW of wind, 707 MW of solar PV, and 275 MW of battery storage across the state.
A digital map detailing more than 120 lead battery-powered energy storage projects was recently unveiled by the Consortium for Battery Innovation, which provides research and innovation in advanced battery technologies. The Department of Energy’s Global Energy Storage Database also provides free, up-to-date information on grid-connected energy storage projects.
Why the growth in storage?
Much of the growth of energy storage in the U.S. is attributed to less costly batteries and more efficient storage systems. Battery storage prices are falling faster than expected, according to findings from BNEF.
Renewable energy growth is also a factor. New wind and solar projects took an early lead in January 2019 over all other energy sources for generating capacity, with renewables expected to be the fastest growing sources of energy over the next two years. Renewable resources are expected to grow as coal declines. Enter battery storage, which can support the variability of wind and solar power, storing power when winds are strong, or the sun is shining for those high-demand electricity hours.
What’s further facilitating the deployment of battery storage in the U.S. are new policy structures. Last year, multiple states established ambitious storage mandates. A few cases in point: New York announced a 1.5-GW energy storage target by 2025, New Jersey is aiming for 2 GW by 2030, and Arizona expects 3 GW by 2030.
In addition, there’s the outcome of the Federal Energy Regulatory Commission (FERC) recent Orders. FERC Order 841 requires bulk-system operators to establish new rules to integrate storage. Also, Order 845 revises interconnection rules and protocols for generators larger than 20 MW, opening new opportunities for storage.
With dropping battery costs, battery storage systems provide several benefits to the electrical grid, including increased capacity and efficiency of existing generators, flexible demand, frequency regulation, and grid congestion alleviation. This is in addition to supporting the variability of renewables.
Here are some recent developments in the energy storage sector:
EVgo, currently the nation’s largest public electric vehicle (EV) fast-charging network, has contracted for 100% renewable energy to power its customers, becoming the first EV charging network in the U.S. to do so. This means that EVgo is buying a combination of Green-e certified wind and solar energy across the country through its electricity suppliers and REC partners.
NYSERDA, or the New York State Energy Research and Development Authority, released a new Battery Energy Storage System Guidebook to assist local permitting authorities and the storage industry in navigating the siting and review processes for the development of battery storage projects.
ESA recently launched the Energy Storage Industry Corporate Responsibility Initiative, which “signals the intent of all signatories to engage in a good-faith effort to optimize performance, minimize risk and serve as an exemplary corporate citizen in the manufacturing, deployment, implementation, and operation of energy storage projects across the United States.” To date, 30 companies have signed the pledge, emphasizing their commitment to the well-being and safety of consumers.
Stanford University researchers are working with the Department of Energy’s SLAC National Accelerator Laboratory to make batteries safer, charge faster, and store more energy. The team is studying “hotspots” in lithium batteries, which may lead to short-circuits or fires. The aim is to create ways to monitor battery temperature for safer systems.
The DOE announced up to $30 million in funding to support long-duration energy-storage. This means storage systems that can last not just hours, but days. The research teams are expected to develop storage systems that are deployable in almost any location and discharge electricity at a per-cycle cost target much lower than what is currently possible.