To save the world, America needs to solve energy storage
ZEGA RAS-WORK: President Biden plans to aggressively tackle climate change, mainly by electrifying the American economy. An integral part of this initiative’s success will be whether or not the United States implements grid-scale energy storage, conclusively solving one of green energy’s greatest challenges––the intermittency of wind and solar.
After successfully passing and implementing the American Rescue Plan, Joe Biden and congressional Democrats must decide on their next legislative priority. The White House has previously touted a climate-focused infrastructure bill. Separately, Senate Majority Leader Chuck Schumer (D-NY) has proposed legislation to increase U.S. competitiveness against China, including boosting domestic innovation and research spending, among other measures. Whatever the next major spending bill ends up being, the U.S. needs to invest in cheap, scalable energy storage for the grid. Not only could this expedite America’s clean energy transition, but it could help expand renewable energy adoption globally.
Energy sources like solar and wind are intermittent by nature, producing excessive amounts of energy at peak times or low amounts at suboptimal times, depending on seasonal or daily cyclical changes. This differs from fossil fuels, which supply a constant output called “baseload” energy. In extreme weather events, this intermittency can become a serious liability. For example, California’s massive heat wave last summer compromised multiple natural gas power plants, cutting off baseload energy and slow winds meant that wind power output was low, resulting in blackouts. In order for renewables to fully replace fossil fuels, they require massive energy storage at the scale of grid infrastructure.
The concept of energy storage isn’t new; pumped storage, using electricity to pump water into an elevated reservoir and releasing it to generate hydroelectricity, has been practiced for over a century. However, for various reasons, some believe pumped storage is becoming obsolete for global use, particularly with challenges like water scarcity and scalability. Alternatively, one of the most inexpensive energy storage technologies is the lithium-ion battery (Li-ion), a Nobel prize-winning invention already being put to use to complement renewables. In 2017, Australia commissioned the world’s largest grid-linked energy storage system based on Li-ion technology called the Hornsdale Power Reserve (HPR) in South Australia. So far, HPR’s main purpose has been to make the South Australia grid more resilient with its fast frequency response capabilities―its ability to quickly discharge energy to regulate grid frequencies when they deviate from a normal alternating current frequency range.
Battery storage has been advancing quickly. Over the last decade, the price of storage batteries decreased by 90 percent, down to $137 per kilowatt-hour (kWh) of energy in 2020, due to increases in battery energy density from extensive R&D and economies of scale from mass production. This was only made possible by the high-risk, long-term research and development investments of the Advanced Research Projects Agency-Energy (ARPA-E), under the U.S. Department of Energy (DOE), creating new markets like electric vehicles, storage and grid services. With markets and policies transitioning toward sustainability, it is projected that global demand for Li-on batteries for energy storage will grow from 7 gigawatt hours (GWh) in 2019 to 457 GWh in 2030. Coupled with the falling costs of solar and wind technology, not only will battery storage grow in the U.S., but developing nations will soon adopt renewables out of self-interest, which has already begun to occur.
However, while Li-ion batteries are revolutionary, they face serious challenges. There are considerable environmental justice issues in battery production. Lithium extraction involves drilling holes in the salt flats of South America and pumping out a mixture of water and minerals, which evaporates and is filtered for lithium carbonate. The process requires 500,000 gallons of water per ton of lithium, and once used up 65 percent of the water supply in Salar de Atacama, Chile. It has also contaminated soil and potable water streams, harming residents of Argentina and Chile living in proximity to lithium mines. Indeed, competing international interests in Bolivia’s lithium reserves threaten its sovereignty over natural resources within its borders.
Additionally, while we’re beginning to develop Li-ion batteries without cobalt, it is still a key component of commercial batteries today. Approximately 60 percent of the world’s cobalt comes from mines in the Congo, fuelled by exploitative working conditions and child labor. In Southern Congo, cobalt mining has also released uranium deposits, causing a spike in radioactivity levels in mining regions, polluting rivers and drinking water and exposing unprotected workers to raw cobalt, uniquely toxic in its metal ore form.
Furthermore, from a performance perspective, the ultimate test for any grid storage technology is its load-shifting ability: whether it can charge when renewables are providing power and discharge power when they are not. In other words, this is how surplus energy from peak times is saved to be used during suboptimal times, to stabilize the grid’s energy supply. While they are currently the best option we have, Li-ions aren’t optimized for grid-scale storage. Because lithium is the lightest metal element, has favorable electrochemical properties and has high energy density for its mass, Li-ion batteries are designed for portable electronics like smartphones and laptops and electric vehicles, rather than stationary storage. Li-ions must be able to store energy for extended periods.
However, this requirement exposes one of batteries’ weaknesses: degradation. Li-ion batteries degrade because of internal chemical reactions that diminish their ability to hold a charge over time. This would be accelerated by the strain of loading and unloading a battery storage system to stabilize a grid. Researchers are trying to address this with materials that can replace lithium, such as sodium, which some experiments have shown to be very durable in batteries. Sodium-ion batteries are also less costly and less ecologically damaging to produce, due to sodium’s high natural abundance in the oceans. Scientists are also creating storage batteries that operate on entirely different chemistries such as liquid metal batteries and vanadium batteries. While some of these prototypes show better load-shifting capabilities and higher cost-savings, these technologies are in early stages and will take time to become marketable products that can be mass manufactured at a price competitive with that of lithium-ions, which continues to fall.
These challenges require Congress’ funding; the next bill must include R&D funding for energy storage technology. There are still great improvements we can make in conventional lithium batteries to make them more effective and cheaper. This requires funding, risk-taking and patience. The U.S. government, through public institutions like ARPA-E, is the only entity that can afford to invest in these high-risk technologies, the dividends of which we won’t reap for decades; it was the federal government that invested in new drilling technology in the 1970s that led to the shale gas revolution of the 2000s; in 2009, the DOE granted a $465 million loan to a risky electric car manufacturing startup called Tesla, now a pioneering company in energy storage and electric vehicles. The next breakthrough in storage will be publicly funded, and yet Congress has been shy to meet the moment. The DOE is severely underfunded, with federal energy R&D funding falling from $10.5 billion in 1978 (inflation-adjusted) to $8 billion in 2020. If federal research investment was at the same share of GDP as in 1978, today’s annual DOE research budget would be $32 billion. Under the Trump administration, ARPA-E was largely sidelined and almost abolished.
With the U.S. projected to only contribute 5 percent of global cumulative emissions over this century, and 95 percent coming from developing countries in Asia and Africa, the biggest policy impact it can have on global emissions reductions is to make decarbonization cheaper, which energy storage is central to. It is no different to how American R&D led to massive cost reductions in solar photovoltaics, promoting the adoption of solar energy across the world.
Ultimately, cheap, scalable and environmentally sustainable energy storage will be a key component to scaling renewables up, not just in America, but around the world. The seriousness of climate change requires Mr. Biden and Congress to support America’s science institutions in reaching their innovative potential to accomplish this daunting but important breakthrough.
Zega Ras-Work is a writer interested in renewable energy, economic development and agriculture. He is a sophomore studying political economy and environmental studies in the College.