The Key To Achieving Biden’s Net Zero Goals

n November of last year, the Biden administration launched the “Net Zero World Initiative” which creates alliances with other world governments, philanthropies, think tanks, businesses, and universities to work toward achieving Net Zero emissions within the necessary time frame to avoid the worst impacts of global warming. Biden’s goals for the United States are to slash domestic greenhouse gas emissions by 50 to 52 percent by 2030 and achieve carbon neutrality by 2050, hugely ambitious and entirely necessary goalposts. While the aim is laudable and imperative, what will it take to actually meet these targets?

Renewables are on the rise, and the introduction of much larger volumes of solar and wind power into the United States energy mix is going to require huge advances, particularly when it comes to grid infrastructure and energy storage. Unlike fossil fuels, solar and wind are intermittent, meaning that their production isn’t steady and sometimes defies predictability, as these forms of energy production rely on the weather and the time of day. This means that when energy is produced in surplus throughout the day – when the sun is shining and the wind is blowing – that energy needs to be stored somewhere until demand for energy outstrips supply, reversing the flow of energy to the grid and keeping the lights on.

Further complicating matters for U.S. energy grids, the advent of residential solar power means that many U.S. residents are no longer just energy consumers – they are also energy producers who can sell any solar power they don’t use back to the grid. Before, grids were designed with a one-way flow in mind. When demand went up, we burned more coal, oil, or gas. When it went down, so did production. Now, the operation is much more complicated. Not only can we not control the amount of energy being produced, but we also have an unpredictable excess being returned to the grid.

This in-flow, out-flow creates much more complicated computing for the nation’s aging and fragile energy grids. There is a huge need for more technologically advanced and resilient “smart grids” that can use supercomputing to better predict and regulate these two-way flows. While the Biden administration included provisions to this end in the landmark Infrastructure bill, that budget will barely make a dent in the massive overhaul ultimately needed to support a net-zero nation.

The other thing that the United States will need is energy storage, and lots of it. In fact, a zero-carbon energy future will require a whopping 6TWh of energy storage. The energy storage sector is still in its infancy, but it’s expanding rapidly and is expected to be one of the fastest-growing industries of the next decade. The problem is that at present the industry is largely dependent on lithium-ion battery storage, which can only hold onto energy for a matter of hours and which requires finite, non-renewable materials such as lithium which are going to become increasingly scarce in the future. At present, there is a race to develop new and better energy storage technologies that are long-term, scalable, and environmentally friendly.

The field is full of innovative and emerging technologies, but one, in particular, is predicted to rise to the top. Known as gravity storage or pumped hydro energy storage, this method isn’t actually at the cutting edge at all. It’s been used since the 1920s, and that’s a large part of the appeal. It’s simple, it works, and it’s a proven technology. This method involves pumping water from a reservoir or holding tank at the bottom of a hill to a reservoir at the top of a hill using excess energy during times when renewable power production exceeds demand. The water is held until energy is needed, when it is then released to flow through turbines with the aid of gravity, spinning turbines to create energy along the way.

There is already a lot of installed pumped hydro storage around the world – in fact this method dominates the current field of energy storage by capacity. But some of these projects have been highly controversial, as they sometimes involve damming rivers, which can be ecologically devastating. The best thing about pumped hydro storage, however, is that proximity to a river is totally unnecessary. Closed-loop reservoir systems can and should be an efficient and environmentally friendly fix to the energy variability problem.

By Haley Zaremba for