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Energy Storage with Bill Capp: Now and Where We Are Going

October 31, 2022 Sarah Masters interviews industry source, Bill Capp, about the current state of energy storage and its future.

The planning process for the 2023 UNC Cleantech Summit is well underway to book keynotes, panelists, and special guests.  As part of the IE Cleantech Corner Initiative, the UNC student group that helps develop content and speakers for this annual event, I had the pleasure of interviewing Bill Capp, who will be moderating and convening the Long-term Duration Storage panel at the event on March 27 – 28, 2023 in Chapel Hill, North Carolina.

Capp is the founder of Grid Storage Consulting (GSC), a company that advises businesses on how to use advanced energy storage pertaining to the grid. Before founding GSC, Capp worked at Beacon Power for 10 years as President and CEO, where he led a team that developed and implemented a technology called flywheel energy storage and interacted with prominent groups in the energy space (grid operators, the Federal Energy Regulatory Commission (FERC), and public service commissions).

In this interview, Capp provides information on the current state of the energy storage sector and recommendations for accelerating the energy transition in the US.

Role of Energy Storage

Many people know what energy storage is, but what is its role in the development and scaling up of renewable energy? Capp answers this by comparing electrical energy to other products. Companies like Amazon can store their products in warehouses, so they don’t need to keep everything in constant balance. Electrical energy from the grid is different; it must be in balance at all times (generation must equal load) or there will be blackouts. Prior to the addition of renewable energy such as wind and solar, the amount of generation was fairly constant and was controllable by the operators of the equipment.  By comparison, wind and solar generation is variable.  Generation from fossil fuels like coal and natural gas are generally slow-changing. However, renewable energy is very different. Wind and solar power have conditions that change constantly- variability that didn’t exist before in the energy portfolio. Capp explains, “It’s the variability that didn’t exist before in the portfolio of generation that’s creating the need for energy storage.” In addition, having backup energy for times where the sun isn’t shining or the wind isn’t blowing is essential to maintain the reliability of the grid that we all depend on.

Storage Options

While lithium ion batteries are dominating the electric vehicle space today, Capp explains that this technology isn’t likely to be a solution for long-term energy storage. Unlike other technologies, lithium ion batteries have both the energy storage component and the conversion into electricity all contained within one system. The problem with this is that increasing the battery system means increasing both components. Ideally, we would keep the size of the conversion component (power) constant while increasing the capacity to store energy. Technologies like pumped hydro and flow batteries do just this, by disconnecting the energy storage from the power element. Pumped storage hydropower (PSH) involves power generated from water moving downhill through a turbine from one reservoir to another. Alternatively, flow batteries contain two tanks of electrolytes that generate electricity when pumped into a reactor.

Energy Portfolio for Renewables

Capp explained that a portfolio of multiple different energy types will be best for reliable generation of energy. Right now he’s working with Storworks Power, a Colorado firm developing thermal energy storage, a method that involves blowing hot air through concrete, storing the thermal energy at up to 600 C and then, when needed, recovering the stored energy in the form of electricity or steam.

Capp also talked about reusing the many fossil fuel plants such as coal that are being shut down around the world at an increasing rate.  These locations have great value if their major negative attribute – the discharge of greenhouse gas emissions – can be avoided.  The opportunity that has been identified is to remove the coal or natural gas boilers creating carbon emissions and replace them with a green heat source such as electricity from wind and solar.

This heat source is used to create steam which is fed into the steam turbine system already installed at the facility.  Recycling the majority of the value of these plants allows for large-scale electrical energy storage at a very low cost compared to batteries.

Also, many of these abandoned coal plants or other assets in our country are in disadvantaged areas, so there are also economic benefits to using combined cycle with old power plants. Capp explains, “what we could do is show up and get rid of all the bad attributes, but keep the good like the jobs and the tax base.”

One of the things GSC is helping businesses consider is combining thermal energy storage in concrete with hydrogen. This hybrid configuration can use hot concrete for say, 20 to 30 hours and then switch to chemical energy storage in the form of hydrogen. This approach allows for energy storage to be limited only to the size of the fuel storage so there is never a time when the storage will run out.

Role of the Public Sector

Capp thinks there are several policy efforts that will help us to achieve decarbonization of the electrical grid. The Biden Administration’s Inflation Reduction Act (IRA) will result in many positive results such as more energy-efficient appliances. For instance, if someone’s furnace breaks down, there are subsidies that would help them install a new, more efficient heat pump. The IRA also has significant subsidies for the deployment of energy storage and renewable energy.

In the absence of markets for energy storage, California and New York have created a market by mandating that Investor-Owned Utilities (IOUs) procure a certain amount of energy they have to put into the grid. This is a great way to create demand for the product, thereby reducing the cost.

Another market innovation is the capacity market, which essentially secures the appropriate amount of energy resources for years in advance. Capp explains, “essentially if you’re a grid service provider … you have to demonstrate to the regulatory authorities that you have enough electricity reserved. You’re not going to run short next summer. And that’s called service by a capacity market. Not every grid operator has that. California does, PJM does, New York does, and Texas doesn’t.” If utilities don’t meet the specified demand, they will have to pay.

There are also numerous obstacles to regulatory aid in the energy transition, one of them being the limited reach of the federal government. Capp explains that FERC (the Federal Energy Regulatory Commission) can only be involved in activity that affects interstate commerce. This is how Texas is able to have its own, unregulated grid called the Electric Reliability Council of Texas (ERCOT).

Where Will the Money Come From?

The public sector is going to have a lot of work to do when it comes to financing energy storage and renewable energy. Capp thinks this will come down either to a carbon tax or setting a date to have zero carbon emissions by. He also mentions loan guarantee programs and green banks as ways to reduce the risk of funding these investments. While there can be a lot of risk associated with investing in this space, Capp points out that there can be very high returns as well: “I mean, look at the early investments in solar power. They’ve done extremely well. I think that’s why money will continue to flow into storage and other renewable industries.”

Advice for the Young

When I asked Bill about his advice for people who want to pursue a career in this space, he had some helpful points. For those first entering industry, he recommends starting with a job at a larger company to get exposed to the structure and business models that are standard in that space, information one might not be able to get at a start-up. After getting a base of experience, Capp suggests moving into a more entrepreneurial role for those who desire it. He closes with some positive advice: “If you have a job you love, it isn’t really a job. You’re doing what you love.”



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About the Author

This article was written by Sarah Masters, a sophomore at UNC-Chapel Hill majoring in Environmental Science and minoring in Public Policy. She is currently an IE Cleantech Corner Initiative intern involved with the planning of the 2023 program. Connect with her on LinkedIn.