Exploring Future Applications of Energy Storage

By Kevin Zhu MS '20
Hometown: Shanghai, China
Major: Civil and Environmental Engineering
Intern, California Department of Water Resources

My summer at the Department of Water Resources (DWR) has been exceptionally rewarding as it feels like I'm bombarded with new information almost every single day. Multiple times a week, I meet with advisors, State Water Project stakeholders, contractors, other state agencies, and private businesses. With each new interaction, I gain a different perspective on the current energy market and energy-water nexus in California.

Recently, I joined a lunch meeting with Alex Morris from the California Energy Storage Association (CESA), an advocate for new storage options in California which helps the government with mandating renewable and storage integration for grid decarbonization.

As you might already know, the power grid is a complex system in which electricity supply and demand must always be equal—supply is contantly adjusted to meet the changing demand. Energy storage plays a critical role in the balancing act of creating a more flexible and reliable grid system. During our conversation, Alex mentioned a future transition from fast ramping mitigation storage options to bulk solar shifting. In plain words, we will need higher capacity energy storage facilities that last longer than 4 hours. To achieve the desired results, new technologies, other than lithium-ion batteries, need to be developed for deep cycling capabilities (i.e. using the batteries for an extensive amount of time daily) and better integration with generation facilities.

One of the new areas of storage application I studied combines a battery energy storage system with gas/combine cycle ramp up plants. Taking surplus power from renewables and storing that energy in a battery, that energy is then used for initial startup. This results in an integrated power plant that reacts instantaneously to complement weather-dependent renewable generation.

However, what does this mean to you?

Let’s consider an instance when California’s future renewable power grid suddenly sees an unpredicted loss in production due to an emergency. To prevent brownouts from dwindling electricity supply, grid operators call the battery-equipped ramp up power plant for full output. In less than a second the full supply is on the grid, stabilizing grid power. From the grid’s perspective, full supply is delivered almost instantly rather than waiting for 15 minutes. How amazing is that? Of course, other interesting energy storage applications are being mentioned during the meeting. Such as flywheel with microgrids, thermal storage with CSP, large scale flow battery systems and long-duration gravitational energy storage solutions (e.g. Energy Vault).

Just as you think that you started to know the whole energy sector better, you will be surprised by new pieces of information that you have never heard before. Apart from my regular project, my journey at DWR so far has been a cycle of meetings and trips where I'm exposed to new words, Googling their meanings, and then trying to use the new phrase or acronym in my next conversation.

Read more at the Out West Student Blog »