A week ago, Maxwell Technologies announced they had been “been awarded a $1.39 million contract by the California Energy Commission’s Research and Development program to fund design and integration of an ultracapacitor-based energy storage system with Soitec’s CPV system located on the campus of University of California, San Diego—one of the nation’s greenest universities— and a second commercial scale system at Soitec’s solar power plant in Southern California.” This project was to start immediately and run through November 2015.
I seized upon the opportunity to email Maxwell some questions about the future of energy storage. Shaw Lynds, the senior systems engineer at Maxwell, responded. Note that Mr Lynds says that while small micro-grid solar systems may soon be able to operate without a back-up system, it is still too expensive to develop an adequate energy storage system that would allow the grid to run 100% on solar energy. That is why they are focusing on ironing out “fluctuations of up to 5 minutes.” Yet it would seem almost inevitable that some year, in the not too distant future, solar energy will be able to supply all of our power needs.
Q. To what extent will the technology that you and Soitec are working on compensate for the fluctuations in solar energy?
Our goal is to completely eliminate output fluctuations of less than 30 seconds and provide significant smoothing of fluctuations of up to 5 minutes. The goal of this demonstration is that show that solar can achieve high penetration in the grid without need of large amounts of spinning reserve to keep the grid stable.
Q. Do either solar or wind energy have problems with power surges and does your technology eliminate this problem?
Both of these technologies are vulnerable to power surges, however this is outside the scope of what this project plans to demonstrate.
Q. What part of the work will be done of the UC San Diego campus?
Our partner Soitec currently has a 22kW CPV tracker system located on the UCSD campus that has been running for several years now. Under this project we plan to add 2.5 kWh of ultracapacitor energy storage to that system to demonstrate the large benefits that even a small amount of energy storage can add to a solar installation.
Q. Can you give an a guesstimate of how long it will be before solar energy can be stored for weeks? (Two years? Five years? Ten years?)
5-10 years at minimum before it is economically viable to store energy on these kind of time scales. This is why we are focusing on shorter time scale firming where we believe energy storage can do the most good in the near term.
Q. Can you see a day when, as a result of the development of energy storage technologies, there will be no need for a back-up to solar energy?
For small micro-grid in remote locations, I believe this day is at hand. However for the rest of us who are not willing to pay such a high price for our power, it is still decades away.
Q. Are you presently working on this problem?
Our focus is on helping solar integrate with the rest of the grid as it starts supply a larger power of the power demand, we are still years away from working on 100% solar solutions.
Q. How extensively are Maxwell’s ultracapacitor-based energy storage system used with renewable technologies? (I have read about it being used with wind, solar & EV’s)
Maxwell has made a name for itself providing highly reliable, and long life back up power. Our 16V modules have become an industry standard for backup power for wind turbine pitch control. If you have ever seen a video of what happens when a wind turbine loses pitch control in a wind storm, then you have an idea of just how critical reliable power is in that application.