Sun, Wind and Storage

By Melissa Schwenk

Weather is not always predictable. Those of us living on the East Coast know this all too well after experiencing both an earthquake and hurricane in the same week in August.Wind

The fact that the wind doesn’t always blow and the sun doesn’t always shine creates a dimension of complexity when balancing load and supply on the electric grid. Wind farms tend to have their lowest output during the time of highest electricity use and their highest output during times of lower electricity use, operating at between 25 percent and 40 percent annual capacity factors. How the industry deals with this reality as larger amounts of solar and wind seek integration into the grid remains to be seen.

AES 1 MW Battery TrailerOne way to address the issue of intermittency is through grid-scale storage. Pumped storage is the most mature large-scale storage technology today, but there are plenty of other storage options on the horizon – batteries, plug-in hybrid vehicles (PHEVs), compressed air and flywheel technology to name a few.

In areas where competitive markets (PDF) exist, we have increased opportunities for demonstration, experimentation and monetization of storage. In the PJM Interconnection market, innovative storage (PDF) concepts are being researched and tested, including some unconventional solutions involving electric school busses, the integration of batteries with solar, and the capture of electricity generated from braking commuter trains for storage in rail- side battery arrays to be reused when the trains accelerate out of the station.

Certainly, storage is not the only solution. It’s through a combination of solutions that the electricity industry will enable greater amounts of renewable resources to be integrated in the most efficient manner and with the least amount of risk.

Information on PJM’s alternative technology pilots is available.

This entry was posted in Uncategorized and tagged , , , , , , , , . Bookmark the permalink.