23 Oct Battery Storage: Coming to Your Neighborhood Soon

According to energy industry expert, Michael Quinn, VP and CTO of Oncor, battery energy storage systems are in our near future. At a recent Symposium on Energy and the Environment here in Austin, he shared the benefits of and some current pilot projects with battery storage.

Why Have Energy Storage Systems? – As our energy resources diversify into renewables like wind and solar, energy storage systems offer many benefits to electric grid operations and home-owners alike. Benefits include maintaining reliable power supply, decreasing operating costs and increasing efficiency. The variability of wind and solar generation resources will make energy storage systems a real asset to our electric grid. Storage technologies will allow electric grid managers to make electricity stored from these variable resources available during those times when it is most needed – in Texas, on hot summer afternoons from about 4:00 to 7:00 pm. Energy storage will also help to avoid power outages and brown-outs. Storing electrical energy allows the electric grid to maintain its reliability and security while keeping down costs by avoiding the need for additional centralized generation capacity like natural gas power plants. Also, the current Texas electric grid is very inefficient in the use of its generation capacity, because about 60% of that capacity sits idle at night. Storage systems will increase the efficient use of our generation resources by capturing more renewably generated electricity for later use.

Oncor Pilot Projects – Right now, it looks like battery storage will come first to the neighborhood and office park before individual homes in general. Oncor's current pilot projects are testing the use of lithium batteries for electricity storage for those two scenarios.

1. NSRI (Neighborhood Storage Reliability Initiative): Oncor has deployed five neighborhood power backup systems in the Dallas/Fort Worth area so far. These systems can supply electricity during outages for about two hours. Each installation has a 25-kW lithium ion battery bank with electronic power control system.

2. Microgrid at Oncor’s new Technology Demonstration & Education Center: About 20 minutes south of Dallas, Oncor is nearly finished with this new facility for education and research that can operate as a microgrid separate from the surrounding larger electric grid. It has 101.3 kW of solar PV, 200 kW of lithium ion battery storage and a 65-KW propane generator. The facility will, also, feature a rainwater harvesting system and an urban wetland. The TDEC is scheduled to open after January 1 next year.

What’s Coming Down the Line Soon? –  From his company's research , Mr. Quinn predicts that battery energy storage systems will be an integral part of our electric grid in three to five years. Beyond battery technologies, he sees pumped water and compressed air as potential forms of storage in the more distant future. There are some technical and economic factors to address yet before that happens though.

Part of why energy storage is not a significant asset on the grid yet is that our current electric rate structure makes it challenging to capture all value streams associated with storage. One way to capture more of the value of storage would be time-of-use charges for electricity consumers – both commercial and residential. Time-of-use rate programs are just beginning to emerge. For example, TXU offers their customers free electricity at night when it’s least expensive. It will certainly be interesting to see how the management of our electric grid and our rate structures evolve in the next few exciting years.