Could it be possible to have renewable energy sources powering a large grid system up to 99.9% of the time at costs comparable to energy rates today? A new research report by the University of Delaware and the Delaware Technical Community College demonstrates how this system could exist by 2030. Through a combination of wind power, solar power, and storage in batteries and fuel cells, an almost completely renewable energy grid could be established.
The scientists developed a computer model that considered 28 billion combinations of renewable energy sources and storage mechanisms. Each combination tested historical hourly weather data and electricity demands over a four year period. Using the historical data, the model was able to determine when energy would not be produced by renewable sources, and would tap into storage devices during those periods of time. When energy generation was in excess, the model would first refill storage devices, then use the remaining to replace natural gas usage, and would only waste excess generated energy afterward. A press release from the University of Delaware on the new report discussed one of the several outcomes of the model with co-author Cory Budischak, the instructor in Energy Management Department at Delaware Technical Community College, “’For example, using hydrogen for storage, we can run an electric system that today would meet a need of 72 GW, 99.9 percent of the time, using 17 GW of solar, 68 GW of offshore wind, and 115 GW of inland wind’”.
The model was not only required to maintain demand as needed through renewable energy generation and storage, but was also expected to minimize costs. A discussion of how costs were determined was also included. Costs of each model combination were determined by calculating true cost of electricity without subsidies, elimination of renewable generation subsidies, and inclusion of fossil fuel pollution externalities, costs which are currently paid for by third parties. The scientists determined that 90% of the load hours can be met at prices below today’s electric costs under these conditions.