A paper recently published in the peer-reviewed Journal of Power Sources by a team led by researcher Cory Budischak of the University of Delaware Department of Electrical and Computer Engineering predicts that current wind and photovoltaic power will be able to economically meet a grid’s power requirements 99.9% of the time by 2030 using existing technologies.
The team built a computer model of one fifth of the US power grid and analyzed 28 billion combinations of on-shore wind, off-shore wind, and photovoltaic power with electrochemical storage batteries using four years of actual load and weather data. They found that the least cost renewable infrastructures would seemingly yield excessive generation capacity—at times, almost three times the electricity needed to meet electrical load. One of the main reasons that renewables work in this way is that by diversifying generation locations there will be generation in one area even when generation in another is at a low ebb. 99.9% of hours of load can be met by renewables with only 9 to 72 hours of battery storage capacity. The researchers predict that, at 2030 technology costs, 90% of load hours can be met with power costing less than it does today. They suggest that excess power can be used to displace natural gas consumption.
An abstract and the full paper can be found at http://www.sciencedirect.com/science/article/pii/S0378775312014759#