A study published in the Journal of Power Sources claims that a large electric grid could be powered by renewable sources 99.9% of time and at a comparable to today’s electricity price by year 2030.
The research jointly conducted by scientists at the University of Delaware and Delaware Technical Community College reveals that the demands could be met with a winning combination of wind power, solar power and fuel cells and battery storage. According to Willett Kempton, professor in the School of Marine Science and Policy in UD’s College of Earth, Ocean, and Environment, this argues the common belief that renewable energy is unreliable and expensive.
To calculate the costs and to achieve optimal optimal results, the team developed a computer model that takes into account 28 billion combination of sources and energy storage mechanisms. These were tested using hourly weather and electricity demands data collected in a period of four years. The spatial aspect of the model was based on data from a large regional grid called PJM Interconnection, which covers 13 states, equaling one-fifth of the US electric grid.
The interesting aspect of the study is that the model here does not match generation to electricity use, but instead it focuses on minimizing costs. The key finding is that a very large electric system can be powered by renewable energy.
Cory Budischak, instructor in the Energy Management Department at Delaware Technical Community College and former UD student, who also co-authored the paper states that if hydrogen is used for storage, 72GW can be easily generated by solar, offshore and inland wind.
By expanding the area of renewable generation, having sufficient storage systems, and, if needed, reliable backup gas-burning plants, the team achieved the reliability of their findings. If there was not enough energy produced by the renewable sources, the model took into account the storage, and if both means fail, only then the model considered the fossil fuel. In the opposite case, all extra generated energy was sent to storage, and when the capacity of the storage devices was met, the the energy was let to go to waste.
Within the study, the team estimated future costs without additional subsidies from the government. The results showed that in 2030, the capital costs for wind and solar would be half of today’s prices, while the maintenance remains the same.
The authors are convinced that the targets set by the government to reduce greenhouse emissions by introducing more renewables, will definitely lead to economic savings.