We often hear about massive solar farms to produce electricity in the middle of deserts. However, most people must wonder what would happen if all houses featured solar panels on their rooftops to generate electricity. So has the Imperial College London and other universities. They discovered that we could be generating 27 PWh (petawatt-hour) per year, more than the global energy consumption back in 2018.
The study was published in Nature Communications and the Imperial College London had the assistance of three other institutions: Ahmedabad University in India, Columbia University, and University College Cork (UCC) in Ireland. It mapped 130 million square kilometers of global land surface and found 0.2 million square kilometers of rooftop area. The goal was to see the most suitable rooftops to generate electric energy with solar panels.
According to the study, the best places to have such panels are in India and China. In the former, this energy could cost as low as $66 per MWh, while costs in the latter would be just a little more expensive: $68 per MWh. The least affordable places to have rooftop solar panels are the United Kingdom ($251 per MWh) and the U.S. ($238 per MWh).
The primary issue with electricity generated by solar panels is that it is produced primarily when consumption is lower. If there’s no method to store this energy, it is simply lost. The study has not included the costs for storage and said that the potential of energy generation depends “on the development and cost of solutions to store the generated energy.”
Energy-generation costs vary a lot. They can go from as low as $20 MWh for hydropower to more than $170 per MWh with thermal power plants that run on natural gas. Storage alone can have a cost of more than $180 per MWh.
In other words, solar generation with the help of rooftop solar panels needs to offer home and business owners a compelling case for them to invest in the solution. As the researchers from the Imperial College London and their peers stated, governments should try to incentivize this due to the critical role it can have in curbing carbon emissions.