The price of producing electricity from solar energy has dropped rapidly in the last several years and nothing is stopping it from dropping even further, an expert recently told the hosts of Energy Evolution, an S&P Global Market Intelligence podcast.

There is still room for reducing the cost of solar, both by improving the physical workings of the technology itself and by reducing the cost of production and deployment of solar photovoltaics, said Greg Nemet, a professor at the University of Wisconsin-Madison who researches technological shifts and how public policy can affect those changes. Once denounced as too expensive, solar energy is already displacing other fuel sources as the cheapest form of generation in some regions.

Nemet, who wrote the recently published book "How Solar Energy Became Cheap," noted one of the challenges with solar energy is that once it is installed it essentially becomes a zero variable cost source of electricity. That could contribute to under investment on the part of utilities. The solution, he said, is to modernize utility regulations that in many cases were created decades ago in order to better accommodate renewable energy resources and other technologies.

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