Photovoltaic power plants produce electricity from sunlight  As a result of astonishing recent technological advances, the cost of producing electric power at photovoltaic power plants, allowing for both construction and operating costs, is one-tenth of what it was 20 years ago, whereas the corresponding cost for traditional plants, which burn fossil fuels, has increased
Thus, photovoltaic power plants offer a less expensive approach to meeting demand for electricity than do traditional power plants
The cost of producing electric power at traditional plants has increased over the past 20 years.