Solar power on track to be world's largest electricity source by 2050

The report, from the Office of Energy Efficiency and Renewable Energy under the U.S. Department of Energy, predicts that rooftop solar panel installations will grow from 0.2% market penetration today to 10% by 2022.

Using that scenario, the analysis found that shareholder earnings fell by 8% for the Southwest utility and by 15% for the Northeast utility using the 10% photovoltaic (PV) rooftop panel market penetration assumption. However, earnings fell by as much as 13% and 41%, respectively, under certain other conditions.

New solar technologies hold promise

Several technologies are poised to improve the efficiency of photovoltaic cells, the technology that turns the sun's rays into electricity. Currently, silicon-based PVs have an efficiency rating of about 20%, meaning 80% of the solar radiation that hits a rooftop panel is lost.

MIT, meanwhile, published a report on a new a material that could be ideal for converting solar energy into heat by tuning the material's spectrum of absorption just right.