A bright future for solar power

When it comes to solar these days, it's go big or go home.

Utilities are being pushed to use more renewable energy, heating up the business of large-scale solar power. (Click here for related photo gallery.)

There are competing designs for utility-scale solar farms. By concentrating light to make steam, some designs use heat to generate electricity. In parallel, other companies concentrate light onto photovoltaic cells to generate electricity.

The latter, known as concentrating photovoltaic (CPV) systems, may make more sense in a broader set of geographies, compared with concentrating solar thermal. Both forms of concentrating solar power are meant to improve on sun-tracking flat panels.

Which technological approach will win out isn't clear yet, but the demand for centralized solar-power generation systems is there.

Prometheus Institute forecasts that 50 gigawatts of electricity could be generated this way by 2020. Currently, there 430 megawatts worth of concentrating solar power systems installed around the world, according to Emerging Energy Research.

California and Spain are the biggest markets for these concentrating solar power systems. If renewable portfolio standards get passed in more states, we could see a much greater diversity of technologies beyond the solar trough and solar tower.

The Prometheus Institute forecasts that concentrating photovoltaic technologies will be used in midsize to large power plants that range from about 1 megawatt of production to about 100 megawatts.

Concentrating solar thermal systems, meanwhile, will dominate very large centralized power generation.