After years of struggling to become cost competitive in mainstream markets, solar power may finally have its day.

According to a new assessment by the Washington, D.C.-based Worldwatch Institute and the Cambridge, Mass.-based Prometheus Institute, the solar industry is poised for a rapid decline in costs that will make it a mainstream power option in the next few years.

Global production of solar photovoltaic (PV) cells grew by 41 percent last year and by 600 percent since the year 2000. Furthermore, gird-connected solar capacity also grew by nearly 50 percent last year to 5,000 megawatts. However, it still only provides less than 1 percent of the world’s electricity.

Growth in the industry has been hampered by the shortage of manufacturing capacity for the material that goes into PV cells, purified polysilicon. However, in the next two years, more than a dozen companies in Europe, China, Japan and the United States are expected to dramatically increase their levels of production.

This increase in polysilicon will bring costs down by more than 40 percent in the next three years. The results will be dramatic.According to Janet Sawin, a senior researcher at Worldwatch who authored the report, “The conventional energy industry will be surprised by how quickly solar PV becomes mainstream.” EC