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Despite all the talk of Solyndra and Chinese solar companies dumping their products onto the US market, the development of projects in the US continues apace. Driven by falling costs for photovoltaics and California's Renewable Portfolio Standard, many utility-scale projects are in the works in the southwest United States. These seven mega projects were culled from Solar Energy Industries Association research on all the major projects completed, under construction, or under development in this country.

Looking over that list, there are two large questions outstanding.

1) Will concentrated solar power projects, which work like normal power plants but substitute solar heat for fossil fuels to generate steam, remain competitive with PV projects? CSP projects will be able to accommodate energy storage easier than PV, but PV costs are falling faster. Keep an eye on that going forward.

2) Will utility-scale projects out in the desert make sense, generally, going forward? Right now, all kinds of models are springing forth for getting solar onto the roofs of individual homes and businesses. While the cost to install the solar panels is lower out in the desert and the solar resource is better, the plants have to compete at wholesale prices. Solar panels on roofs are competing with the retail price of electricity, which is considerably higher.

What's certain is that all of these kinds of projects have powerful backers and so in the near-term, we're likely to see many different experiments trying to find what works best.