Cool Earth Solar generates power with 'solar balloons'

Cool Earth Solar on Thursday said it has raised at least $21 million to further develop a solar generator that you could mistake for a shiny kiddie pool.

The Livermore, Calif.-based company said the Series A round, from undisclosed investors, could be augmented by other investors in 60 days.

A ballon that makes electricty.

(Credit: Cool Earth Solar)

Cool Earth Solar has taken a radical approach to building a solar-power plant using a technique called concentrated solar photovoltaics, in which light is magnified onto solar cells to maximize electricity output.

It plans to manufacture plastic balloons, which will be suspended on metal and wire structures. These round balloons reflect light onto a solar cell to generate electricity.

Because its design uses relatively cheap and readily available components, these solar concentrators can generate electricity at a cost comparable to that of natural-gas plants. The inflated solar collectors can withstand 100 mile-per-hour wind.

The plastic solar collectors are mounted.

(Credit: Cool Earth Solar)

The setup can also be unfurled globally, rather than only in places with available funding for expensive energy projects. The company said it is negotiating with utilities to sell electricity from its solar farms. From the company's release:

Our goal from the very start was to find a clean-energy generation solution that could address the global scale of the carbon problem. We discarded everything that couldn't scale, relied on rare components, or had some other critical bottleneck. Ultimately, we developed a novel technology which radically reduces the amount of material in our system and balances labor and capital costs.

Although most people envision rooftop panels when they think of solar electricity, many new solar technologies are being developed for power plants.

Utilities in some states, notably California, need to comply with renewable-energy mandates. And certain regions, such as the Southwest U.S. desert and parts of Spain, are well-suited for solar-thermal power plants.

Concentrating solar photovoltaic arrays are also being tried for industrial-scale solar power, but unlike Cool Earth Solar's, these use sophisticated mounting systems that track the sun and expensive solar cells.