CPV

Cool Earth Solar eyes rural power with balloons

Cool Earth Solar has one of those radical green-tech ideas that may actually make a real commercial impact.

In the next two weeks, the company plans to start testing a prototype solar plant built around rows of reflective balloons hung on poles. The solar balloons, which are eight feet in diameter, look something like a tube for sledding or laying around the pool, but each one can generate 1 kilowatt of electricity.

It's a design that combines cheap building materials, notably plastics, with expensive high-efficiency solar cells. Light goes through the side of the balloon facing the sun, is … Read more

Competition heats up in concentrating solar firms

There are two approaches to magnifying sunlight to make electricity--either concentrating light to make heat or concentrating light to boost solar cells' production.

Cyrium Technologies on Wednesday said that it has raised $15 million to compete with incumbent concentrating photovoltaic cell manufacturers. The series B round was led by the Quercus Trust.

The company is one of a handful of firms that makes high-end, efficient solar cells. These high-efficiency cells are used in conjunction with mirrors or lenses to boost output of solar arrays.

Commercial versions of these multijunction cells--essentially three cells stacked on top of each other--have an … Read more

With transparent HP tech, pretty solar buildings?

Hewlett-Packard is licensing flat-panel display technology to a start-up that could lead to dramatically more productive--and aesthetically pleasing--solar panels.

The deal, announced Wednesday, allows Livermore, Calif.-based Xtreme Energetics to use HP-developed transparent transistors to bend light in concentrating photovoltaic, or CPV, solar arrays. CPV systems squeeze more electricity from panels by maximizing the light that hits solar cells.

The company is in the process of raising an "imminent" $5 million series A round of venture funding, and it anticipates a series B $35 million round, CEO Colin Williams said.

It intends to have a first-generation solar array … Read more

IBM replants chip-cooling tech in solar farms

IBM has developed technology that will let solar cells withstand the heat of more than a 1,000 suns.

At a technical conference on Thursday, representatives from IBM Research's photovoltaics research will present a method for cooling concentrating photovoltaics, a solar design where light is magnified onto high-performance solar cells.

Heat is a serious issue when it comes to concentrating photovoltaics, or CPV. The efficiency of cells degrades at high heat and can damage, and conceivably destroy, equipment at extremely high temperatures.

IBM said that its liquid-metal cooling technique, adapted from high-powered computers' chips, can remove roughly three-quarters of … Read more