Sunball - the World's First "Solar Appliance"?
Ah, don’t ya just love the enthusiasm of the underdog? Green and Gold Energy of Adelaide, South Australia, sound as though they are poised to take on the heft of, not just the nuclear lobby, but also the solar industry, as well. They believe their SunBall Solar Appliance is the bee knees of domestic energy delivery. Their calculations suggest the Sunball should provide electricity to residences cheaper than current grid pricing. How are they going to manage this feat? Well, the Sunball (a bit smaller than a basketball) uses triple junction solar cells, which are apparently related to the same panels driving the Mars rovers, Opportunity and Spirit. A one square metre of flat panel made from such cells would supposedly cost about $100,000 AUD. So instead the Sunball uses them in 1cm2 configurations, and then places an optical acrylic Fresnel lens above the cell. This captures 500 times more light and focuses it down on the cell. More >A heat spreader connected to the rear aluminium hemisphere effectively diffuses the heat build up. All this is combined with a dual-axis, dawn-to-dusk internal tracker, which follows the sun throughout the day. The assembly is said to have an efficency of >33%, whereas many flat panels are about 15%. Remarkably the cost for a Sunball is expected to only be about $1,600 AUD, when they hopefully go on sale in February 2006 (with export planned for June 2006). May their dreams be realised. ::Sunball via ::The New Inventors
PS: According to figures offered by Green and Gold Energy, even using solar cells with just 10% efficiency, we could cover just 0.16% of the land area on Earth with photovoltaics and supply 20 TW (Terawatts) of power globally. Today we are using about 13 TW.