PV Tracking Applications Gather Momentum

[jpak]

http://www.renewableenergyworld.com/rea/news/article/2009/03/pv-tracking-applications-gather-momentum

Think of solar panels and you're likely to envision them fixed in a single position. But the sun travels from east to west every day -- at least from the perspective of the Earth -- and also moves from north to south as the seasons change. And solar panels make the most electricity when they are positioned 90 degrees from incoming sunlight.

Solar trackers attempt to solve this problem. They follow the sun, so that the panels mounted on them can catch more rays and make more electricity. Companies claim trackers can increase solar arrays' efficiency by up to 40 percent in some regions. So as developers chase higher returns on their solar investments, trackers have been gaining popularity. Paula Mints, a principal analyst at Navigant Consulting, projects that tracking systems will be used in at least 85 percent of commercial installations with more than 1 megawatt (MW) of capacity between 2009 and 2012.

Several companies say they are seeing tracker growth. Miguel de Anquin, vice president of Premier Power, a solar installer in El Dorado Hills, Calif., says that about 70 percent of its ground-mounted commercial projects involve trackers today. That compares to only 20 to 30 percent of a far smaller pool of projects just four years ago, he says. (See image of the solar trackers at the West County Wastewater District implementation in Richmond, CA that were installed by Premier Power, below.)

And in Spain — which overtook Germany as the world's largest solar market last year — tracker projects went from making up an insignificant part of the market in 2006 to perhaps 25 to 30 percent of new projects in 2008, estimates Maria Lahuerta Antoune, international marketing manager for ADES, a Zaragoza, Spain-based tracker manufacturer. (Lead photo, top of page, shows an ADES installation in Spain.).

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[spin]

1. Back in a prior energy crisis...

the one in 1979, a co-worker designed a solar panel dish that tracked the sun. It worked very well if not too well.

[MineralMan]

2. I built a tracking collector back in 1974 to heat a hot tub.

Worked very well, and cost me almost nothing. The design started when I found a 1 rpd gearmotor in a surplus store. I built a crude focusing mirror from a 8' length of sonotube, lined with foil, and focused it on a set of three 1" copper pipes. The sonotube rotated completely around the pipes once every 24 hours. A pump circulated water and was connected to a 24-hour timer that ran the pump from sunrise to sunset.

Total cost was under $50, and it would actually boil water from noon to 2 p.m.

Crude but effective.