Environment

New solar technology tests the waters with promises of cheaper energy

New solar technology tests the waters
New solar technology tests the waters
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Sunengy collector in operating and protected positions.
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Sunengy collector in operating and protected positions.
New solar technology tests the waters
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New solar technology tests the waters
A depiction of an array of LSA collectors in operation
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A depiction of an array of LSA collectors in operation
First prototype produced in 2006
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First prototype produced in 2006

April 23, 2009 A new solar technology is not only taking a fresh approach to capturing the sun’s energy, it is also promising to produce electricity at a comparable cost to fossil fuel generators. The liquid solar array power generator (LSA), made predominantly from plastic, floats on water.

Each LSA panel has a tiny area of silicon photovoltaic cells on the water’s surface with a large rotating plastic focusing-lens above, which tracks the sun. According to the technology’s developers, Sunengy, the water plays an important role in cooling the silicon cells.

The lens can also be submerged when rotated fully to protect it during stormy weather and high winds, in particular. At 2mm thick, the lens may appear flimsy but is robust enough to survive winds of more than 100mph due to its unique method of using water, as part of the structure, to protect it.

The water has another use, too. Coated in a special self-cleaning surface, the lens can be washed of dust or salt simply by dunking it, via its sun-tracking mechanism, into the drink.

More than its novel design, the LSA technology can potentially match the cost of producing fossil fuel. According to Sunengy, the LSA can cut the cost of raw solar electricity in the short term from USD$5/W to USD$1.30/W and, in the longer term, to below US$0.60/W, under ideal conditions (this corresponds to about 3 US cents /kWhr).

Gizmag has recently reported on $1/W solar systems, which is seen as the price parity point with fossil fuel-based energy. The LSA, if it is successful, improves on this and would give the argument for using solar energy a significant boost.

The cost of the thin plastic sheet is also extremely low, particularly when compared to the silicon and glass panels used in conventional photovoltaic systems. In addition, the LSA system tracks the sun with high efficiency cells, generating more uniform power than conventional flat PV systems across the day.

Sunengy has produced a proof-of-concept working model and 3D computer design. The company estimates the system should achieve a return on investment within 15 months, helped by the fact that all the major specialized components are available off the shelf. Sunengy believes commercial sales could begin in one to three years.

Sunengy believes the system is suited to large-scale distributed electricity generation on the coast, reservoirs or lakes within 40 degrees of the equator – in fact, anywhere really where there’s good sun, plenty of water and not too many surfers.

Paul Best

6 comments
gormanwvzb
While I think this is a great advance, I would like to know if the focused solar energy creates thermal pollution impacting the sea life. Additionally, are we likely to see a "Not in My Backyard" backlash from expensive, water-front property owners? Hats off to the innovators. I read an article titled, "Is Solar just Blowing Sunshine" at http://economicefficiency.blogspot.com/2008/06/is-solar-just-blowing-sunshine.html. This article would be a good topic for discussion as the key point was cost per kw hour.
Nicolas Wan Chai
How is it anchored? Not all lake beds are of identical depth and ideal topography. While the top part including fresnel lens and pv cell might be affordable, the installation costs could be high. Would a heat-driven Stirling fan be another solution to cool the cell, to eliminate need for water?
Michael Mantion
Thermal Pollution.. Man you don't sound too bright. That said, the solar enegry is focused to a smaller cheaper solar cell. It is not creating sunlight.. as we all know the ocean unlike icecap absorbs most of the sun's energy. It is possible that the water would be cooler because 10-20% of the sun's energy would be removed as electricity. As for the anchored question I am guessing they would put this in an array where they are anchored together. If they used a diagonal/triangle pattern, a large array would be fairly rigid. You would really only need to anchor some key stress areas. As for eliminating the need for water, they have above ground lens/reflector that use air, water, ammonia and a dozen other techniques to dissipate heat. The genius of this design is the simplicity. The simplicity reduces cost and makes the product more robust.
jbenjam
Re: Thermal Pollution: Michael Mantion, you're the one who isn't thinking "brightly". Yes, you're right that the ocean absorbs vast amounts of solar energy, however, it doesn't do it in the first few centimeters of ocean depth! These devices would be warming the surface layer, which is a different prospect from natural solar absorption. The ocean tends to be strongly stratified due primarily to temperature and salinity. Many lifeforms rely on the uppermost layers of the oceans for their habitats, that's where there's the most direct sunlight and nutrients. So, naturally, and change in the temperature environment of these upper layers (i.e., thermal pollution) could have a significant impact on sea life, particularly coastal sea life -- which is where these are likely to be installed.
windykites
Let\'s not get carried away. These gadgets are not going to be deployed in their millions. The heating effect would be minimal. The design looks more suitable for a calm duckpond. It wouldn\'t last 5 minutes in the sea. How would it be stabilised? I can imagine beaches littered with piles of wrecked units, after a storm. It seems the only reason to be on water is to cool the solar cell. There must be a better way.
imagine12braden
How much would one of these cost to produce? Would it amount to anyhing less then what were using now?