Trunkneck’s Blog

July 22, 2008

$1 Per watt Around The Corner

Filed under: Science — trunkneck @ 9:13 pm


solar1 $1 Per watt Around The Corner

Achieving grid parity–selling power to the nation’s electric grid at a competitive price–has long been a holy grail of the photovoltaic industry and other suppliers of alternative energy. Yet despite the company’s soaring price share and its multimilliion-dollar order book, First Solar declines to speak to journalists.

In the August issue of IEEE Spectrum, British writer Richard Stevenson combines a journalist’s knack for investigation with the expertise of a solid-state physicist to piece together how First Solar has cracked the problem. He concludes that the secret involves not the photovoltaic cell itself but the way in which it is manufactured. Instead of the familiar silicon, the design uses a compound of cadmium and tellurium. Not long ago it was little more than a laboratory curiosity, largely because nobody had found a practical way to make the cells much larger than a postage stamp. First Solar has now refined the manufacturing procedure to blow up the cells to poster size.

Already the firm has been able to make a profit selling the panels to utilities in a number of countries–particularly Germany–that subsidize alternative energy sources for environmental reasons. Available figures suggest that the manufacturing cost per watt delivered is still too high to compete with that of power delivered on the grid, but First Solar has told investors that it expects to be able to lower the cost substantially. It seems likely that such improvements, together with the rising price of fossil fuels generally, will enable the company to reach grid parity within just a few years. Indeed, the technology is so promising that it puts into question whether there will be enough tellurium available to make all the solar panels the world is likely to demand. Stevenson’s conclusion is that the answer is yes, because increased demand for the panels will stimulate the search for new supplies of the scarce element.

Meanwhile, other photovoltaic technologies continue to advance, not the least of which is silicon. If, as expected, the current shortage of silicon should abate in the coming years, then First Solar’s clear lead on the industry may narrow. In any case, photovoltaic cells seem poised to advance from their current role in niche applications to become one of the more important sources of electricity in the world.

June 28, 2008

Iowa State University’s Latest Solar Car

Filed under: Science, Tech — trunkneck @ 12:50 am

It was going to be another long, hot day in the garage.

The task of the day for Iowa State University’s solar car team was to glue the bottom half of its race car’s carbon fiber shell to the aluminum tubing of the car’s frame. To speed up the drying and curing, Matt Martin and Wade Johanns set up heat lamps.


bigsolarcar Iowa State Universitys Latest Solar Car

Matt Martin takes his place in the driver’s seat of Sol Invictus, Iowa State University’s solar race car. In the back, left to right, are Team PrISUm members Wade Johanns, Sarah Kelly and Michael Steffen.

A long, hot day got even hotter.

But there were no complaints. The members of Team PrISUm are just weeks away from this year’s big race. And they have a $400,000, 1,400-watt solar race car to finish.

So they worked the bottom half of the car’s shell. Then they’d move to the top half. Then on to the brakes, the battery packs, the solar cells. And if all goes well, they’ll make some test runs before the team leaves July 5 for this year’s North American Solar Challenge.

The challenge will take 24 student-designed and student-built solar race cars from Plano, Texas, to Calgary, Alberta, Canada. They’ll make the 2,400-mile run July 13-22, with a checkpoint in Omaha, Neb., July 15-16 and a stage stop in Sioux Falls, S.D., July 16-18. The route between those cities takes the solar cars into western Iowa for a few hours.

Team PrISUm did very well in 2005, the last time the challenge was contested. The Iowa State car made it from Austin, Texas, to Calgary in 71.5 hours. That was good for a third place finish in the challenge’s stock class and 11th overall against cars in the more powerful open class.

This year’s team is feeling good about the latest solar car, a car dubbed “Sol Invictus,” the Unconquered Sun.

“I think we’re going to do this,” said Sarah Kelly, a senior mechanical engineering major from Rochester, Minn., and the team’s project director. “It’s going to be hard for the next week and a half. Everyone knows that.”

Building this year’s race car has been a challenge because organizers changed the car’s specifications in an effort to improve safety. And there have been some delays getting parts and components back from suppliers and fabricators.

“We’re all working really hard,” Kelly said. “Our mechanical team has to keep plugging away. When they finish, the electrical team has a lot to do.”

Johanns, a senior from Mason City who’s majoring in aerospace engineering, said the project has certainly kept him busy.

But that’s OK, he said, because, “I get to play with carbon fiber every day.”

Sol Invictus’ shell is made of the super-light, super-strong composite material.

Yes, he said, working on the solar car has taught him a few lessons in engineering.

He now knows the proper way to lay up carbon fiber. He knows more about how a vehicle’s suspension keeps the tires on the road. He’s applying his interest in motorsports and aerodynamic design to a very hands-on project. He’s also learned how engineers can work together as a team.

And he thinks Iowa State’s team has come up with a car that can compete.

“With the size of the solar array we have, and without a huge increase in weight, I think we’ll do well,” he said.

Matt Martin, a junior from Rochester, Minn., who’s studying aerospace engineering and will be one of the car’s primary drivers, has been working with the team since early in his freshman year.

He’s glad to see the team so close to getting its car on the road.

“It’s exciting,” he said. “It’s fun seeing something like this come together just because there are so many aspects and so many disciplines involved. To see it all coming together is really rewarding.”

And while there’s still work to do, “I’m proud of what we’ve done,” Martin said. “We’ve all learned a lot and we’ve all added to engineering’s knowledge of solar cars. Really, the work has been done. Now we’ll run the cars to see which car wins.”

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