Soliant Energy, a solar-concentrating startup, has switched its, well, concentration.

The company, previously known as Practical Instruments, had been developing a low-concentration technology called Heliotube that tracks the sun and uses lenses to concentrate sunlight into a silicon-based cell. The company claimed the technology, targeted at commercial rooftops, would allow it to use a cell 10 times smaller than what would normally be needed to collect the same amount of sunlight.

Soliant already had received some attention for its Heliotubes. In October, the company raised $8 million in a Series-A round of funding from RockPort Capital Partners, Nth Power, Trinity Ventures and Rincon Venture Partners. And in February, Practical Instruments announced that three California installers had signed on to resell and install its panels, which were scheduled to come out by the end of this year.

But now, the plan is off. The company told Greentech Media on Wednesday it is making its Heliotube technology available for licensing, but is now focused on developing a high-concentration product instead.

"As a startup, we looked at our funding and our resources and decided that we couldn't do both," said Kelly Flores, director of marketing at Soliant. "We've got to be practical. We have to do one or another. And we decided to focus all our energy on high-concentration - a high-efficiency, high-powered panel - so we can get the most power that we can get out of a rooftop."

While the low-concentration Heliotube was meant to replace the regular solar panels seen on most roofs today, high-efficiency products like those from SunPower and Sanyo earn a premium, she said. The new high-concentration product would compete with those, making it also eligible for a premium price.

Yet the product could potentially reduce costs to grid parity, to less than 10 cents per kilowatt-hour, when it comes out in late 2009, Flores said. And the high-concentration approach will reduce installation costs because fewer panels will be needed to generate the same amount of electricity, she said.

The decision came after Soliant snagged up to $4 million from the U.S. Department of Energy in March. In the course of the project focused on high-concentration technology, Soliant partnered with Spectrolab, which makes solar cells made of gallium arsenide.

With these high-efficiency cells, Soliant says it can make a product that is much more efficient, concentrating sunlight into a cell 500 times smaller than the area from which the cell would be collecting sunlight.

Energy Options, PermaCity Corp. and Advanced Solar Electric, which signed on to install the Heliotubes in February, could not immediately be reached for comment.

Eric Wesoff, a senior analyst at Greentech Media, called the decision an example of "the usual flailing" you can expect from startups, but also said it makes sense.

"They voted against low-concentration as not as economically viable as high-concentration, and you might argue that doesn't bode well for the spate of low-concentration systems out there," he said. "I have a feeling that high-concentration can work out in dollars per watt, while low-concentration typically makes no instinctual sense and makes me roll my eyes."

Adding a number of extra steps to the manufacturing process - not to mention the labor, and materials such as plastic, lenses and glass and metal bending - in order to get rid of half the silicon "doesn't make sense" considering the shortage of solar-grade silicon is a temporary issue, he said. "It's not smart."

What does the decision say about the future of other low-concentration approaches out there?

Well, Solaria answered the question by saying it's not like other low-concentrator companies anyway. Instead of taking wafers and using fewer of them to make a cell, it is using an already-finished cell and making two cells from one, and that - not in the concentration - is where the value lies, the company said.

In a Q&A with ZDNet in August, Solaria CEO Suvi Sharma said makers of low-concentration panels are satisfied with lower magnification for several reasons. One is that the end products can have the same shape and size as traditional solar panels, making it easier for installers and competitive in a mainstream market.

Read more about Solaria here.