TenagaSurya

TechnologyReview: More Power from Rooftop Solar

Posted in Solar Panel by TenagaSurya on April 30, 2011
asSalaamu’alaykum.
ENERGY

More Power from Rooftop Solar

A startup says technology inspired by RAID hard drives can boost power output by up to 50 percent.

Dark Mirror: Solar panels (with silver lines) are paired with reflectors (the solid dark material) to increase the amount of power a rooftop array can generate.
Credit: TenKsolar
FRIDAY, APRIL 29, 2011 | BY KEVIN BULLIS
A startup called TenKsolar, based in Minneapolis, says it can increase the amount of solar power generated on rooftops by 25 to 50 percent, and also reduce the overall cost of solar power by changing the way solar cells are wired together and adding inexpensive reflectors to gather more light.
TenKsolar says its systems can produce power for as little as eight cents a kilowatt-hour in sunny locations. That’s significantly more expensive than electricity from typical coal or natural-gas power plants, but it is less than the average price of electricity in the United States.
Solar cells have become more efficient in recent years, but much of the improvement has gone to waste because of the way solar cells are put together in solar panels, the way the panels are wired together, and the way the electricity is converted into AC power for use in homes or on the grid. Typically, the power output from a string of solar cells is limited by the lowest-performing cell. So if a shadow falls on just one cell in a panel, the power output of the whole system drops dramatically. And failure at any point in the string can shut down the whole system.
TenKsolar has opted for a more complex wiring system—inspired by a reliable type of computer memory known as RAID (for “redundant array of independent disks”), in which hard disks are connected in ways that maintain performance even if some fail. TenKsolar’s design allows current to take many different paths through a solar-panel array, thus avoiding bottlenecks at low-performing cells and making it possible to extract far more of the electricity that the cells produce.
The wiring also makes it practical to attach reflectors to solar panels to gather more light. When solar panels are installed on flat roofs, they’re typically mounted on racks that angle them toward the sun, and spaced apart to keep them from shading each other over the course of the day. Reflectors increase the amount of light that hits a solar array, but they reflect the sunlight unevenly. So in a conventional solar array, the output is limited by the cell receiving the least amount of reflected light. The new system can capture all the energy from the extra, reflected light. “The small added cost we put in on the electronics is paid back, plus a bunch, from the fact that we basically take in all of this reflected light,” says Dallas Meyer, founder and president of TenKsolar. “We’ve architected a system that’s completely redundant from the cell down to the inverter,” he says. “If anything fails in the system, it basically has very low impact on the power production of the array.”
The reflectors use a film made by 3M that reflects only selected wavelengths of light, reducing visible glare. The material also reflects less infrared light, which can overheat a solar panel and reduce its performance.
Meyer says the system costs about the same as those made by Chinese manufacturers but produces about 50 percent more power for a given roof area. Power output is about 25 percent higher than from the more expensive, high-performance systems made by SunPower, he says.
The new wiring approach does have a drawback: because it’s new, the banks that finance solar-power installations may have doubts that the system will last for the duration of the warranty, and this could complicate financing, says Travis Bradford, an industry analyst and president of the Prometheus Institute for Sustainable Development.
TenKSolar, which has so far raised $11 million in venture funding and has the capacity to produce 10 to 12 megawatts of systems a year, is working on partnerships with larger companies to help provide financial backing for guarantees of its products.

SOURCE: TechnologyReview: More Power from Rooftop Solar

2 Responses

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  1. TenagaSurya said, on April 30, 2011 at 11:29 pm

    From: “SolarPowerForum.net” Date: Sat, 30 Apr 2011 13:02:02 -0500 (CDT)
    Subject: Reply to thread ‘TechnologyReview.com: More Power from Rooftop Solar’

    Dear TenagaSurya,

    russ123 has just replied to a thread you have subscribed to entitled – TechnologyReview.com: More Power from Rooftop Solar – in the Energy News & Announcements forum of SolarPowerForum.net.

    This thread is located at:
    http://www.solarpowerforum.net/forumVB/energy-news-announcements/5630-technologyreview-com-more-power-rooftop-solar-new-post.html

    Here is the message that has just been posted:
    ***************
    That is one rather silly article that has been debunked a thousand time on the web – months back.

    Of course they would be happy to take money from investors.

    Best Regards,
    Russ
    ***************

    There may also be other replies, but you will not receive any more notifications until you visit the forum again.

    All the best,
    SolarPowerForum.net

  2. TenagaSurya said, on May 1, 2011 at 9:00 am

    Reserved


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