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.
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.
RAIS Module – revolutionary monocrystalline PV module
* Onboard Cell Optimizing technology accepts reflected light without the hassle of complex tracker technology.
* Built-in shade tolerance and cell level MPPT produces more power in more real-world situations.
* Electrical architecture bypasses serial design limitations of traditional panels, creating a highly reliable and safer system.
RAIS Wave – racking system for the RAIS PV module
* Integrates Light-Smart reflectors.
* Meets ASCE-7 codes (up to 90 mph) on a commercial flat rooftop.
* Requires no roof penetrations.
* Generates the highest density energy output of any solar array on a commercial flat roof.
No Fire Hazards Within System or Module
Studies have shown that an arc can be sustained as low as 16VDC – meaning no matter how you break it down, a short in any traditional serial PV module means a risk of an arc fault and a fire. The short can be the result of poor PV module construction, poor installation or a loose connection made worse by hot and cold temperature cycles over the course of several years.
RAIS PV panel voltage is always less than 10 VDC – a level at which it is physically impossible to arc and start a fire and therefore completely safe.
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.