July 28, 2009

Re-focusing on the problem - a better solution

Large Photo-voltaic generating arrays require large synchronous inverters if you are planning to intertie with an existing power grid. A synchronous inverter syncs up with the 60 Cycle current of the grid and allows the two to flow together without any phase lead or lag and it gives an efficient flow of power. Needless to say, given the large power capacity of the switching circuits, these are nosebleed expensive. Enphase Energy looked at the problem from a different angle and came up with a wonderful idea... The circuitry used to determine the phase of the power and give the inverter the ability to sync with the power line used to be very expensive. Now it can be done with a simple $5 microprocessor and another $5 of "chip glue" (ancillary components). The power transistors are still very expensive -- disproportionately so as fewer of these are called for and made than the lower power transistors. What Enphase Energy is doing is very cool -- from C/NET News Green Tech:
An inverter in every solar panel?
Enphase Energy said on Tuesday that it has raised $15 million to ramp up production of its microinverters, a design that it claims significantly boosts the power output and reliability of solar panels.

Rockport Capital Partners led the series C financing, which was joined by existing investors Third Point Ventures and Applied Ventures, the venture capital arm of solar equipment manufacturer Applied Materials.

Enphase Energy's CEO Paul Nahi said the company raised money earlier than anticipated because it's seeing strong demand for its microinverters, which can improve the energy capture of solar panels by 5 to 25 percent.

Solar photo voltaic panels generate direct current from sunlight. An inverter, often placed on the side of a building, is needed to convert that direct current to the alternating current that comes out of electrical outlets.

Typically, one single inverter is dedicated to a rooftop array of panels for a homeowner.

Enphase Energy, by contrast, has built a DC-to-AC inverter that is placed on each single panel.

That design is more reliable than a centralized inverter and more efficient, so panels can generate more electricity, Nahi said. The company started shipping its microinverters earlier this year and has signed on with a number of panel distributors and installers, he said.
Obviously for now, these will be high-ticket items but once the technology matures (five years) they should be very very cheap. Fun time to be alive! Posted by DaveH at July 28, 2009 2:25 PM