Why AC At All? | Green Energy News

July 18, 2004 – Vol.9 No.17

WHY AC AT ALL?

The way we utilize electricity is kind of, well, crazy. Electricity flows into our homes as high-voltage alternating current (AC) and then before it is used it is converted - inefficiently - to power many direct current (DC) devices.

Our televisions, computers, wireless phones, microwave ovens, fluorescent lights, and host of other devices all operate on AC-converted-to-DC current. The inefficiency is noticed as heat loss.

(Carefully touch the plastic box at the wall plug end of your cell phone charger. The warmth you feel is the loss of energy in conversion of high voltage AC to low voltage DC to charge your cell phone battery.)

In our homes, with current technology (no pun intended), only electric ranges, electric clothes dryers and electric hot water heaters require high voltage AC current. Incandescent lighting systems really don’t need AC current. Popular low voltage halogen lights, for instance, really operate on AC house current converted to DC. Large electric motors, such as those in heating and cooling systems, don’t have to be AC powered.

And there’s even a sillier practice. If we are lucky enough to have solar power for our homes an inverter is usually installed to convert DC electric current from the solar panels to AC current (at a loss of energy) to flow through a home’s electric system which, often, is converted back to DC (at another loss of energy) to operate all those DC devices.

Nextek Power Systems thinks it may be time to move beyond the AC paradigm and begin to embrace DC.

The company has developed a power router known as Direct Coupled (tm) power solutions that enables the integration of multiple sources of power - the grid, the rooftop PV system, the small wind turbine, or someday a fuel cell - to power our homes or businesses. The device will choose the local source of power first, such as the rooftop solar system - and be able to supplement or (complement) that power from elsewhere, such as the grid, if it is needed.

So why AC at all? AC was developed as a way to send electricity over long distances from large centralized power plants. In short, AC allowed the creation of the regional electric utility company.

Nextek has just received additional investment in the form of Steelcase Incorporated shares through the Peter Martin Wege Trusts. Visit the animation of the Direct Coupled power solution at http://www.directcoupling.com/ and additional pertinent information at http://www.nextekpower.com/