There is a saying about the calculator - the first one cost a billion dollars, but the second one cost a dime.  It may not be long now before photovoltaic (PV) technology becomes just as common, and cheap, as the calculator.

Industry has been working hard and investing a great deal of money to bring this technology to the point that the average American can use it to convert sunlight into electricity for their homes and businesses.

Sunlight is made up of photons that are absorbed by electrons in atoms in a semiconductor plate.  The extra energy from the photon allows the electrons to break free and escape in the form of electric current.

The key material in semiconductor plates or photovoltaic panels is silica sand.  Silicon is the second most abundant element found in nature, and silica sand is a very cheap raw material.  This is important because it will lead to the economic production of PV products.

The newest PV product on the market is a “thin-film laminate” product called “EnergyPeak,” manufactured by a collaboration of CENTRIA Services Group and UNI-SOLAR (United Solar Ovonic, LLC).  It is designed specifically for use with standing seam metal roofs.

CENTRIA is a manufacturer of metal roof and wall panels, and UNI-SOLAR is a world leader in thin-film amorphous photovoltaics technology.  EnergyPeak will be made available to other manufacturers of roofing panels as well. 

The unique thing about this product is that in comes in 16- or 18-inch-wide rolls that easily mount to existing or new metal roofs with a high-bond adhesive.  This has solved one of the biggest objections to mounting devices on a metal roof – no screws or drilling is required, so this eliminates the potential for roof leaks.

The thin-film is made by laminating a 5-mil-thick sheet of stainless steel with a sheet of plastic.

Another unique feature about this product is that it is far more efficient than other PV products on the market.  EnergyPeak absorbs three different wavelengths of light, increasing its electrical output.  Not only does this provide more electricity, but it also reduces the payback time for the initial installation costs. 

CENTRIA’s director of marketing and business development states that “it will no longer take 10 or more years to see a worthwhile return on investment.  In fact, when taking into consideration the rebates and tax credits available, many applications have a return on investment of half that time.  It’s also worth noting that a solar system increases the value of a building, a benefit that will continue to become more significant as the push for sustainability continues.”

CENTRIA has also developed software that will analyze the system being installed to determine its payback period and the cash flow expected over a 25 year period based on the system’s power output.

The weak link in the PV system is that it doesn’t produce power at night, and during the daytime it may produce more power than can be used.

One solution to that problem is to use the excess power to charge batteries, but batteries are not very efficient storage devices and are expensive to replace.  Industrial Chloride batteries, similar to deep-cycle batteries used in golf cars, appear to be the best type available thus far.  Eventually, new battery technology will solve this problem.

The second solution is to sell excess energy back to a power company via the power grid or “net-meter” the power using a bi-directional electric meter that allows you to pay only the net amount of power that is used.

Though it might take a 100 years, the real goal should be to reduce or perhaps even eliminate the power grid.  Our fragile power grid is a real national security risk, and the loss of power (as we discovered in our recent ice storm) can cause serious problems.  Through the use of photovoltaic energy, the reduction in energy costs would be significant, especially considering installation and maintenance costs involved in operating a power grid.

Photovoltaics are an important part of America’s future.  As it becomes more available and as the price drops, it will help reduce our dependence upon foreign oil.  It has the potential for completely recreating our industry base, as we switch from traditional coal-fired or nuclear power plants to using nature’s most abundant, clean and reliable energy source – the Sun.

Randy W. Bright, AIA, NCARB, is an architect who specializes in church and church-related projects. You may contact him at 918-664-7957, rwbrightchurcharch@sbcglobal.net or www.churcharchitect.net.

©2008 Randy W. Bright

Previous articles written by the author are available for reading at his website.

This entry was posted on Thursday, January 31st, 2008 and is filed under Columns.