Guest Column - September 2009
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Design Corner

Clean & Free Power

By Dave Hammel


aced with the potential of ongoing funding cutbacks, now is the opportune time for community recreation centers to take a hard look at the potentially significant savings offered by solar power.

Once considered an expensive and exotic energy source feasible in only the sunniest of climes, solar energy today can be used effectively most anywhere in the country. And the increasing number of federal, state and local tax credits and incentives has made solar an attractive economic alternative to natural gas, propane and other traditional fuels.

In one hour, more sunlight energy falls on the earth than is used by the entire world population in one year. Recreation centers use more energy per square foot than schools, hospitals and office buildings. Therefore, it behooves recreation center operators to see if capturing some of this abundant sunshine power makes sense.

There is no question that a recreation center's location and the relative cost of local energy sources are important in determining the feasibility of solar. A center in a community with abundant sunshine and relatively high natural gas prices is a prime candidate. But an increasing number of public buildings in the Midwest and Northeast, where sunshine is scarcer and energy prices are high, are using solar systems to their advantage.

It is generally more cost-effective to incorporate solar systems in a recreation center's original design. However, there can be significant savings from add-on systems as well. If, for whatever reason, solar was rejected or not even considered when the center was built, it is still prudent to take another look. A lot has happened in the solar power arena during the past five years.

Thermal solar systems are particularly well suited for recreation centers where swimming pools act as large storage tanks providing year-round heat for pools and showers. Recreation centers with natatoriums can spend as much as a third of their energy bill heating and sanitizing the swimming pool water and providing warm, clean air in the indoor swimming environment.

The two thermal systems most in use today are the glass flat plate collector and the plastic absorber collector. The glass flat plate collector, which uses antifreeze as a heat transfer fluid and a heat exchanger, is the most efficient (85 percent) and most expensive ($80 to $90 per square foot of collector area). The plastic absorber collector is about half the cost of the flat plate collector but considerably less efficient. It heats pool water directly and is best used for seasonal outdoor pool heating.