The earth absorbs almost 50% of all solar energy and remains a nearly constant temperature of 50°F to 70°F depending on geographic location. Working with an underground loop system, a geothermal unit utilizes this constant temperature to exchange energy between your home and the earth as needed for heating and cooling.

In winter, water circulating inside a sealed loop absorbs heat from the earth and carries it to the unit. Here it is compressed to a higher temperature and sent as warm air to your indoor system for distribution throughout your home.

In the summer, the system reverses and expels heat from your home to the cooler earth via the loop system. This heat exchange process is not only natural, but is a truly ingenious and highly efficient way to create a comfortable climate in your home.

Horizontal Loops are installed in areas where the soil conditions allow for economical excavation. Taking up more land area than any other loop type, they are used where space permits. Trenches are normally 5 feet deep. Normally, several hundred feet of trench is required.

Vertical Loops
Vertical Loops are used extensively where land area is limited. A pair of pipes with a special U-Bend assembly at the bottom are inserted into a bore hole that averages between 150 to 250 feet in depth per ton of equipment.

Some cost comparisons;

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However, a researcher at the University of Missouri-Columbia discovered that the development of a plug-in fuel cell hybrid, with as little as 20 miles of range from rechargeable hydrogen, could cut the amount of gasoline consumed in the United States by more than 50 percent. In addition, this technology could be mass produced in the next five years.

“About 47 percent of all miles put on vehicles in a day are within the first 20 miles of travel,” said Galen Suppes, associate professor of chemical engineering at MU. “Furthermore, about 50 percent of the vehicles travel 20 miles or less per day, and this 20 mile distance is usually in inner-city travel where fuel economy for conventional internal combustion engines is poor and emissions have their greatest adverse affects.”

The plug-in hybrid is a modified version of the hybrid vehicle, which uses electric motors and battery packs to improve fuel efficiency. The plug-in contains a secondary power source, larger than the standard hybrid, which can be recharged using electricity while parked at home. Suppes says that by replacing vehicular fuel consumption with electricity, there will be a drop in fuel emissions and less demand for gasoline. If the vehicles were charged at night, according to Suppes, they would not add to the burden on the nation’s electrical power grid.

The fuel cell hybrid provides an additional degree of freedom with the plug-in option, Suppes found. The electricity could be used to recharge batteries or to hydrolyze water to hydrogen for use with the fuel cell. In the hydrogen storage option, fuel cells are used to generate hydrogen and oxygen which are stored in compressed tanks. This configuration, Suppes says, can reduce the amount of secondary source battery storage since pure hydrogen can power the fuel cells.

“At less than $1,000 in incremental costs to today’s standard hybrid vehicle, this is a good option today and a great option for tomorrow’s fuel cell hybrid vehicles,” Suppes said. “The plug-in fuel cell hybrid is a great transition technology toward a hydrogen infrastructure.”

Suppes’ research on the plug-in fuel cell hybrid was recently published in the International Journal of Hydrogen Energy. He and his colleague, Truman Storvick, professor emeritus of chemical engineering at MU, recently developed an online book, “Energy Disclosed: Abundant Resources and Unused Technology,” which can be viewed at http://www.missouri.edu/~suppesg/book.htm.

Adapted from materials provided by University Of Missouri-Columbia.