Your energy resources

Feb. 22, 2009

Your energy resources
Harley L. Sachs 2/23/09

Most of the energy you need lies beneath your feet and in the sky above, and there’s no need to create CO2 to utilize it. As any cave explorer can tell you, the average temperature of the earth in Michigan is about 45 degrees F. Drawing upon it, you can heat or cool your house.
Take geothermal energy: An engineering professor at Michigan Tech University sought out the longest flexible plastic pipe he could find so each would make a loop in the soil without a vulnerable joint. He buried a number of plastic pipe loops in his yard, bringing the ends into the basement and connecting them with a heat exchanger. Filled with many gallons of antifreeze, the underground radiator thus formed could be tapped for the temperature of the earth.
A heat pump sucks warmth out of the ground in winter and pushes heat out of the house and into the ground in summer.
Result: the professor’s home was heated to 45 degrees by warmth from the earth during the winter months. From there, his furnace did the rest to warm his home to 72 degrees. This produced a huge savings over warming his home the traditional way from outdoor temperatures of as much as 30 below zero.
The MTU professor who built his underground heat source said the break-even point on the installation was about 10 years. After that, your basic geothermal power is free of charge.

ADDING SOLAR
Ah, but what about the electricity for the heat pump? The pumps run on 110 volts AC. Even with the ground as a heat/cooling source, there’s still the energy needed to run the heat pump, although it’s a pittance compared to other means of heating your house. Time to add solar energy to the equation.
Solar energy is getting more and more efficient and the costs are coming down. The original silicone wafer solar cells of the 1970s were fragile, heavy and expensive. The current third wave of solar development uses thin, flexible foil that’s so durable that current 20-year warranties are expected to run as high as 50 years.
Nanosolar installations (which produce electricity from the sun) can bring the cost down to a dollar a watt, an amount comparable with electricity generated from coal. Of course, a typical solar energy system requires a bank of batteries and an inverter to convert the DC power to AC, which doubles the cost. However, if the excess electricity generated by a solar collector is fed back into the electrical grid and sold to the power company during the day, then bought back from the power grid during the night, no storage batteries are needed.
If you think solar panels need to be huge, consider that the Sharp company has placed its panels on over 500 navigation buoys in Japan. The lighthouse at the lower entry to the Keweenaw Waterway is also now solar powered. The high intensity flashing light and the foghorn are independently powered by the sun. The heavy electric cable that used to connect the lighthouse with the power grid has long since been removed; and the heavy steel shields have been removed for recycling.
Then too, Google in California owns a number of electric cars which are plugged in daily in a garage whose roof is one huge solar panel.

THE ULTIMATE SOURCE
All of our energy ultimately comes from the sun. The power of the sun evaporates water from the lakes and seas, which is then precipitated as rain for the reservoirs and hydroelectric power dams. The oil and coal we find in the ground is the bi-product of vegetation which grew millions of years ago, courtesy of the sun.
Unfortunately, the U.S. Department of Energy devotes only one percent of its research money to solar. It that were merely doubled, the possible advances in this technology would be huge.
Perhaps the political clout of the power plants has held back essential research. Coal-fired plants and the coal industry see this new technology as a threat. It’s a bit like what the car, gasoline, and tire companies did when they bought up and dismantled electric streetcars in favor of the construction of more highways as Americans became hooked on the automobile.
With a little research, forethought, and planning, a home owner can look to that great nuclear reactor in the sky for inspiration and solutions to home energy problems. Think long term efficiency. Think solar.
For more of the writings of Harley Sachs, see hu.mtu.edu/hlsachs.