Tapping the Earth
It produces NO byproducts, recycles its own energy transmission source. It requires no new technology7 and it is both inexhaustible and utterly reliable. What is the sacrifice? We have to exploit 2 of our biggest national parks for energy.
Both the Japanese and Iceland make extensive use of this power and have for decades.
Look down, Marcus. Enough power for millennium lies beneath or feet. Geothermal energy could supply all of our electrical needs.
At Yellowstone and Long Valley in California are 2 of the biggest Calderas on Earth and using them to power our electric grid is the single most intelligent thing we could do.
What is standing in the way? Mass market mass. That is to say, the demand for it is not yet great enough for serious production of the gear needed.
The Empress and I are building a house. I have a bid from a local company for a traditional heating & cooling system. The system is bid out at about $11,000.00 for the duct work, the furnace the air conditioning (AC), and venting. They wanted about another $11,000-$12,000 for an earth-heat pump system.
Now, I am quite willing to consider this as an investment that will pay off given the time. Reading I have done says many of these installations pay off in two to ten years time. Not bad, that time frame is something I am okay with.
However, the bid did not come with an analysis of likely savings so it is a shot in the dark. So, I am going to either punt on this, call and ask where the analysis is, or go somewhere else. The outfit did not impress me.
How Earth Heat Pumps Work
Essentially it is an AC unit.
Using the principles of physics your basic AC (or refrigerator) collects heat and moves it from one location to another. The AC moves the heat from inside of the house to the outside. A refrigerator moves it from inside the refrigerator to the outside of the refrigerator. Simple, no? A furnace, on the other hand is a heat source, you convert one form of energy to heat energy and move that heat about your house. For most of us the energy we convert is the chemical energy of natural gas, fuel oil, or wood (or any other combustible) to heat energy. Some of us use electrical energy as the heat source.
Heat pumps rely on the difference in temperature to generate heating and cooling. In the summer the earth heat pump transports heat from the house to the earth and in the winter the pump reverses and moves heat from the earth into the house.
Understand, heat and temperature are not the same. A spark generated by metal on a grinding wheel has a high temperature but next to no heat. It will dance on your skin and startle but not harm you. The earth down in the ground stays at about 50° F but is able to absord & give massive amounts of heat without a change in the temperature. This is the key.
The heat pump through its action concentrates an amount of heat into a liquid which is (you can put it through your water heater first) then pumped into the earth and then the earth cools the liquid to 50° F or close to it. The liquid returns and is ready to be reheated. Again, in the winter reverse the process, send cool liquid to the earth and then on return concentrate the heat in the liquid and distribute through the house.
In fact, some heat pumps do not go into the earth but will just use the outside air as the heat sink/source.
Two General Types of Systems
Vertical & horizontal. If you have a lot of land you can have a horizontal system where a shallow trench is dug and tubing is laid out and buried. There you have your heat source/sink. If you do not have a lot of land then a vertical sysem is in order. A deep shaft is dug and the heat and the piping is buried in the shaft. Obviously vertical systems are more expensive.
I will have to do a bit more research on this for us.