Geothermal Heating and Cooling/Geothermal Technology

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Who this book is for[edit | edit source]

This book is meant for the general public, and for people interested in becoming qualified heat pump installers. It is meant to be read on its own, or used as a part of a course on Geothermal Heating and Cooling.

GEOTHERMAL TECHNOLOGY[edit | edit source]

Geo, short for Geological or earth based, Thermal for heat, All Geothermal Technologies have to do with taking heat from the earth, or giving it back. There are places where the fire from the middle of the earth runs close to the surface, and the earth is a passive store of solar energy, in places where that doesn't happen. And we don't have to just take heat from the earth, we can store heat there of our own instead.

This book isn't about the massive electrical stations that are built over fumaroles, nor about digging down to the magma layer to suck the superheated steam from the center of the earth, those type of projects are a little beyond the average person, and while they might exist somewhere, they are too expensive for the likes of most of the people in the world.

But if we could pump some of the heat out of the earth out, or pump some of the swelter on hot days into the earth, we could heat and cool our homes, our businesses, and our industries and maybe even for less than we are currently paying. The reason this technology is so cost-effective, is that it doesn't create heat, and so doesn't have to deal with latent heat, except in a positive way, instead it moves it from place to place using something called a heat pump.

For somewhere around $30,000.00 Canadian, you could heat your home for a cost a little bit more than the cost of running a refrigerator for about 3-4 times that you could heat a large business, or Industrial Plant. In some cases such as dual role buildings that have both a swimming pool and a skating rink, you can increase your relative efficiency to somewhere around 700% Most installations have only about 320% efficiency. But even that means that this has a relatively fast payback even though it has a high up-front cost. Part of that efficiency comes from the heat pump itself, but there are other heat pump technologies, for instance Air To Air heat pumps exist, but they must struggle to pump heat out of cold air because air has much less capacity for holding heat than water does.

In many places in the world Air to Air heat exchangers were not practical until their manufacturers developed two stage scroll compressors. However, for a little bit more money, you can achieve a significant jump in efficiency by going to Ground Source Heat Pumps because they use the same heat pump technology, but take their heat from the ground where there is more stored so you can use a smaller pump to pump the same amount of heat. It costs a little more because you have to get the heat from the ground into your building, but you don't have to dig down thousands of feet, in fact you seldom dig past 200 ft. Recently in many installations you don't even have to dig that far, in fact many installations are 4 to 12 foot deep.