Editor’s Note: The following blog post is authored by our founder, Paul O’Grady, who said he was gob-smacked by the technology behind a tiny heating system that he discovered in a Swedish home. The find raised questions in his mind as to why we don’t have such compact, fuel saving heating devices here in the Bay Area. Here’s Paul’s take on his travels.
During a recent trip to Sweden, I was visiting a friend’s home and was impressed by a compact device tucked away just inside his garage. This strange-looking machine was just a bit bigger than our early generation home PCs, and was running fairly quietly unless I stood within two feet of the unit.
At first glance, I gathered it had something to do with heating the home, but I had no idea how it worked, considering its size and the extreme cold that comes standard with the Scandinavian climate.
When I asked my friend if he could explain this technology, I was told it worked just like a refrigerator, except the unit produced heat rather than dispelled it, and the heat was coming from the ground. As in geothermal. adsense ban . Hard to believe when you consider the frigid temperatures associated with Scandinavian countries such as Sweden, Norway and Iceland. But these little devices were cranking out heat to spare — and even hot water. And, I was told, during the rare hot summer day, these machines were equally effective as cooling systems.
How did the machine do all this in such a challenging climate? More important: Why on earth don’t we have such technology in the United States?
When I got back home, I did an Internet search and discovered this geothermal technology has been used in the United States — albeit sparingly — and even more infrequently in a residential application. That’s certainly not the case for homes in Sweden, where the device is as common as microwave ovens are here in the U.S.
Studies show that geothermal is five times more efficient than most standard heating sources, which translates to up to an 80 percent savings on heating and cooling costs. And there is no carbon footprint to speak of — that is to say if the electricity used comes from a clean energy source.
American inventor Robert C. Weber built the first ground-source geothermal heat pump in the early 1940’s. The first successful commercial geothermal project was installed in the Commonwealth Building in Portland, Oregon, back in 1948 and has been designated as a National Historic Mechanical Engineering Landmark by ASME.
The basic concept to this ground-source geothermal is to take an already compressed non-contaminating refrigerant and decompress it. This creates a much lower temperature that when sent through a loop in the ground under the home picks up heat from the earth. When the refrigerant completes the loop, it is again compressed to create heat, and the line goes over a heat exchanger, transferring that warmth for heating and hot water.
The system works off multiple loops and can operate in reverse to create cooler temps the same way — all the while producing hot water as well.
There are many ways to install a ground-source geothermal system. The most common are horizontal, vertical and pond/ lake closed loop systems. A ground-source geothermal system is more costly than a conventional heating system to install but is well worth the investment.
The implementation of the ground-source geothermal system will mostly be limited to a vertical closed loop system in a city environment such as San Francisco due to the proximity of neighboring properties. The new gymnasium for San Francisco City College is the first to use ground-source geothermal heating with 800 wells drilled into the ground. This can be done with a small home and only a few wells with the right R value on your home.
I live close to sea level, which means there is water about 20 feet below my home. This is ideal for ground-source geothermal since the water works well for thermal exchange. Perhaps some day the sounds of loud forced-air furnaces and ducts that clutter the precious space within our homes will be a thing of the past and our dependence on fossil fuels and natural gas will be greatly reduced.
Meanwhile, somebody at the national level in Washington, D.C., should grab a notebook and have a chat with some of those Swedes.
