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COLUMNIST: Geothermal heat pump opps open

One of the requirements for technical school instructors is that we have one or more advisory board meetings each year. Administrators assumedly know how to administrate, but rarely know whether we instructors are doing a good job. Bringing in contractors out of the field theoretically does several things. They bring in new trends, ask for changes in your program based on their experiences with your graduates, and should you not be doing your job well, pass that information on to school administrators.

At my HVAC advisory board meeting the other night, the federal government's energy tax rebate program was front and center in the discussion. It seems that there's a problem with air source heat pumps. (They're like an air conditioner which can move heat from inside your house air to the outside, PLUS they can reverse in the winter and move heat very efficiently from outside air, usually above 20 degrees, into the home. They operate on electricity, and can be installed on most forced air furnaces.) The new standards are set so high that not only do you have to have the very best--read, most expensive--of these heat pumps, but they can only meet the high energy consumption standards in concert with a very expensive, variable output furnace.

All across America, contractors and manufacturers have suddenly realized this, and are scrambling to find equipment suitable for these new high standards. They're having limited success.

Even more importantly, they're finding that, when the customers find themselves faced with costs far higher than they had expected to face, very few sales are being made. Everyone wants to save money on their heating costs; but, not everyone has the financial wherewithal to spend what is surely going to be several thousand dollars to do it.

Add in the fact that the folks being hurt the worst with high heating costs are likely already struggling to make ends meet, and are not paying much income tax. Do that, and then tax rebates for high priced hvac equipment don't do middle America's wage earners much good.

At first, the 30 percent rebate, max of $1,500 per year but carryable forward to the next tax year, looked great to all of us. Sure, it's still available on lots of other stuff, like insulation, better windows, etc., but we were sure disappointed when pretty good air source heat pumps didn't make the cut.

Now let's briefly talk about solar. I went out and measured the heat output of one of the new-generation solar hot air collectors, and was very impressed with the output. Priced at under $2,000, then subtract the 30 percent rebate, I agree with the company's estimated return on investment of less than 10 years. I'm going to get one.

Geothermal: Although HVAC contractors are disappointed about the air source heat pump standards, they're absolutely thrilled about the new opportunities that have opened up for geothermal heat pumps. Geothermal heat pumps circulate water through the earth and into the house, where a heat pump moves the earth's heat out of it and sends it back to warm up again. Since the ground temperature is a pretty steady 40-something degrees, and since heat pumps can get over three cents of energy out of that water for one cent, geothermal shines at providing low heating and cooling bills.

Geothermal is a high-cost technology, and has in the past appealed mainly to higher wage earners, since costs routinely approach $20,000 for fairly average-sized homes. However, the federal tax rebates in combination with substantial rebates from your electrical utility provider are proving to be a combination that is much more attractive.

Heating bills of well under a hundred bucks a month for even larger homes are routine for geothermal systems. Hence the attraction, and good pay-back potential, despite high up-front costs.

There are three methods of tapping the earth's heat. One is called the slinky method. It requires a lot of acreage, and trenches that are four feet wide and at least 9 feet deep. It disrupts a lot of square footage, works well in heavy soils and high water table locations, like in and around a large slough, or swampy area. Water is circulated through thousands of feet of buried piping. This is called a closed system.

Another is called pump and dump. Water is directly pumped up out of a well, the heat pump adds or extracts heat from that water, which is then pumped either into a swamp or slough--maybe a lake, although the DNR has something to say about that--or back down another well. This allows a lower-priced up-front cost, but isn't available to everyone, and may have environmental impacts that aren't so good. This type is called an open system.

Finally, most geothermal systems involve wells drilled down a hundred-plus feet, into which tubing is inserted, through which water is circulated. The wells are expensive, but don't take up any more room than the average lawn, under which you wouldn't even know they were there. You figure one well for each 12,000 Btu's needed, and at $1,600 to $1,800 per well, here's where costs add up.

There are electrical utility companies (Well, I know of one in another state.) out there who are financing the cost of the wells and charging the homeowner a modest per-monthly fee. Maybe that'll happen here, in which case a lot of people will become more interested.

"So," I asked my local electrical coop, "can you guarantee me that electricity won't double in the next three to five years?" I asked that because they make electricity from coal, which puts out a lot of carbon dioxide, which is the increased focus of governmental regulation. This attention is coming in the form of carbon credits to trade or limit, and they aren't credits at all. They're expensive.

"Until we know how expensive this new carbon regulation is going to be, we're not sure about future costs." That sums up what I was told.

Sure. Electricity is going to go up, but then, so will fossil fuels.

Electricity, in the form of heat pumps, is still pretty attractive, air source or geothermal.