Thursday, December 17, 2009

Proof of Concept

This is a photograph of a momentous occasion. It may look somewhat anticlimactic. So, what is this momentous thing we are looking at?

You are looking at the "furnace" that heats my 30' x 70' x 12' shop. 2,100 square feet. 25,000 cubic feet. This should strike you as improbable, if not impossible. Think about how big your furnace is. Look at mine again.

This is a cheapo two speed electric heater like you could buy at Wal-Mart for around twenty bucks. On low, it uses 1,000 watts. On high is uses 1,500 watts. This is about the same as the average hand held hair dryer. In the recent very cold weather (like down into the single digits Farenheit), this little heater, set on low, kept my shop between 45 and 50F. 1,000 watts of heating power have kept my shop very comfortable.

This is the same as saying, I could have ten 100 watt lightbulbs plugged in, and my shop would stay comfortably heated. This is about an order of magnitude less than any other shop that I have seen.

Just by comparison, one kilowatt (one thousand watts) = 3,412 BTU/hr. A typical home furnace could range between 80,000 BTU and 120,000 BTU's as their maximum rate of heat output per hour. Of course, most furnaces don't run 100% of the time. So, if your furnace runs 1/3 of the time, and it's at the small end of the scale, that would compare like so:

80,ooo/3 = 26,667 BTU's per hour. or

(26,667 BTU/hr) x (1,000 watts/3,412BTU/hr) = 7.816 kilowatts

Thus, your average house with a small furnace will use energy at a rate of almost 8 times what my shop does.

In money terms, I pay seven cents per kilowatt hour. So, that looks like:

1kw x .07 x 24hrs x 30 days = $50.40 to heat my shop for a whole month, in the middle of winter, using electricity. If I could find a natural gas or propane heater small enough, it would be less than that by a substantial margin.

I have planned and saved and worked and worked, and worked some more to achieve this. On paper, I knew it should work. In reality, one has doubts of course. There are still a few loose ends to tie up in the shop that will improve thermal performance even more, but I am already ecstatically happy at the proof achieved so far. And very relieved.

Of course, we will have phase two when we get the house done up to similar specifications. Now, the house presents a few obstacles that may prevent us from attaining quite the same level of energy efficiency and independence. Most notably, all those windows. Hey, maybe we'll have to plug TWO heaters in to keep the house toasty. And of course, we want the house to be well above 50, more like 70'ish.

Yet, I feel fully confident that the wood stove and/or the oil stove will keep the house toasty on a tiny fraction of the energy we currently use. There are other people who have built similar superinsulated houses that heat the house for an entire canadian (Ontario) winter with the firewood that fits in the back of a pickup truck.

I cannot recommend this method highly enough for anyone considering building or remodeling. It is not that complicated. It is not that expensive. It has a relatively short payback period for most situations. It does not wear out or require expensive maintenance like heat pumps. It requires no maintenance or upkeep whatsoever. It requires no special attention or skills from the homeowner to "operate". It, effectively, has no moving parts. Compared to the stock market, this looks like an absolutely sure deal. Plus, it saves "after tax" dollars, which, depending on your tax bracket, makes the savings look 15-35% better than the raw number. The government hasn't quite found a way to tax you on money you don't earn and don't spend, yet.

If I am correct in predicting that all energy costs will become very volatile over the next decade or so, and I am further correct in predicting that the general trend will be for higher fuel cost trends (higher highs and higher lows), this technology will only get more financially attractive, not less. I would also expect that as consumers become keenly aware of their monthly energy costs, it will become an excellent real estate investment that will more than pay itself back if you sell such a house.

This has a second corollary that, if I am correct about the energy forecast, the economy may take 10-15 years to "recover" from it's present state. So, anything you can do to control your unavoidable costs, like heating and cooling, will only help you stretch your budget when you are faced with relatively static or falling income, but ever increasing expenses.

The cost of insulation and framing for a new, stick built house, hovers around 15%, give or take quite a bit depending on where you live in the country, and how hungry your contractor is at the moment. So, on a $125,000 house, we would pay $18,750 for framing and insulating a conventional house, and almost exactly double that for a superinsulated house, or $37,500. But really, we're interesting in the economics of the additional $18,750. If financed on a fixed 5.5% 15 year mortgage, that would raise your monthly mortgage payment by $180.55.

If you live anywhere north of the Mason-Dixon line, your savings in heating costs alone, along with a much smaller furnace, should pay for its own way the first year. If you live south of the Mason-Dixon line, savings may not be quite as impressive, but your cooling AND heating costs, will very nearly pay for its own way the first year. If you like the house cool in the summer, you will probably break even.

You have basically traded an energy expense for a mortgaged framing/insulation expense. Further, this mortgage has a finite life of 15 years in this example. After 15 years, the expense goes away entirely, while the energy savings goes on for the life of the structure, saving enormous piles of money, energy and environmental damage while adding to equity value of the house. A green lifestyle that pays you back in money. What's not to like?

Finest regards,

troy and christina

1 comment:

David said...

That's fantastic Troy! It is great to see the tangible energy savings after all that work. I can't wait to superinsulate a house someday. Keep paying those taxes :)

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