Earlier this month our family had a home energy audit conducted by Flemming Lund of Infrared Diagnostics. Although we have had an audit conducted before, Flemming's expertise in thermography led to some surprising revelations about our home's energy consumption.
With the weather warming up, one of his discoveries struck us as particularly relevant to the season. We've entered that wonderful time of year when the heat is permanently off. (The cute little Vornado space heater hasn't shown up on our TED display for weeks!) But, it turns out that there is an invisible network of miniature space-heaters continuing to heat our house, all the time.
Yes, little heaters, lying hidden all around the house: uninsulated water pipes, incandescent bulbs, and all of the other secret heat producers--the dishwasher, dehumidifier, etc. This essentially wasted heat, though useful in the cold months, is generally a sign of inefficiency - a water heater, for example, heating the uninsulated basement rather than the water you pay it to heat, in the form of energy bills. It would be like hiring a maid who spent 45 minutes cleaning the house, and then went out and dusted the gravel driveway for 15. (Incandescent bulbs, by the way, emit 90% of their energy as heat - which would be like a maid who cleaned the house for 6 minutes and then went outside Easter egg hunting for 54.)
In the summer, when you're trying to keep your house cool, the economics get even worse. For us, the system of pipes and appliances that quietly heats our house all summer just makes us a little less comfortable. In warmer climates, with air conditioning, it translates to the A/C working that much harder to keep the house cool - and as we know, air conditioning isn't exactly cheap.
For something like a stove, or a shower, good ventilation is the key to removing heat (as well as moisture, grease and pollutants). But the happy truth is that a good number of these hidden heat sources (which, incidentally, account for about 20% of total summer heat gain) can be dealt with fairly easily.
Water heaters usually come stock with insulation of about R-3 to R-6 - better than nothing, but not enough. Ideally a tank will have somewhere between R-15 and R-30, which can be accomplished with an insulating blanket made special for the task. (Check back in a week, our first shipment of blankets is due soon.) Hot water pipes, too, can be insulated with simple tube pipe insulation. Incandescent bulbs (a huge source of heat, as we found out in our audit) can be replaced with LEDs or CFLs. Under infrared inspection, the old halogen can lights measured 327 degrees, versus 105 degrees for the Cree LR6 LEDs.
Some of these steps we've already taken, and the rest - we're getting on them as we speak.
Comments
you did not mention that all fridges dump heat into your living space, but something can be done, you could duct that warm air up and out into an exhaust fan, by rights it ought to rise and let the heat escape w/o needing extra power.
Posted by derek visser on Jun 1, 2009 4:46pmventilation is indeed the secret, esp if you can draw col air from a basement, like i do and it's a lil bit too cool inside, i better close the outside window in the basement, to keep it cool for later!