by Tanada » Fri 23 Dec 2005, 05:34:25
$this->bbcode_second_pass_quote('Heineken', 'M')y electric water heater accounts for nearly 25% of my electric bill, which I believe is fairly typical. I'm trying to envision shutting off the water heater and living without hot water. I already wash clothes with cold water only (using hot water doesn't get your clothes any cleaner, I've read). I have a large woodstove (my only source of heat, which I fuel entirely with wood from my own land) on which I can heat water, when necessary, during the winter; obviously this approach won't work in the summer (but it's so hot here in the summer that a cold shower is a pleasure). I've experimented taking "sink baths" with just a wash cloth and soap and cold water, and it works pretty well. I don't have a dish washer; I've experimented with washing dishes with cold water and plenty of soap; again, it works better than I might have guessed, but one has to be careful to rinse thoroughly, since hot water does a better job dissolving and bearing away the soap.
I project savings on my electricity bill of at least $US 200 a year, not counting potential savings on the cost of the water heater itself (they need to be replaced every 12 years or so). More important, I take one more step toward financial and energy independence.
Am I crazy?
Being as you already use a wood stove you could make all the hot water you want with a little plumbing work. You can do it the easy way, get a small used gas water heater tank and put it atop the wood stove. Take the cold water piping and route it through a copper coil wrapped around the wood stove flue pipe, then into the tank. The cold water absorbs waste heat from the flue pipe, and enters the tank pre-warmed. If you can scrounge up more copper pipe you can add more to the back and bottom of the wood stove to soak up more heat that would be absorbed by the floor and wall behind the stove.
This would get you lots of hot water at a moderate flow rate any time the wood stove has been running for a half hour or so. I use electric for my hot water but I have a warming tank upstream, which is just a large tank without insulation. My cold water supply enters the warming tank at about 52 degrees F from the city supply, then sits in that tank until hot water is used. As water is drawn from my hot water tank it refills from the warming tank, which averages 65 degrees F because it is in the basement next to the hot water tank. The 13 degree F rise in temperature in the warming tank is 'free' energy that I don't have to use electricity for.