Wednesday, December 9, 2009

Kicking the Fossil Fuel Habit

Our house uses a "combo" heating system - an oil-fired hotwater tank that provides both space heating and domestic hot water. Two years ago when oil prices were higher, I installed a small electric hot water tank to pre-heat the water with electricity before the oil-fired hot water tank. I described this conversion in a previous post here. That conversion was saving us about $50 a month in energy and reduced our greenhouse gas emissions by 70% to 1.6 tonnes of CO2 / yr (Yukon average is about 12.6 tonnes / person / year)

A couple of months ago the insurance company decided to do an inspection of our home (we built it 5 years ago and they've never actually seen what they are insuring). Well, the inspector happened to notice that our above ground fuel oil tank does not have a "sticker" on it, and gave us 4 months to get it replaced. Now, this fuel tank is perfectly fine, but I had salvaged from the house we tore down previously. Given the fuel tank's age, it doesn't have a CSA sticker. We got a quote to replace the fuel tank, and due to the new code requirements for seismic tie-down, concrete pad, etc, it was going to cost us $2500 to get a new tank installed.

I've wanted to get off the oil for a while now, so I thought if my little pre-heat tank is providing 90% of my water heating already, why not go all the way with electric? In Whitehorse, our electricity is pretty green: in 2008 99.94% of our electricity came from renewable (hydro and a bit of wind) . The advantages of getting off oil include:
  • reduction in GHG emissions associated with our house
  • reduced risk of backdrafting (indoor air quality)
  • reduced heat leakage up the chimney (my chimney always had a lot of air rising in it, constantly sucking heat off of my hot water tank)
  • no annual maintenance on the oil burner (a savings of ~$200 /yr)
  • no worries about running out of fuel/fillups, etc.
  • no worries about oil leaks
  • reclaimed 15 sq. ft. of yard where the fuel tank used to be (living in downtown, I value every square foot of yard I have!)

I looked into an electric boiler first, but we only have a 100A service, so that looked like it was out of the question (replacing a electrical service can be big $$). As an alternative, I got a the largest electric hot water tank from Canadian Tire - it is 60 gallons and has a big heating element at 5.5 kW. So, combined with the little hot water tank, I have a total of 8.5 kW of heating. My house has a peak heating load of around 34,000 Btu, which is 10 kW--this means the heating system is a bit undersized, however I mostly heat with wood, so this is fine, it is adequate to keep the house from freezing up if were away!

Total cost to me?
  • Hot water tank: $560
  • Wire, new 35A breaker and electrical permit: $105
  • Plumber: $260
  • Stevie bucks (renovation tax credit): $-79
  • Total: $846
And that's not counting the $200 I saved on not doing burner maintenance this year! Now our house GHG emissions are just 0.19 tonnes / year from our propane cook stove.

So, anyone want to by a perfectly good 5-yr old oil-fired hot water tank? For sale, cheap!


No comments: