At a meeting between oil executives and environmentalists in Alberta two weeks ago, it was, says CBC, roundly agreed that there should be a price on carbon and that everyone should pay it. Let’s look at how things would be, if there were a carbon tax on home heating.
There are many ways to heat your home. Almost all of them involve burning something, usually some carbonaceous fuel. Some of the well known “fuels” are:
- Heating oil.
- Natural gas.
I put quotes around the word “fuels” because of the last item on this list, electricity. It is not strictly a fuel, but as consumers we use it like we use other true fuels. Plus, we can compare its “waste” product directly with the waste products from the true fuels.
The issue of waste from home heating is pertinent, because household waste in general is at the top of everyone’s mind. Our conception of household waste is confined mostly to garbage. We are intimately familiar with that kind of waste—it’s the stuff you generate in the normal operation of a household. Vegetable peelings, used coffee filters, packaging, burned out lightbulbs, old clothing. You take this stuff out of your home and place it in a designated area where someone else takes it away and brings it to a landfill.
Then there is what I will euphemistically call liquid waste. It goes down household water drains and toilets. Enough said.
We all have a general idea of how much solid waste we generate; we are the ones who remove it from our homes. It is measured in the size of the (usually) plastic bag we put it in before tossing it. Mass-wise, in Canada it is about 2 kilograms per day for every man, woman, and child. It costs $104 to put a metric ton into my municipal (Ottawa, Canada) landfill, so my daily 2 kilograms of garbage costs about 21 cents. As for liquid: well, most of us in Canada each use on average about 200 to 250 litres of water per day—that is about 200 to 250 kilograms. Most of that goes back into the municipal sewer.
We pay for our solid and liquid wastes, mainly through municipal taxes. The solid stuff is usually included in the tax bill (sometimes as a specific item); liquid waste disposal is covered in your water and sewer bill. In Ottawa, my hometown, it costs roughly $1.64 per day.
Now, home heating: what waste is involved in that?
If you use any of the first four fuels in the list above, the waste is mostly carbon dioxide (CO2), the main man-made greenhouse gas. And how much CO2 comes with each of those fuels? In terms of CO2 content per kilowatt-hour of heat:
- Light fuel oil (number 2): 253 grams of CO2 per kilowatt-hour. Enough to fill six 20-litre water jugs.
- Natural gas: 188 grams per kWh. (A cubic meter turns into 1,879 grams of CO2 when burned, and there are roughly 10 kWh in a cubic meter of gas). That would fill five 20-litre water jugs.
- Propane: 212 grams per kWh (NOT the 72 grams I originally stated; that was an error). You buy propane sometimes by the litre, and sometimes by weight, but each litre, which contains 7.13 kWh, and turns into 1,510 grams of CO2. That is 38 water jugs’ worth of CO2. Each kWh of energy from propane comes with enough CO2 to fill 5 jugs.
- Wood: 302 grams. (See U.S. EPA Compilation Of Air Pollutant Emission Factors (AP-42) document, Section 1.6 “Wood Residue Combustion in Boilers.”, table 1.6-2) The waste CO2 from each kWh would fill eight water jugs.
Those quantities are pretty much fixed. If you want heat from any of those fuels, then their carbon content is the same for every kWh they produce (there is an efficiency factor; I will deal with that in a second).
Now, how much energy do you use? An 8-kilowatt (~27,000 BTU/hr) furnace might on a cold day run for 40 minutes every hour. Over a day like that, the furnace will run for 16 hours. So total energy use for that day would be 16 hours x 8 kW = 128 kWh.
So you need 128 kWh of heat over such a day. What are the “waste” implications across the range of fuels given above?
- Light fuel oil: 128 kWh x 253 grams of CO2 per kilowatt-hour = 32.38 kilograms of CO2. That would fill 79 55-gallon oil barrels.
- Natural gas: 128 kWh x 188 grams = 24 kilograms of CO2. That would fill 59 55-gallon barrels.
- Propane: 128 x 212 grams = 27.1 kg (NOT the 9.2 originally stated). 66.4 barrels.
- Wood: 128 x 302 grams = 38.7 kg. 95 barrels.
These figures assume perfect efficiency in the contraptions in which the fuel is burned. Perfect efficiency is physically impossible with such contraptions. Exhaust gases must exit the home, or the inhabitants will quickly die. Those gases contain some of the heat of reaction. Which means that the CO2 amounts just quoted are understatements.
That CO2 gets dumped not into a landfill nor down a drain. It goes into the great garbage dump we refer to as our planet’s atmosphere. In the atmosphere, it acts to trap heat energy. Rising levels of CO2 have caused rising surface temperatures on the planet. This has led to climate change, which is the greatest environmental threat facing mankind.
This is why some people think we should pay for the CO2 we put into our air. Maybe if we pay for it we will dump less of it.
So—let’s put a price on it. Let’s say it should cost say $100 per metric ton. A lot of people think that is high, but my hometown of Ottawa Canada charges $104 per ton at the local landfill. And garbage is garbage, right?. So let’s just see how it would impact the cost of heating on that one cold day.
Here’s what that one day of heating would cost:
- Light fuel oil: 32.38 kilograms of CO2 x $0.10 (yes, ten cents) per kg = $3.23, for 79 55-gallon oil barrels’ worth of waste.
- Natural gas: 24 kilograms x ten cents = $2.40, to dispose of 59 barrels of waste.
- Propane: 27.1 kg x 10 cents = $2.71, for 66.4 barrels.
- Wood: 38.7 kg x 10 cents = $3.87, for 95 barrels.
So you would add that amount to the cost of the fuel, and that would be your cost of heating with fossil fuel.
Now, let’s say you heated with electricity, instead of one of those carbon-based fuels. Unlike the fuels above, electricity’s CIPK is variable: it depends on what sources are feeding the grid that delivers power, and on the time of day. In Ontario so far this year, the CIPK of grid electricity has been 44.63 grams.
So: 128 kWh of electrical energy x 44.63 grams = 5,713 grams = 5.7 kg.
And 5.7 kg x 10 cents = 57 cents.
Ontario electricity kWhs are cleaner by far than the cleanest of the combustible fuels above (14 oil barrels’ worth of CO2, versus 59.5 barrels for natural gas). Not only that, Ontario electricity waste would also be cheaper from the carbon price viewpoint to heat your home.
Ontario’s grid CIPK could and should be lower than 44.63 grams. It could, and should, be zero. It could be zero if we added more nuclear plants. See Table A1 in the upper left of this page. It shows which sources are feeding the grid, and which ones are producing the current CIPK. Of the sources that have a zero in the “CO2, tons” column, nuclear is always the biggest and most constant.
As for waste, don’t worry about it. The cost of nuclear waste disposal is already included in the rate we pay for nuclear electricity. That is because there are roughly 3,500 kilowatt-hours of energy packed into these little pellets.
This means that the waste from releasing enough energy to power 384 typical homes, day and night, for 100 years is contained in each of the white casks shown in this photo.