A carbon footprint, on the other hand, measures the volume of greenhouse gases released into the atmosphere. Like our ecofootprint, Canada also has the third highest carbon footprint in the world: 24 tonnes per person. By comparison, the UK is 11 t/pp while China is far behind at 2 tonnes per person. Per year. A more comprehensive carbon footprint not only measures immediate emissions, but the life cycle of a product. Instead of measuring only the electricity that we use to prepare our food, an extended carbon footprint would also include the energy used in the production of the food and its delivery to market. The earth's ability to absorb carbon is fast declining. Scientists estimate we have already overshot it by 30%. The oceans are close to saturation; forest cover is decreasing and fertile soils are eroding. Our lifestyle exceeds the sustainable limits of the biosphere. Our ecological debt is surging. We are no longer living off nature’s interest; we eating up our scarce biological capital.
In September 2005, the (now cancelled) One-Tonne Challenge program assessed our home carbon footprint at 3.4 tonnes of greenhouse gases per individual occupant, just over half the national average and well below the Kyoto target of 4.5. After the changes we describe below, using the same carbon calculator, it came in at about 2.5 - a reduction of more than 25%. Our home's ecological footprint in September, 2005, was 4.3 hectares per person. The latest calculation puts us at 3.5 hectares per person, slightly less than half the national average - a 20% reduction.
We have passed global peak productions in oil, fish and food and we have reached the physical limits of fertile land, freshwater and clean air. We are also close to a tipping point in atmospheric concentrations of greenhouse gases and face irreversible climate change.
Furthermore, statistical footprints cannot measure some of the less discernible damage we are inflicting on natural ecosystems. We are choking the oceans with plastic, poisoning our lakes and rivers with chemical toxins, and contaminating the subterranean water table with leachate from our garbage dumps. The extinction of countless species is unraveling the complex web of life underpinning human survival.
Curbing Consumption: The First Step Towards Sustainable Living
"Be the change that you wish to see," said Gandhi. There are no technofixes that will reduce our environmental footprint while keeping our consumer lifestyle. Changing our behaviour is far less expensive, (though more difficult) the only approach that will ensure a sustainable future for the planet, just as conservation is far cheaper than consumption. It is time for the real conservatives to stand up.
For the past 4 years, I and my wife have been engaged in a personal quest to reduce our energy consumption and greenhouse gas emissions, to demonstrate that the targets in the Kyoto Protocol and in the (sadly defunct) One-Tonne Challenge are attainable without sacrificing quality of life.
We live in Ottawa (a cold city) in a 19 year old, 1800 square foot townhouse. We started with an energy audit of the house, which gave us a mere 66% energy efficiency rating. Most of the loss is through windows, doors and roof. Other hard-to-find exterior heat losses, such as faulty wall insulation, were located with an infrared scan. The audit took baseline readings of utilities' energy consumption, for post-refit comparison. Our home was one of the first in Ottawa to install a digital smart meter, which allows us to check how each step reduced consumption.
Armed with baseline readings, energy audit, and recommendations for improvement, we were ready to start. Focussing on low tech energy conservation, we:
- replaced bulbs with compact fluorescents
- installed rain barrels
- installed low-flow showerheads and toilets
- sealed air leaks
- gradually replaced old windows
- put in a wrought iron front door
- awnings on south facing windows (we do not use air conditioning)
- overhead ceiling fans
- an indoor drying rack in stairwell (Dumbarton air dryer, see photo)
- reshingled the roof with light shingles, and
- reinsulated and ventilated attic space.
Food consumption: we try to buy produce from a 100 mile radius by shopping at local organic markets and by tending our own vegetable garden in the summer. We reduced our consumption of meat. A locavore vegetarian diet could cut our eco-footprint by as much as 30%.
In addition to energy-saving, we reduced our ecological footprint by almost eliminating garbage disposal -- by minimizing all purchases, recycling and composting biodegradable material. We are down to one small bag every 6 months. We also shop second-hand when possible. All products contain embedded energy (carbon emissions, processed water-- a cotton shirt, for example, has a water footprint of 2,00 litres!). Second-hand shopping is a good way to practise an important environmental R, “re-use.”
The next step
We also bought an inexpensive watt meter to measure individual appliances. Appliances using 220 volts that are wired directly into the panel require a more advanced meter, such as “The Energy Detective” which must be installed by an electrician. All appliances contain embedded energy used in the manufacturing process -- so simply replacing a relatively new fridge, for example, might not be a wise decision, financially or environmentally. Another decision involved the cost of new appliances. Bill Kemp, a renowned Ottawa area energy efficiency specialist, explains the concept of life cycle cost, which he calls “true cost” as opposed to “first cost” (or initial cost) in his book Smart Power: An Urban Guide to Renewable Energy and Efficiency. He argues that basing the purchase of appliances on their energy efficiency and buying quality (and, often, more expensive) products when upgrading will actually outperform the stock market in the long run. We have tried to apply the concept of life cycle costs to all our purchases. Already we can see a return on investment as resource and energy prices continue to rise.
Pursuing these principles, we gradually replaced our major appliances and car with:
- a high efficiency natural gas furnace.
- efficient dish and clothes washers.
- a small 25-gallon electric hot water heater
- a natural gas cooktop
- a small electric convection oven.
- an energy recovery ventilator
- an airtight woodstove
- a smaller barbeque, and
- a Toyoto Prius.
Our electricity consumption is now only 375 kilowatt hours per month, compared to the Ontario average of 750-1,000 kwh/m (varying with number of occupants, and use of electricity for space and water heating -- we use lower-cost natural gas). Because our electrical water heater is small, set at 49 degrees C and our showers and appliances are low-flow, power demand is not quite low. For two people, we use half the provincial average.
We need no air conditioning in summer. A screened wrought iron door allows cool night air to circulate through the house; fans and awnings keep the house comfortable during the day. We cook outdoors on a small barbecue or a two-burner hotplate to minimize indoor heat buildup. On smoggy days, we eat cold plates and salads because coal-fired electricity and barbecues both contribute to particulate emissions. Replacing energy-hog dryers, we use an outdoor drying rack for clothes in the summer, and the indoor rack during the winter.
To trim our carbon emissions even further, the Robertsons have signed on to renewable energy from wind and low-impact hydro at marginally higher prices from Bullfrog Power. Because so much of Ontario’s electricity is still coal-fired, this substantially reduces our carbon footprint.
In winter, our home is heated by a high efficiency natural gas furnace, complemented by a low emission airtight wood stove. We also use a gas-fired cooktop in the kitchen. Together with improved insulation, reduced air leaks, our consumption of natural gas 900 cubic meters/year and dropping steadily. The Ontario household average is 3,000 cubic meters for water and space heating alone!
Our water footprint is down to 80 litres per person per day because of rain barrels, efficient appliances and low flush toilets. The daily Ottawa consumption is 250 litres per person; the national average is about 300. More than half the City’s operating budget is spent on electricity charges to pump, clean and distribute water and then remove and treat wastewater and sewage. Imagine how happy citizens would be if their city taxes were cut by one-third!
Three years back, we replaced our 13 year old Volvo with a hybrid Prius. Our gasoline consumption has dropped by two-thirds. This and no repairs have saved us at least $3000 per year, helping to offset the capital costs of the Prius. The initial cost of $30,000 is more expensive than many cars in the family sedan category. But based on life cycle expenses, Consumer Reports recently rated the Prius “least expensive” car in this category.
Driving is still the largest part of the our carbon emissions. They are not proud of the fact that they average 25,000 kilometres per year, slightly more than the national average. The high mileage is partly for family reasons (“love miles” in the words of George Monbiot, author of Heat) and partly because they avoid flying for environmental reasons. We are all too aware that driving accounts for half of the carbon footprint of Canadians who own a vehicle.
Our first energy audit rated our house at 65 out of 100. Minor refits improved it to 72. Further improvements have now pushed its rating to 79, qualifying us for Energy Star status. We came within a whisker of the R2000 level of 80. If our 18 year old townhouse can be transformed into virtually an R2000 home, why are we as a society not demanding construction of energy efficient houses? Retrofitting is a more expensive way of improving efficiency and fighting global warming than new-build. Approximately half the greenhouse gases created by each Canadian are generated in the home.
Return on investment - sunlightelectric.com
How cost effective are retrofits and renovations? What is the cost recovery period? These are legitimate questions for homeowners. Our improvements were done gradually, as regular maintenance, upgrading substandard workmanship, or replacing worn out appliances or. We had no major capital projects, such as installing solar panels. Over the past 4 years we have spent about $30,000, partly financed by government rebates and dramatically lower utility bills. We have established our own carbon fund to offset the emissions of the Prius. We use these “carbon dollars” for our energy-saving projects. Real estate consultants advise homeowners to set aside 5% of the value of the house per year for maintenance -- such as Energy Star doors and windows, and energy efficiency. Last year we had to replace the roof shingles. We chose a light colour, to reflect sunlight during the summer, thereby reducing heat build up in the attic and keep the house cooler. Our roof shines out clearly on Google Earth. At least we are safe from a heat seeking missile!
A recent CMHC study shows most home renovations are undertaken for cosmetic reasons. These may no longer enhance the resale price of a house, as resources become scarce. In the UK, the law will soon require that home sellers get an energy audit. Energy efficiency rather than cosmetics may soon determine home prices. So retrofit and energy-conserving appliances make both economic and ecological sense. Improvements will increase the value of a house, both short and long-term. Monthly utility costs, paid in after-tax dollars, are reduced and generally our homes are healthier and more comfortable. Unlike other possessions, homes are free of capital gains taxes when sold.
Our upgrading costs over the past 4 years were $30,000 for home improvements and $30,000 for a Prius. Neither of these expenditures is excessive by current standards for renovations and vehicles. We estimated the cost recovery periods home, appliances and car at between 3 and 12 years. But rising energy and resource prices may well shorten these periods. For us, money was not the main motive – moderating climate change by reducing our footprints may be the most rewarding result.
We do not live like ascetics. In winter, our thermostat is set at 20 degrees during the day and 17 at night. We also run an Energy Recovery Ventilator which circulates fresh air but recaptures the heat from the outgoing air. Our energy and carbon savings have not imposed a dramatic change in quality of life. So it is doable, by ordinary people. We can live more sustainably at no great cost or inconvenience. Individuals can make a difference in the battle against climate change.
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