Thursday, June 18, 2009

Carbon Footprint, Carbon Savings and Carbon Offsets

All resources are finite. As humans our resources consist of money, time, passion and energy. In the end, where, how and when we deploy these resources will determine our comfort and happiness with our lives. While there are some basic truths, the optimal allocation of your resources is based on your values and goals. We all should be thoughtful in our living, smarter about the ways in which we use the earths and our personal resources.

According to McKinsey and Co. it cost an additional $30-$40 above normal energy production costs to eliminate one ton of CO2 emissions by replacing traditional energy production with solar or wind power (the presumed life of the equipment was unreported). However, when a ton of CO2 was saved using LED light bulbs or energy-efficient appliances money was also saved ($108-$159 less was spent on energy for every ton of CO2 saved). The costs associated with generating power without CO2 emissions are higher than current costs. If the money is spent to reduce CO2 by replacing generating capacity there will be less money to spend on other things that matter to you or are necessary for your life, but if you reduce the use of energy less money is spent on energy and more money is available for other goals.

When you use less energy, by insulating, changing to lower energy light bulbs, controlling passive solar heat, or using energy star appliance, less energy is used, less CO2 released and money is saved. Reducing your energy consumption is a far better utilization of resources. While solar panels and wind turbines are sexy, and renewable sources of energy sound wonderful, these technologies are still in their infancy. Geothermal generation of heating and cooling and nuclear generation of power have failed to catch on in the United States, but have advanced significantly in the past few decades in overseas locations. Conservation and energy efficiency are currently well developed technologies, effective and relatively cheaper. Use less so that we can all live within the productive capacity of the existing infrastructure. Then only expand the generating capacity in ways that do not release CO2, do not burden the earth.

Adding insulation and sealing existing homes and commercial buildings is by far the low hanging fruit and a good source of “green economy” jobs. The Wall Street Journal reports that heating and cooling buildings account for about half of the CO2 emissions in the U.S. My home was built in 2004 and is heated and cooled with a duel system; the upstairs with an air heat pump and the lower levels with a gas furnace and air conditioner. Replacing the heating and cooling systems with geothermal systems would only make sense when the existing systems reach the end of their functional life. After eliminating incandescent light bulbs, upgrading all appliances to energy star, installing reflective films on the window and installing drapery, I found that adding insulation was a good way to further reduce the energy consumption of the house. Following the recommendations of the Building Envelope Research of the Oak Ridge National Laboratory the attic, crawl spaces, eves, duct work, underside of a large portion of the main level floor were insulated with cellulose. The pipes, end caps, knee wall, sump pumps and all identified areas were sealed, the garage was insulated and an insulated garage door installed. After six months electricity usage (as measured in kilowatts for the same six months the previous year) had been reduced by over 6% (despite relocating our workspace to the home with all its attendant equipment) and the winter liquid propane usage (as measured in volume use December through March both years) was reduced by 25%. Also, the overall comfort in the bedroom over the garage and the master bedroom has been vastly improved. I was very surprised (and pleased) at the energy savings for what was a well insulated home.

Though I do not need to commute to a job, I still drive my (gas hybrid car) almost 4,000 miles a year. The hybrid does not make economic sense especially because I drive so little. However, it does make me happy to drive so to me it was worth the extra money I paid for it. In searching for the carbon emitted per vehicle mile I could only find the 1993 data from the Nowak study which lists 0.88-1.06 lbs CO2 per mile. This is probably high for my hybrid, which was not available at the time of the study. The same article states that each person in the US generates 2.3 tons of CO2 each year, which appears in conflict with the automobile numbers until you realize that babies and children do not have cars and city dwellers automobile ownership and use is also much less than suburban use. During the eight years I lived and owned a car in the city, I drove less than 1,000 miles a year. After reducing the energy use in my home, eliminating commuting from our lives, reducing frivolous travel I still wanted to do more.

I found the following fact: “A single mature tree can absorb carbon dioxide at a rate of 48 lbs/ year and release enough oxygen back into the atmosphere to support 2 human beings.” The Tree Folks are the source of the above information, and are willing to sell carbon off-sets in the form of trees. I tend to think of carbon off-sets for people who want to vacation in Bora Bora or have the wedding or Oscar party of the century, but in truth they are probably for people like me who use various technologies to make their lives richer and happier. My large house comes with a big piece of land. Admittedly, most of the land is wooded undisturbed land and part of the Chesapeake Bay water shed, but I do have about 3 acres of mostly open land around the house. We planted 43 trees of moderate maturity (over 6 foot each). Using the Tree Folk data, forty-two trees absorb a ton of carbon a year and the last tree replaces a diseased tree we cut down. Beyond watering the trees in the first three weeks they were planted, they have thrived on benign neglect. I am already drawing up plans, researching native trees, and saving my nickels for another 3.6 tons of annual carbon off-sets otherwise know as another 150 trees. I may have to make that 152 trees because there are two more existing trees that are not doing well.

Trees can also reduce air conditioning and heating needs by providing shade and providing a wind shield for winter. Trees also act as natural pollution filters. Their canopies, trunks, roots, and associated soil and other natural elements of the landscape filter polluted particulate matter out of the flow towards the water shed and use nitrogen, phosphorus and potassium which are contributing factors to the decay of the Chesapeake Bay water shed. Trees are pretty.

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