# Two More Carbon-Footprint Calculations

posted earlier about my first carbon-footprint calculation attempt, on carbonfootprint.com and thought I’d try another couple calculators to see how they compared.

First, I tried The Nature Conservancy‘s calculator. They gather a lot less detailed information than carbonfootprint.com, but also ask some new questions, like how often I check my truck’s air filter and tire pressure. They also have a way to be clear that I’m getting my individual carbon footprint, not that of my household, which was not so clear with carbonfootprint.com. They calculated my carbon footprint as much bigger than carbonfootprint.com, though, at 17 metric tons of CO2 per year: 17.8% on home energy, 64.6% on driving and flying, 2.8% on waste and recycling, and 14.9% on food and diet.

They also provide an opportunity to offset my entire carbon footprint and calculated the cost for me to do was \$255: \$15 per metric ton. That’s pretty cheap. I’ll have to look into carbon offset schemes and see if they are convincing.

Second, I tried footprintnetwork.org. They try to calculate how many planet earths it would take to support a population living my lifestyle–an interesting way of thinking about it. They gather a lot of the same information as the other sites, like how local is my food and how much I fly and drive. In some areas they gather more details, like how often I eat each of several kinds of animal products, how often I buy new clothes, furniture, appliances, and computer gear, and what kind of siding my house has.

This site estimates that if everyone lived like I do, we would need 3.5 planet Earths to sustain us. They suggested several ideas that would decrease my footprint: .1 of an Earth if I half my animal product consumption, .2 of an Earth if I “pledge to use less packaging,” .1 of an Earth if I use public transportation once a week, and .1 of an Earth if I do not fly this year because I chose “a local vacation.”

If I did all of these things we would need only three Earths to sustain us all at my standard of living. Half of an Earth’s savings is nothing to scoff at, but doesn’t really get us there. Plus, I already use very little packaging, and do not often fly for vacations.

They estimate how many “global acres of the Earth’s productive area” my lifestyle requires:  7 acres “energy land,” 2 acres “crop land,” 1 acre “grazing land,” 2.5 acres “forest land,” .5 acres “built up land,” and .25 acres “fishing grounds.”

They also calculate my “ecological footprint” percent by category: 52% in services, 11% in goods, 12% in mobility, 4% in shelter, and 16% in food.

Something is wrong about these calculations, but I’d need more details to know what. Half of my land-use is for energy, but half of my footprint is in “services.” What are these services that are using so much energy?

Still, a picture emerges. I have estimates of 10.41, 13.7, and 17 metric tons of CO2 per year, approximately 3-5 times as much as an ethical target. I probably create the most CO2 by burning fuel, driving and flying.

(This post was originally published here on Nathen’s Miraculous Escape.)

# A Quick Foray Into Carbon Footprint Calculation: 10.41 Metric Tons of CO2

(Reblogged from Nathen’s Miraculous Escape, from June 15, 2012.)

On a challenge from the blog 400 Days ’til 40 I did a quick-and-dirty calculation of our carbon footprint for a year here in California. I just used the top hit on Google for “carbon footprint calculator” and made my best estimates for all the values they asked for:

1. I live in California, USA, in a household of two.

2. I use no natural gas, heating oil, coal, LPG, and no net electricity by virtue of a solar array, thanks to an investment by my father. Reanna and I cook with propane, and a little research is leading me to believe we will go through approximately 50 gallons in a year, maybe less. Our share of the firewood that my parents burn for heat in the evenings is about .4 of a cord. My share of all this contributes .08 metric tons of CO2 per year.

3. I fly to Portland and to Albany every year to work at Not Back to School Camp. That contributes .95 metric tons of CO2. Something like a quarter of a ton for each leg. Pricey!

4. Car travel is the biggest polluter at 5.05 metric tons of CO2. This amount probably varies quite a bit each year and is way up from my Eugene, OR lifestyle. This estimate includes a few trips to town each week, a dozen trips to the LA area, and one long road trip to Canada. That’s a bit less than 2 tons for each of those kinds of commutes.

5. I use a significant amount of bus and train travel on my business (and some other) trips as well, adding about .12 metric tons of CO2.

6. The second biggest polluter is a group of “lifestyle” choices. 1.21 tons for eating animal products, 1 ton for owning one car, .5 tons for eating only “mostly” local produce, .61 tons for buying stuff with packaging, .17 tons for buying “some” new equipment, .41 for throwing some stuff away, 1 ton for sometimes going out to movies and restaurants, and .4 tons for having a bank account. Total = 4.21 metric tons of CO2. (The highest value possible here was 24.53 tons.)

Here is the summary they gave me:

• Your footprint is 10.41 metric tons per year
• The average footprint for people in United States is 20.40 metric tons
• The average for the industrial nations is about 11 metric tons
• The average worldwide carbon footprint is about 4 metric tons
• The worldwide target to combat climate change is 2 metric tons

I have plenty of questions about and criticisms of the way this calculator works. They ask my household size first but do not indicate if they are calculating my individual footprint or my household’s. That could change my score quite a bit if I’m taking the blame for Reanna’s share.

I’d like find a calculator which takes into account more specifics, too. I have owned the same car for 20 years, for example, but the way they asked the question gave me the same carbon footprint as someone who has a brand new SUV every year. Miles driven, too, is not as important as number of gallons of gasoline burned (see my mileage/fuel tracking project here). I buy some things with packaging and I throw some stuff in the landfill (see my landfill tracking project here), but “some” is a vague category to hang such a precise 1.02 metric tons of carbon on! What about grass-fed versus industrially produced meat?

On the other hand, two metric tons is a pretty tight carbon budget, and finding a more accurate calculator will not likely shift my score dramatically. And with this calculator, I am at 520% of my two metric tons, this with a relatively low-profile lifestyle for an American. I could come down to 222% if I did not own a car and never drove one. If I also stopped eating animal products and stopped going to movies and restaurants, I would be close, at 112%. If I also stopped flying, I could actually come in under budget, at 64%, leaving some slack for others.

That’s a pretty discouraging proposition! The biggest barrier is the isolation. No travel means never seeing a large part of my family and community. And the idea is that kinds of lifestyle choices would have to become the norm, not just the domain of eccentrics….

# A Couple Things About Gas Mileage

(Reblogged from Nathen’s Miraculous Escape, from May 28, 2012.)

I heard a segment recently on NPR about gas prices and it reminded me of the link between driving speed and gas mileage. According to the story, driving over 60 miles per hour is equivalent to paying \$.25 more per gallon for each five miles an hour faster. So if you paid\$4.00 for a gallon of gas, but burn it at 65 miles an hour, it’s like having paid \$4.25. Seventy miles an hour makes it \$4.50, etc.

It seems funny that it’s very easy to imagine Americans complaining about the price of gas, but very difficult to imagine them driving the slightest bit slower in order to save that same money. In fact, I can easily imagine an American burning a 70-mile-per-hour gallon of gas to go out of their way to save \$.25 cents per gallon at the pump. (It could be a good economic decision to do so, I suppose, depending on how many gallons of gas you need to buy, and how much your time is worth, but it still seems funny.)

If I remember my physics correctly, I think the loss of efficiency is actually not that linear, that a 75-mile-per-hour gallon probably costs significantly more than the \$4.75 that NPR’s equation predicts. It has to do with the amount of force each particle of air hits the front of our car with–it’s the same principle we (if we are from the desert) use to remember to drive slowly or stop during a sandstorm, to save our windshields from getting sandblasted. Any physicists in the audience care to explain the mechanics of it?

In his excellent lecture “Climate Change Recalculated,” engineer Saul Griffith tells about how he gave an intern this incredibly boring job: Drive his wife’s Honda Insight in 100 mile stretches around a runway at constant speeds, twelve 5-mile-per-hour increments from 20 to 75 miles per hour. Seventy-five miles per hour was the worst, obviously, at about 40 miles per gallon, and the most efficient speed, at about 85 miles per gallon, was 30 miles per hour.

That’s pretty slow, but three times as fast as the average driving speed for large urban areas, he points out. I’ve been thinking about making my next trip to Portland at 30 miles an hour, to see how little gas I can use to get there. It’ll take 4 hours to get there, so I’d better bring some good company.

# Buying Local? Consider Biking to the Store

(Reblogged from Nathen’s Miraculous Escape, from April 8, 2012.)

In a part of the new Seminar About Long Term Thinking, “Deep Optimism,” Matt Ridley talks about the ethics of buying local. Apparently, the amount of fuel used to ship an object to a store in the US from a factory in China is on average ten times smaller than the fuel you use to drive to the store to buy it. There are other factors in the ethics of buying local, of course, but it may be that how you get to the store is a more important decision than how far away the object you want was made or grown. It makes me wonder where buying mail-order falls in terms of fuel efficiency. Will we see Amazon asking us to buy from them to protect the planet?