Calculating Your CO2 Footprint Part 2: Getting to 1.6 Tons CO2 Per Year Per Capita


George And His Wife's Current Daily Drivers

George And His Wife’s Current Daily Drivers

Have you calculated your CO2 footprint yet?

In the first part of this series we used a simple method to calculate the author’s CO2 footprint.

Rooftop Solar In Play

Rooftop Solar In Play

As shown in figure 1, the author is relatively “green” by today’s standards.

He and his wife drive a Volt and a Prius, even though he lives in hot Arizona he has no A/C bills due to seasonal change of residence to the mountains. He also has a 3 kw Solar array on his roof in the desert house where he resides 7 months of the year. While he is gone in the summer, the solar system cranks out kwh’s and saves them in a kwh bank account at his utility to be used when he returns in October.

Figure 1

Figure 1

The author should have a pretty low CO2 footprint right?

Wrong. The calculation showed that, even though he is a factor of 4 below the current US footprint, he is still a factor of 2 above where he needs to be by 2050.

Figure 2

Figure 2

Figure 3

Figure 3

Fully 44% of his CO2 footprint is from electricity generated by the grid…..even though the Arizona grid is in line with the US average.

The author has charted a path toward achieving the 1.6 ton CO2 bogey. The plan is simple…..just attack the major sources of CO2 in his footprint.

Figure 4

Figure 4

The plan for lowering his CO2 footprint is shown in figure 5. The major thrust of the plan is switching to a pure BEV from the Prius and cleaning up the grid by switching coal fired plants to natural gas.

Figure 5

Figure 5

The plan is broken into 2 steps. The first step is switching from the Prius to a pure BEV and cleaning up the grid by switching coal fired plants to natural gas.

Figure 6

Figure 6

In order to calculate the state average power plant emissions, one must first know the present mix of power plants in the Arizona. We can see in figure 7 that Arizona gets 40% of its electricity from coal.

Figure 7

Figure 7

We assume the coal plants are brought into compliance and recalculate the state average. Even though we reduced coal plant emissions by nearly a factor of 2 by switching to natural gas, the state average decreased by only 30% as shown in figure 8.

Figure 8

Figure 8

Using the step1 mix of power plants decreased the author’s footprint from 4 tons CO2 to 2.8 tons CO2. As explained earlier, switching from the Prius to a pure BEV and decreasing heating emissions by switching to a heat pump instead of burning propane were also part of step 1.

Figure 9

Figure 9

We see from figure 9 that the step 1 plan decreased the author’s footprint from 4 tons to 2.6 tons, failing to meet the 1.6 ton bogey. Further improvements are required.

The next step was to calculate how much cleaner the grid would need to be to get to the 1.6 ton bogey. Calculations showed that another 30% decrease in power plant emission would be required bringing the total improvements including step 1 to 60%.

Figure 10

Figure 10

In summary then, what needs to be done to get the author’s footprint to the 1.6 ton bogey?

Figure 11

Figure 11

Getting the grid cleaned up to this degree is a major obstacle to this plan. The EPA proposed rules are not enough to get us to 1.6 tons

Figure 12

Figure 12

What power plant mix would be required to clean up the grid by 60%?

Figure 13

Figure 13

First, all new natural gas plants must be combined cycle power plants. Combined cycle offers a significant improvement over conventional natural gas plants as shown in figure 14.

Figure 14

Figure 14

The other big component in the grid mix is an increase in zero carbon electrical sources as shown in figure 15.

Figure 15

Figure 15


Is the 1.6 ton bogey attainable by 2050?

Probably not.

Figure 16

Figure 16

Bottom line……..the grid needs to be cleaner than the new EPA guidelines. EPA Guidelines for Arizona are .702 lb/kwh as shown in table 3-1 of the EPA proposal by 2030 versus .465 lb/kwh shown in this presentation.

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69 responses to "Calculating Your CO2 Footprint Part 2: Getting to 1.6 Tons CO2 Per Year Per Capita"
  1. Anderlan says:

    14,210W? I was like “That doesn’t look like 14kW, it’s only 14 panels.”

    No need to put a comma between the 14 and the 210. If more clarity is needed nothing says you can’t write it as “Fourteen 210W panels.”

  2. Anderlan says:

    Why should we have to do all this work? Penalize the damned carbon emissions! Government doesn’t have to collect any more money, but simply use the revenue to give us an extended broad and equal tax holiday. You can’t tell me that getting revenue from income and work is better for us than getting it from pollution.

    (Of course you can if you’re an evil person that makes money off pollution, but I’m asking normal good people).

    1. kdawg says:

      Higher prices for energy would curtail use by customers.

      1. Ocean Railroader says:

        That is one thing I hate is the idea that we can tax our way out of our problems. Such as in my case my power company is all coal and natural fired so my bill would go though the roof. And my power company being the way they are would much rather have the coal shovel taken from their cold dead hands then go renewable. What this means is they would jack up our rates to the stratosphere.

        Adding taxes for carbon are a joke in that they kill jobs. Along with that India and China are building ten times more coal fired capacity then we thought possible. So adding a tax on US power would send more bleeding jobs over to India and China were it’s a free for all.

        1. kdawg says:


          Prices go up, usage goes down, competition occurs.

          What if prices creeped high enough that it became feasible/profitable for a renewable energy company to do business there? What would the existing energy companies do? Just stick to their principals & coal, or would they try to compete? If they chose the former, then feel the wrath of the market, and go bankrupt.

          1. Jay Cole says:

            We are definitely seeing the cost splits between ‘old school’ and renewables narrow as they become more widely adopted (thanks to scale) and as technology further reduces costs/increase efficiency. (especially in solar)

            The cost of finite resources will continue to rise, both due to increasing scarcity/difficulty to access in relation to a growing population; and just keeping in line with inflation itslef (no tech/scale to offset inflation when you are talking coal)

            The answer to a cleaner grid may just be the passing of time and a commitment of the public and gov’t to continue to promote/expand renewables.

            1. kdawg says:

              Things will get really interesting if/when Solar City builds their Gigafactory in NY.

              1. Ocean Railroader says:

                Well my current energy independence plan calls for me getting a EV in the next few months. And then a year or two after that I plan to get some solar panels with a small battery back up system.

                I’m waiting for the Giga Solar panel factory in that it will push prices down a great deal. There is also something else at work here. When ever I visit the solar panel websites it’s not uncommon to see a lot of the stuff they have price cuts of 10% to 20%.

                1. Josh says:

                  The 30% investment tax credit for solar is set to expire at the end of 2016, so don’t wait too long on the PV install.

        2. Anderlan says:

          We should get more revenue from pollution, and less revenue from income and work. Until pollution is reduced to a remnant. To disagree is to say that getting revenue from work and income is somehow better for us.

          This is an old and obvious concept. It’s such a no-brainer that I think people come on forums just to pour water on it on behalf of the fossil companies.

          EVERYONE who has a big brain in this arena has posited it.

          Here’s Elon saying it:

          Here’s Art Laffer (conservative economist icon, father of the Laffer Curve):

          1. pjwood says:

            +1, +Ingles (former SC Rep), +British Columbia’s method

      2. Anderlan says:

        Not “energy”. I hate that. If we mean “fossil energy” we should say “fossil energy”. Remind people that there’s a new world of non-fossil energy and it’s ready and waiting to take over. It’s the heir apparent and the old king is killing the country. People who don’t breathe this stuff actually forget that unless you remind them.

    2. Spec9 says:

      Yep. We just need that revenue-neutral carbon fee. That would get people to clean up their act when they realize that they can make/save money from being more efficient and adopting green energy systems. It is a financial gamification of atmosphere protection.

      1. sven says:

        Only if the US can imposed a carbon fee on imported goods, otherwise you’d encourage manufacturera to offshore production to countries without carbon fees.

    3. no comment says:

      one of the problems in the US is that energy usage is not taxed at anywhere near a high enough level to change energy usage behavior. no politician would be willing to propose such because it would be career limiting. the crazy arguments that you get are that such moves are “job killers”; well, when this environment goes to hell in a hand basket, it will result in both *job* killing and *people* killing. there is already evidence that Miami will go under with rising sea levels as flooding is already becoming more common in the area. how many jobs will that kill?

      president obama is absolutely correct in calling for a focus on new energy technologies. yes, there will be some inconvenience to move to new technologies and there will be job dislocations as has always happened in technology shifts. if existing power companies refuse to change as “Ocean Railroader” suggests, then new companies will eventually take their places. the article “marketing myopia” described how companies and even industries can render themselves obsolete if they refuse to change (the article dealt with the railroad industry in particular, but you get the idea).

  3. Kosh says:

    “There is no way we will ALL be driving EVs in 40 years”….

    where do statements like this come from? Don’t see it quantified anywhere in your study.

    Do you have a crystal ball?

    1. kdawg says:

      Based on the life of current cars, and the state of and availability of the technology. For example, other than VIA Motors, who has an EV truck for sale right now? If Tesla makes one in the next 10 years, that means any trucks bought 10 years from now will still have a 20 year life. That’s 30 years. And this is if 100% of the people switched to electric trucks in 10 years. Even if they wanted to they couldn’t since VIA & Tesla would not have the ability to provide all of them.

      Elon Musk has made this same observation several times during interviews/conferences.

      1. Ocean Railroader says:

        What’s really a driving factor if we will be all driving EV’s in 40 years is if low income and poor people can afford them in the next five years. As of now I think it’s possible in that the price of used EV’s has gone down a great deal recently.

        1. kdawg says:

          Most low income people buy used. That means all of the middle/upper income population would have to be driving enough EV’s for there to be enough of a used EV market. It’s not going to happen in 40 years, no way.

          Not saying we won’t make significant market penetration, but as soon as someone uses words like “All” or “Never”… all bets are off.

          Something to consider is that plug-ins have been available for 4 years now and have just reached about 0.08% of new sales. Look how long hybrids have been around and they are only at ~4% of the market.

          It’s just going to take time. And more time than 40 years, due to the nature of cars. If it was cell phone technology, no problem.

          1. Ocean Railroader says:

            Acutely it’s going on right now that there is a large enough used car market for low income people like me to get a EV. In that the used 2011 leafs and used 2012 Mitsubishi i-mievs regularly go below $12,000 on the used car websites. In fact I plan to buy one in the next few months due to this happening. What’s also cool is you can watch the average prices drop every few weeks.

            1. Assaf says:

              Ha, just looked at used Leaf prices on Seattle Craigslist last night.

              The average 2011 asking price seems to be just under $15k, 2012 around $17-18k. Dealership sellers will finance, too.

              @kdawg: you are 10x off in your market-share calculation. The current US plug-in market share is 0.8%. Note that this includes all light truck sales, even though plug-ins don’t really compete in that segment. For passenger cars we are now over 1.5%: 12k out of 700k. Not shabby in my books.

              IMHO the biggest hurdle right now is to build up capacity and expand the variety of nationwide offerings. You can’t expect everyone to love the Leaf, afford the Model S / i3, or understand what the Volt is 🙂
              It’s no wonder one of the biggest growth paths has been those Ford Energi. Just keep it simple and normal.

              1. kdawg says:

                That was a typo (got it correct below).

                Even still, I don’t think we’ve jump the chasm just yet.

                link to full pic:

                1. Assaf says:

                  Nice chart.

                  The Volt doesn’t seem to have yet made the leap towards pragmatists – but both the Leaf and those lowly PHEVs do seem to make inroads into that segment.

                2. Josh says:

                  Haha, did you add Fox News out there to the right?

      2. Kosh says:

        Not sure I agree with you on that. I don’t really see that many 40 year old cars on the road. Maybe 30 (from the 80s) driven by teenagers.

        I think the turnover will happen faster than you thinking given the operating cost incentives.

        1. kdawg says:

          Not saying there are tons of 40 year old cars out there. The life of a car is about 15 to 20 years. Because of this length of life, even if EVERY SINGLE vehicle purchased today was an EV, it would take 20 years to have 100% market share. Note the current market share for plug-ins are 0.8%. That’s not 8%, but less than 1%. 40 years is just not enough time.

          My crystal ball whispers in 40 years we will be lucky to get up to 20% of the cars on the road being plug-ins. There’s 300 million vehicles in the US, so that would be 60 million plug-ins.

          I’m hope we will blow past this, but don’t want to get my hopes too high.

        2. sven says:

          Don’t forget about the the large percentage of people in the US that live in dense urban areas and have no access to a plug now, nor will they in the next 20 years.

    2. alain says:

      in 20 years from now ,most will be driving bev ,and everybody will have solar panels ,they are only getting cheaper cheaper , I wouldn’t worry about 2050 but more the next 10 years !today is the right time for both !we are already there ,people just don’t Know yet! it going to be a big wave ,you just can’t see it yet .

  4. Aaron says:

    Drive less. I drive <7500 miles a year; my wife drives <5500 miles a year.

  5. kdawg says:

    How about turning down the water heater temp? That should save on some natural gas.

    1. GeorgeS says:

      Both houses have electric water heaters on timers.

      1. kdawg says:

        I was just speaking in general. Something people could do to reduce energy use.

        1. pjwood says:

          The heat pump water heaters cut use in half, without changing temperature. 4,500 watt heating elements are THAT inefficient.

  6. Andrew says:

    Wow no flying at all, impressive! That’s one of the hardest things to give up. Where is the accounting for the other house he lives in 5 months of the year? Also why not ride a bicycle? Also food and trash should be accounted for.

    1. GeorgeS says:

      A lot of people are commenting about all the sources I have left out like flying just to name one. Of course those are valid points that just make my calculated emission go UP when they are included. That is why I said in the last chart the 1.6 ton bogey is pretty difficult to obtain.

      It just point to the enormous size of the issue we are dealing with.

  7. Blind Guy says:

    Pssst, hey George, how are you going to talk your wife into trading in her beloved Prius? That technique might be as helpful as lowering ones’ carbon footprint.

    1. GeorgeS says:

      ha ha Richard. So true. Pretty difficult to get her to do that. There’s no way in reality that it can happen now anyway. Part of the problem is her miles are fairly long distance commutes to Phx from either Pine or Tonto Basin. The only EV that can do that is a Tesla and we can’t afford that.

      1. kdawg says:

        Sounds like you need another Volt.

  8. Warren says:

    I searched, but can’t find sales numbers for zero turn lawn mowers. But my observation is growth has been exponential since the crash. I see them everywhere. These things have the weight and power of a 2CV to cut lawns that used to be done with a push mower, by high schoolers. They are now being cut by laid off boomer “entrepreneurs.”

    1. Ocean Railroader says:

      I think in 40 years the oil will decline so bad that we are going to have hundreds of millions of EV’s sold or hundreds of millions of gas cars taken off the roads of the world. We might even have 1970’s and 1940’s style world war two gas rationing. If anyone thinks I’m crazy about this idea. The way oil markets work is you only need a decline of 20% to 30% to trigger something like this in that growing oil demand would soon find itself dealing with a 20% smaller supply which would really drain things.

      1. Spec9 says:

        It is always extremely difficult to make predictions on this but I think it will happen much earlier than 40 years in the future. Probably less than 15 before we start having significant decline issues.

        1. zoe-driver says:

          The russian TASS says: Decline of oil production starting 2016.

          BTW Mexico is already in decline for years and US shale is expected to start decline in 2016 as well.

          Europe had Peak-Oil in 2001 and is now producing just 53% from 2001 amounts.

          My Guess: Be prepared for something starting in 2016 …

          1. Ocean Railroader says:

            That is one of the reasons why I’m going to get my first EV around late 2014 to early 2015. In that I think around 2015 we are going to see the return of $4.25 a gallon gas at the the least even if it’s the middle to the end of the year.

            The main thing that worries me now is it’s not a case if I can get a EV to stay on the road. But should I wait the extra year to get one with double the range. Or should I buy a cheap used one and put in a bigger battery a year or two later or when my commute needs a bigger battery?

  9. Bob A says:

    Would it be reasonable to consider atmospheric carbon removal in your calculations?

    How much net carbon does a tree remove in a year? Are there other plants that could do it better?

  10. Assaf says:

    Thanks for the nice post.

    How much CO2 is your natural-gas home heating (so I gather from your post) estimated to be responsible for?

    Ours is natural gas too. It’s probably time to replace it – either this fall or next.

    1. GeorgeS says:

      It’s shown in figure 2. I use 300 gal propane in a year. That’s 3810 lb CO2=1.9 Tons for the 2 of us.

  11. TomArt says:

    Holy crap – a VAST majority of US households only have ONE domicile – if you want to reduce your carbon footprint, SELL one of them! Sheesh…

    1. GeorgeS says:

      That would increase my CO2 footprint. The seasonal change keeps me from having to run any A/C.

      1. Warren says:

        A Mitsubishi mini-split heating/cooling heat pump, as used all over the world, if run off solar PV is cheaper, more efficient and has lower CO2 than any system you can get. Surely this would be better than a second house.

  12. Mark H says:

    Some good places to start George is Harmon and Quadrafire. As Surya mentioned, either decide whether you want a pellet boiler located external to your home or in a basement, or a free standing or fireplace insert. Also research what options you have for buying pellets by the ton in your area. All pellets are not equal either. Low ash content and BTUs matter. You can heat your entire home with a 40,000-50,000 BTU insert if you don’t mind stratification of your heat (cold rooms far from the heat source). This is helped by running the fan on your current central house system.
    You can easily heat a 2000 sq ft area for about $500 a season AND reduce your carbon foot print.

    1. GeorgeS says:

      Thx for the input Mark H. I’d do a fireplace style, preferably with a water heater insert. We have a lot of people in Pine that use them and the pellets are readily available but I haven’t checked prices on pellets yet.

  13. Lindsay Patten says:

    George, can you elaborate on why more solar isn’t an option? You mentioned the rate structure in the comments of the previous article but didn’t explain.

    1. GeorgeS says:

      I’m glad you asked.
      The answer will not pertain to most people.

      The desert house has the 3 kw solar system. We leave to go the the mountain house in May and return in mid October.

      During the summer the solar system cranks out kwh’s into the utility since it is grid tied.

      The way Arizona Public service has the system structured I have to use the banked kwh’s up before the end of the year so I have 2.5 months to use them up. If I don’t use them all up (I usually don’t) then APS pays me a wholesale price for what I haven’t used.

      In the old days they payed me 7 cents /kwh. (My retail rate is around 12 cents/kwh).

      However they have now lowered the rate for buying them back to 2.6 cents which is a rip off.

      If I add panels to my solar system then I just have more excess kwh’s at the end of the year to sell back at rip off prices.

      1. GeorgeS says:

        So then why not sell one house as others have suggested?

        If I sell the mtn. house then my kwh consumption goes up by a huge amount in the desert house probably negating all the panels I could add.

        If I sell the desert house I’m stuck in the mtns. 12 months a year and solar PV won’t work up here because of all the trees.

        1. Lindsay Patten says:

          I don’t suppose you have a neighbor that is close enough to sell your excess electricity to at, say, 11.5cents/kWh?

          Our roof is almost completely shaded which has made me ponder installing panels on a neighbor’s roof…

          1. GeorgeS says:

            He’s threatened to come over and plug in for free when I leave. (actually he’s a good neighbor it was all in jest)

          2. pjwood says:

            I think they call that ‘Virtual net metering’. Lots of states are running against the caps utilities set on how many solar watts their utilities had to buy, by law. Most utilities don’t have to go much beyond 5% of their peak instantaneous daytime load. In MA, it was 4%, and we just had to give up VNM in order to make it unlimited. So, no free market for your watts, despite the low transmission cost to your neighbor.

            It will all accelerate the solar + battery storage adopters further within the window of time that the power co’s know they need to recover cost on major new plant investment. This battle is being fought on many fields, state by state.

        2. RussB says:

          If you sell one of the houses, you would get a huge credit for allowing someone else to avoid building a new house (assuming it is not bought by someone as a second home). As it is, you should add to your footprint your share of the manufacturing(and end-of-life) impact for both houses. And the cars, and the solar panels, etc.

      2. Mark H says:

        You are not thinking “red neck” enough. What I would do is, get a really nice compatible racking system at both locations. I would transport my panels bi-annually. There are nice nylon separators that will allow you to stack a 5kWh system in the back of any pickup.
        Such a solution would not work for everyone, but you can do this in a couple of hours.

        It helps to picture you George going down the road in a pickup with the theme to Sanford & Son playing in the background. =)

      3. SIvad says:

        By 2050 you will have no problem adding more PV panels to allow you to be off grid anyway. And thanks to large battery pack advancements from a growing EV market, long before 35 years from now battery backup systems will be small enough and affordable enough to store energy for days.

        Finally to seal the deal of being off grid, you can install a backup generator for that 1-5% of the time you might need it. You can already get a 7kw NG generator installed on a pad and hooked up to your standard NG line for a few thousand dollars.

      4. pjwood says:

        George, I don’t know APS, but Salt River Project’s (the pub util) average wholesale resale rate was exactly 2.61 cents/kwh, in FY13.

        Arizona is pretty lame. You also have a flat fee, to net meter, like $15/mnth? Maybe that is coming. It’s frustrating that the “sun math” of AZ can be so good, but in reality low priced power states can really slow down adoption.

  14. zoe-driver says:

    Very good article. Peeple start thinking about that. Good. BTW Germany had record of 31% renewables in 1H/2014. PV and Wind allone delivered 17% of all produced electricity. The train is moving, no one can stop it. Things are getting cheaper and sexy.

    1. sven says:

      Does the 17% of electricity produced by PV and solar come close to replacing the electricity Germany used to produce CO2-free by their nuckear plants before they were shut down?

      1. zoe-driver says:

        Hi Sven,

        the 8 AKWs been shut down 2011 just produced 5% of all electricity in Germany, easily covered by now 17% of PV and Wind. Our Goal is to have 80% renewables by 2035. We do not want to be dependent from other countries and we do not want the risk of extrem expensive nuclear power plants. And it can be done. 31% of renewables is remarkable. The electric car ist one small piece in the big puicture. How much renewables does the USA have ?

  15. sven says:

    George, you could always have or adopt a couple of kids to lower the per capita carbon footprint of your household. 😉

  16. pjwood says:

    AZ is going to be an interesting state to watch, if the EPA rule sticks. Most walk around with the “30% of 2005 CO2, by 2030”, as a national blanket statement. It’s actually different for each state. For AZ, EPA has in store CO2 reductions of 46-52%, if that state does not submit its own plan (SIP). That’s benched to the electric side, in 2012, and it suggests the grid has gotten a lot more CO2 heavy, since ’05. What it says about solar may be ‘hang in there’. The state also has its own renewable target, and a growing population of solar owners will probably find better voice with/against the state commission.

    It sounds obvious, but solar is now an actual industry in the U.S. That is beginning to make a huge “jobs, jobs, jobs” difference, at state houses, and in DC.

    If I sound like I don’t care where the cost of energy goes, consider Austin energy entered contracts in Q1, to buy hundreds of acres of solar output, for ~5 cents/kwh. Rince, lather, repeat. They are a public utility, where making noise can make more of a difference.

  17. no comment says:

    one of the premises of this article is that two houses are needed to reduce carbon footprint because if he stayed in one house year round he would use more energy. this is an unpersuasive argument.

    there is a whole area of building science that is concerned with the construction of low energy usage houses. these include passive houses and zero energy buildings. for a passive house, for example, primary energy use should be less than 38k BTU/sf/year. as you would expect, a zero energy building is one with a net zero use of energy. ironically, while the leadership in these technologies comes from Europe, the origin of these technologies traces back to work done at the university of Illinois in the 1970’s. then they were referred to as “low calorie” houses; there was some work done in the U.S. and Canada in the 1980’s but interest here faded. in the late 1980’s a person named dr. wolfgang feist (in Germany) picked up on this work and developed the Passivhaus concept.

    i would challenge anyone to go to your local window store and inquire about purchasing triple glazed windows. first of all, the salesman is almost certain to not know what you are talking about. then he’ll probably tell you that the extra cost isn’t worth the energy that you would save. the same is true with solar panels, which can have 20+ year payback periods. all of this could change if the U.S. changed its tax policy to make energy usage much more expensive. this would motivate people to use more efficient energy technologies, where the motivation is not present today. thus, “greenies”, or people who attempt to use less energy as a matter of conscience, are a bit of a social oddity – create an economic motivation through tax policy and “greenies” will become more the norm.

    1. pjwood says:

      I picked up some custom interior storms 3 weeks ago, from this place. Awesome with noise, not just energy:

      …of course, since this thread is now a couple days old, it won’t do him much good, but its a nice business (~$200 per glazed storm).