Blog Post

The Carbon Calculator Morass

In the process of looking into carbon calculators for buildings as a behind-the-scenes assistant for the EBN feature article "Counting Carbon: Understanding Carbon Footprints of Buildings," I took a short detour into the wider carbon calculator world. While construction calculators may still be rare, the Web offers a multitude of general carbon calculators for businesses and households and also specialized calculators for everything from wineries to land remediation activities. It seems everyone is getting into the act — utilities, environmental groups, oil companies, government agencies, and offset providers (especially offset providers) are all offering up their own calculators. These vary widely in their approach, scope, level of complication, rigor, transparency, visual appeal, and results — including what aspect of household or business operations is the greatest contributor to total emissions. The primary value of these simple calculators is getting people thinking about the issue and providing some motivation for change, but the system should at least be accurate enough to help users develop a reasonable sense of priorities for action. The ideal calculator would provide default values using average data while allowing users to improve the results by providing their own actual data on utility bills (including gallons, therms, kWh, not just dollars), vehicle fuel efficiency, miles driven, flights taken, and other behavioral characteristics. The ideal calculator would also provide tips for next steps, and allow users to track efforts over time, as well as test the likely impact of different strategies. Even better would be if you could dig behind the displayed answers and see what all the assumptions were underlying them — a major bonus for geeks like me. EBN did not attempt a comprehensive review of lifestyle calculators, or comparison of results (especially once we realized what a rabbit hole we'd be entering). A little browsing on the web shows how many others have tried variations on that theme — and how hard it can be. Also, new calculators pop up daily. The calculators below are just a few that we thought rose to the top while wandering through the morass of options. For a more in depth review (though still by no means comprehensive) try Consumer Reports' review of travel results, the Home Energy Saver table outlining the scope covered by a range of calculators, or check out the Earth Charter Initiative's list of calculators available by country. We'd love to hear of any truly thorough reviews you know of, or what calculators you think are best. A few notable calculators in the mix are the following:
  • Low Impact Living's Environmental Impact Calculator, which provides a comparative assessment of a range of impacts, not just carbon emissions; suggests actions; and lets users save and update their profiles. (In contrast, the Ecological Footprint Calculator has an animated custom avatar, but I'm not convinced it provides much life-changing value.)
  • The CoolClimate Carbon Footprint Calculator, which considers a wider range of activities at a detailed level. Inputs include what users eat and purchase as well as the more typical questions about the user's house, based on expenditures, and comparison with national and "similar household" averages. The calculator was developed by the Berkeley Institute of the Environment (BIE), at the University of California, Berkeley).
  • Safe Climate Calculator, by World Resources Institute, which is short and asks only the hard numbers: therms, kWh, fuel economy and miles traveled, and rewards you at the end with a little animated guy who becomes a devil or angel depending on your emissions.
  • TerraPass, like most if not all carbon offset providers, has a suite of calculators, including personal and business calculators as well as specific calculators for driving, flying, etc. Also typical, the only option to "take action" is to buy carbon offsets or other "green products. " None of these are designed to encourage behavioral change. Still, I liked that it allows users to input specific flights taken, rather than number of "short" or "long" flights, or total miles or hours traveled. This doesn't mean TerraPass's calculator is more accurate, while that is possible — all I know is it shows the lowest emissions on the Consumer Reports review, and I'd lean towards using one in the middle of the range in the absence of better info on accuracy.
  • EPA provides a whole suite of calculators themselves (including ones for waste, recycled content and durable goods), and links to other's calculators — but what is especially useful for folks trying to get the word out is their GHG Equivalencies Calculator — which lets you input a consumption unit and get out how that number compares to barrels of oil consumed, tree seedlings grown, passenger vehicles, etc, etc. With this you can put emissions into terms anyone can understand.
What's next? Well, it looks like we'll be getting calculators like the "Carbon Hero" that calculates a user's carbon footprint from transportation as you move around, carrying the tiny data-collector with you. While I'm not sure whether this is really any better a calculator, I'm pretty sure it'll appeal to the gadget-geeks (but, we also need a hand-held one that calculates the embodied and operational carbon of each gadget they purchase). Unfortunately, the most noticeable thing about carbon calculators is still the plethora of options and the lack of consistency amongst them and we will applaud all efforts to clarify the field. In the mean time we still think trying out some of these calculators is a worthwhile effort to get people thinking, but we suggest taking the results and recommendations with more than a grain of salt.

Published June 18, 2008

(2008, June 18). The Carbon Calculator Morass. Retrieved from https://www.buildinggreen.com/blog/carbon-calculator-morass

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Comments

BuildingGreen Basic Member

August 13, 2008 - 11:19 am

We already have a building carbon calculator that is very transparent, can list the assumptions you make and spits out consistent tonnage based on some general building data. I think it is the only one currently written. Unfortunately, it was funded and therefore written for the UK building types and climate. I am working on a US model at this point in time, but am in the early stages. The version on the web is very basic, entering three building parameters; you can also download a protected copy that gives many other opportunities to modify input assumptions. Any comments appreciated. http://www.fgould.com/uk

BuildingGreen Basic Member

June 18, 2008 - 5:28 pm

The coolest calculator on the web is for air travel. At http://chooseclimate.org/flying, you can use the cute cursor to plot your trip, enter your aircraft type, class of service, passenger load factor, and get the results in fuel and GHG emissions. You can also find out how your trip compares to an annual budget for sustainable GHG emissions, that is, a global per capita average that is estimated to produce a stable climate. You will find out that GHG emissions in aircraft are roughly 3x as climate forcing as ground level emissions, partly because of where they are injected and partly because of the water vapor emitted.

ASHRAE is working on a project to develop a calculator for building designers and operators that allows the use of simulation data or real monitored energy use to see the impact of design and operational alternatives. Time of day, season, weather, and location make a lot of difference. Energy use has different GHG emission implications as a result. So evaluating trade-offs requires understanding the total and marginal emissions on a time and weather dependent basis. We are working to develop that tool and now have a description of the project that will result in the tool. All we are lacking is the funding. Checkbook handy, anyone?

BuildingGreen Basic Member

July 1, 2008 - 7:29 am

A calculator that links energy to carbon that is not listed here, but should be(!) is
AMEE: a neutral aggregation platform to measure and track all the energy data in the world. It is a web-service (API) that combines measurement, CO2 conversion, profiling and transactional systems. I don't work for the creators of it, just think its really well done, and definitely needed. See: http://www.amee.cc

BuildingGreen Basic Member

July 5, 2008 - 2:21 pm

Regarding carbon credits, what I am seeing is that people are now using them as an excuse to continue living the way they have been, but feeling better about it because they can offset their bad habits by purchasing credits. The awareness that has been raised since the Kyoto Protocol is valuable, however; is it backfiring for the everyday consumer? Some of my clients tell me that they are planning a holiday (as usual) and are flying (as usual), have booked a resort (as usual) and have offset the trip by purchasing carbon credits, so they feel really green. I think the carbon credits are great at creating the awareness, though a strong next step is needed. How does one police those purchasing credits randomly to absolve their sins? Is education an even better way to make people aware that change is more important than offsets? This conundrum sits with me at this time and I have no ideas for solutions. Do you?

BuildingGreen Basic Member

July 5, 2008 - 9:37 pm

Eileen has posed the major moral dilemma of our time. I confess to being as guilty as the next person in spite of my "heightened awareness." I fear that short of regulations and taxation, reducing carbon emissions is still a ways off. One hopeful sign is that most major corporations are aware of the issue and many are actually taking steps to identify and reduce their carbon footprint. Governments are acting too, but perhaps too meekly and slowly. The presence of carbon labels on cars is about to happen in California, but when cars are carbon neutral, then consumers can make the "right" choice. Now cars are promoted as "green" that are half as fuel efficient as the more fuel efficient ones on the road. The awareness is rising, and that is the first step toward change. Let's hope it doesn't take too long or it may not be enough.

A humorous rendition of Eileen's comment is Cheat Neutral, a clever spoof on carbon offsets created about a year ago. It is very entertaining albeit terribly sad. You can see it at www.cheatneutral.com. They describe it thus:

What is Cheat Offsetting?
When you cheat on your partner you add to the heartbreak, pain and jealousy in the atmosphere.
Cheatneutral offsets your cheating by funding someone else to be faithful and NOT cheat. This neutralises the pain and unhappy emotion and leaves you with a clear conscience.

Can I offset all my cheating?
First you should look at ways of reducing your cheating. Once you've done this you can use Cheatneutral to offset the remaining, unavoidable cheating

BuildingGreen Basic Member

September 5, 2008 - 6:13 pm

After you have read the EBN article on buildings' carbon emissions, you will want to stay tuned for the public release of a project just completed by Energy and Environmental Economics (E3) of San Francisco for the California Energy Commission -- "Developing a Greenhouse Gas Tool for Buildings in California: Methodology and Use." It is a carbon emissions calculator based on California data (only) and using dispatch software rather than historical data. But it will show the users how much difference alternative design and operational strategies make in terms of carbon emissions that don't always map one-to-one with energy consumption due to the different sources of energy at different times of the day, week, and year in California. It provides both marginal and total carbon emissions results. It is not tuned to the weather conditions that give rise to different energy consumption in buildings and, at least in the case of hydro, different sources of energy with different carbon emissions implications. There are plans to post the spreadsheet on the E3 web site so that anyone can use it or at least play around to get a feel for what it is like to use electric energy at different times of the year or to make trade-offs between on-site combustion and electricity generation or to substitute conservation or energy efficiency measures for supply options.

Another project completed by Synapse Energy Economics in Cambridge, MA, -- ANALYSIS OF INDIRECT EMISSIONS BENEFITS OF WIND, LANDFILL GAS, AND MUNICIPAL SOLID WASTE GENERATION. It is based on historical data for 2005 for the entire country and gives hourly emissions for all regions of the country. Again, it is only for that one year and is not necessarily applicable to any other weather year. It shows that for some regions of the country, using an annual average value can distort the annual total carbon emissions by as much as ~60% while in other regions, there is little difference between an annual average value and an annual total based on 8760 hourly values. You can download a copy of the report from http://www.synapse-energy.com/Downloads/SynapseReport.2008-07.EPA.EPA-In...

We (at ASHRAE) continue to work on developing a tool that will combine the best features of both of these projects in the ASHRAE project committee, and hope to issue an RFP to address some of the unanswered questions about the uncertainties associated with the alternative approaches to developing the emissions database that would be necessary for the ultimate tool we want to develop for use with popular building energy simulation software. Our present task is to revise it into a Work Statement for funding by ASHRAE. We are awaiting news on a possible project to be funded by DOE to develop data for use in a building carbon emission calculator before finalizing our Work Statement. We hope to submit the project for approval by ASHRAE's Research Advisory Committee at the Winter Meeting in Chicago in January.