Monday, April 26, 2010

Earth Day and Carbon Offset Credits

I promised more tech talk in the end of last week's posting. This will be "tech-lite"!

Earth day has come and gone and, judging by the amount of coverage all things green are getting (from consumer products to industrial and enterprise practice), things are looking up for good ol' Mother Earth. Of course, we all know someone who got stuck in Europe by the big belch of a volcano in Iceland ... so we will never be quite as clever about all this as we think.

We just completed a calculation of our lab's carbon footprint and will now buy carbon offsets for that amount as part of our efforts to "incentivize" ourselves to reduce our footprint. Of course, the actual control we have in our lab,  comprised of some rooms in the first floor of a six story building (with one big on-off switch for the HVAC that we cannot control) sitting on a campus with one large power meter measuring the campus energy, seems small on first glance. But, we do travel, use lights and machinery, buy consumables for experiments, so we are not without some ability to change our impact.

In the August 10th, 2009  posting (see we had an extensive discussion about footprints and some on-line tools for calculating them. Our strategy for calculating our lab's footprint is more analytical.

We presented a scenario of how we do these calculations and why at a recent campus open house for the public and I will summarize this here. Josh Chien, one of the researchers in the lab, worked this up. (I gave a link to a you-tube video of his presentation with all the details in the last posting - see; narrated by his girlfriend!). I will be quick to acknowledge that our lab (a few thousand square feet of space, some 20 researchers (and their travel), a couple of nice machine tools and other processing hardware, computers, instruments, espresso machine, desks and furniture, computer projector, etc.) is not Wal-Mart. But it is probably close to a large number of small businesses. This is more like the calculation a "department" in a large corporation would do. We did not include our share of the general campus infrastructure we use in our daily operation.

We define carbon footprint as a collective measure of one’s environmental impact, in particular, direct and indirect greenhouse gases (GHG) produced from creating and sustaining human activity; typically, represented as global warming potential (GWP) with units of metric tonnes (or kg) of carbon dioxide equivalent (MTCO2e).

We calculated this using a hybrid economic input-output life cycle analysis (EIOLCA). I discussed this approach in a recent posting ( and we applied it to a manufacturing example in the last of the greening the supply chain postings two weeks ago.

The hybrid-LCA approach was used to determine our carbon footprint with respect to four sectors:
- embodied energy (lab equipment and food)
- electrical energy (direct emissions from our local utility, PG&E)
- steam energy (lab heating and hot water)
- transportation (commuting to lab and business trips)

The EIOLCA GWP database by Carnegie Mellon University is a source for data that represents U.S. average, see for an excellent discussion and data source.

Now for some details.

Embodied energy refers to the energy and resources consumed during the raw material extraction, manufacturing and transportation phase of a product - the output is indirect GHG emissions measured in MTCO2e, or embedded GWP for an item. This can be calculated as: item cost ($year) × EIOLCAGWP (MTCO2e/$year) = GWPembd (MTCO2e). For example, for the desks in our lab

Electrical energy refers to the power consumption of a product during its use phase - the output is indirect GHG emissions measured in MTCO2e. This can be calculated as: power (kWh) × Costelec ($/kWh) × EIOLCAGWP (MTCO2e/$) = GWPelec (MTCO2e)

or, if the mix of your local utility is known,
 power (kWh) × GWPPG&E (kgCO2e/kWh) = GWPelec (MTCO2e). For example,

Steam energy refers to the energy required to generate steam for heating and producing hot water - the output is indirect GHG emissions measured in MTCO2e. We can calculate this for our building and then, lacking any more specific data, apportion it to our lab based on our percentage of the floor space in the building.

Finally, transportation refers to the energy required for a transportation mode - the output is direct GHG emissions measured in MTCO2e. This is calculated, for land travel (none of us commute by boat!), as mpg × distance (miles) × emission (GWP/mile) × days/year = GWPtrans (MTCO2e).

We use the following conversion factors for land-based transportation (including BART, our local subway):

- gasoline: 8.9 kgCO2e/gal
- diesel: 10.2 kgCO2e/gal
- BART: 0.06 kgCO2e/mi

For air travel, usually to and from conferences and meetings, we use an online calculator from Climatecare (see to estimate the impact of travel. It considers length of travel, etc. Everyone lists their business and commuting related travel for the lab calculation. Not surprisingly ... I am the biggest contributor to this one!

Now for some results. Our total GWP for 2009: 175.43 MTCO2e is comprised of the following amounts from the four components:

- embodied energy: 120.70 MTCO2e
- electrical energy: 15.50 MTCO2e
- steam energy: 2.31 MTCO2e
- transportation: 36.92 MTCO2e

The importance of "location" is brought home in the computation of our electrical energy consumption and it's CO2 equivalent. The figure below shows a comparison of our impact using our "local" utility (with a very renewable mix of energy sources) with the equivalent data from the EIOLCA website referenced above. This EIOLCA data reflects the US average. PG&E uses much cleaner and more renewable energy than the U.S. average.
Clearly, it is a big advantage, in our case, to use the more accurate local data. And, once again, it shows the importance of location in your supply chain impact calculation.

Now, what to do about this? We have chosen to purchase carbon offsets from, a leader in providing carbon offsets (, to "offset" out the GHG impact of our lab. Any individual, business or organization can purchase carbon credits, equal to their carbon footprint, thus offsetting their carbon impact and becoming certified carbon neutral.

Carbon credits can be used to help fund renewable energy, reducing overall energy demand, reforestation & avoided deforestation and many more. The assumption, and you need to verify this, is that the money you spend for the credits you purchase goes to the intended purpose of carbon reduction or capture in the amount you paid. This is, to me, an "unregulated" market so one wants to be sure the organization one purchases the credits from has some track record.

in 2007, LMAS became the first UC Berkeley lab to become carbon neutral and offset 415 MTCO2e with We missed last year. Our footprint of 175 MTCO2e this year is substantially reduced from the first year we did the calculation. This is due to, primarily, the initial footprint of all the embedded existing hardware, furniture (ie non-consummables) in the lab.

What about the cost? There are many helpful websites comparing the cost, and benefits, of different sources of credits. One good one is On that site you'll see that, for, the cost of a one metric ton of CO2 equivalent credit is $10.00. And, importantly, you can see what the funds are used for - in this case Renewables, Efficiency, Reforestation. It also indicates and certification the organization has for its "product".

In the case of Carbonfund, they are certified or verified by Environmental Resources Trust, Climate Community and Biodiversity Standards, Chicago Climate Exchange, UNFCCC JI. The site gives links to the websites of these organizations. Other categories of carbon credit sources, some for which they could not find certification or verification are shown as well. It also says that businesses can often get a "volume discount" or carbon offset credits!

So, whether or not you decide to do this for your organization, it is an interesting exercise. The Carbonfund website has a built in calculator but part of the "fun" is doing it yourself.

I feel better already!


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