(Editor’s note: This article is written by entrepreneur Salman Farmanfarmaian and researcher Shui Bin. They point out the massive amount of carbon emissions the U.S. IT sector is creating abroad, something that is almost entirely overlooked by the current debate among G8 nations about how to tackle global warming.)

Venture capitalists and technology companies, from Google to Yahoo, are playing a prominent role in pushing environmental initiatives.

But most of these efforts tackle the carbon emitted within the United States – from our cars, in our homes and in local oil wells and power plants. Much less attention is being paid to so-called “embodied emissions” – the carbon emitted by manufacturing plants worldwide to produce the goods we import into the United States.

Take your laptop computer, for example. Chances are that some of its components were produced in a country like China, using energy from a coal fired power plant there. Yet, when we buy a laptop, we don’t usually think about all the carbon emitted so far-away from us by the power plants that provided the energy to make all the parts that went inside it. Since that ‘embodied’ carbon is emitted ‘out of sight’, it is easy to keep it ‘out of mind’.

We decided to estimate the total amount of carbon that was emitted outside the United States (ie ‘out of sight’) to make all the IT, telecom and consumer electronics we import into the United States. We did this with the help of the Economic Input-Output Life Cycle Assessment model (www.eiolca.net), an environment and economic model developed at Carnegie Mellon. The carbon emissions ‘embodied’ in those imports can be calculated based on their trade values, the carbon emissions coefficients of producing the same products in the US, and the purchasing power parity and fuel structure of the import countries, relative to the US. (The estimates reported here assume that the import countries have the same purchasing power parity, fuel structure, and technology levels as the US. If things like purchasing power parity are adjusted, emissions estimates may increase. Our data and methodology notes can be found here.)


Here are the critical numbers: The US imported $84 billion of computers and related equipment in 2006, and an estimated 66 MMTCO2 (million metric tons of carbon dioxide) at least were emitted outside the US to produce these products. These emissions are said to be ‘embodied’ in those imported products. If we include imports of semiconductors, and consumer electronics (including electronic components and audiovisual equipment), then the relevant numbers are $261 billion of imports embodied with 151 MMTCO2. The total embodied emissions have grown almost three fold in the past decade. This increase is due to the 66% growth of the dollar value of imports over the same period, together with the decrease in the price of the goods. (ie we are buying more electronic goods with the same dollars.)


To put this data in perspective, it might be helpful to compare the embodied emissions to the total carbon emitted in the State of California in 2003 (the most recent data available to our knowledge):

The computers we imported into the United States in 2006 were embodied with an estimated 40 MMTCO2, just a little less than the 42 MMTCO2 emitted by all electric power generation in the state of California in 2003.

If we include all computer and data storage equipment, then the embodied emissions of the imported equipment goes up to 66 MMTCO2, or 50% more than the annual emissions in California from electric power generation.

The emissions embodied in all imports of IT and telecommunications equipment (including audiovisual equipment, semiconductors and related components) were 151 MMTCO2 last year – that is roughly two thirds of the 228 MMTCO2 emitted by transportation in California.

The emissions embodied in all those imports are 3.5 times more than all emissions from electric power generation in California, and 5 times more than the 28 MMTCO2 of annual residential emissions. Or, from another perspective, the emissions embodied in those imports are also roughly equivalent to the reported annual emissions from all passenger cars in California.

We are comparing the emissions embodied in US imports to the emissions in the State of California so as to contrast the relative attention paid to these two sources of carbon emissions. Ultimately, whether we drive a car to work or we buy a laptop, we are effectively contributing, directly or indirectly to global carbon emissions. Yet, tremendous efforts have gone into curbing direct emissions from local sources in California. Our estimates of the amount of carbon emissions embodied in imports suggest that more attention should be paid to understanding their impact.

California also provides an interesting point of comparison because of the pivotal role it plays in setting trends and standards in the technology and consumer electronics industries. If California IT and consumer electronic companies took steps to address these embodied emissions, there can be little doubt that the rest of the industry would follow suite. As such, we expect that Californians have tremendous leverage in influencing and addressing this problem if they choose to.

So what can they do? They can ask local companies to take a lead and go deep into their supply chains to reveal the total amount of carbon emitted to produce the goods they sell. Britain’s supermarket chain, TESCO has announced the goal of doing this. Computer and electronics companies should consider doing the same, and label each of their products (including your laptop) with the total amount of carbon that was emitted in producing them, whether the associated carbon was emitted domestically or not.

This story was co-written by Shui Bin, a researcher at the Joint Global Change Research Institute.