In the same week Google revealed the environmental profile of its Gmail service, the search engine giant also released details of its overall corporate environmental performance the year 2010.
According to Google, it recorded a total of 1,457,982 metric tons of CO2 equivalent for the year 2010. This includes 11,126 metric tons of CO2e for direct emissions (Scope 1) from cars, company shuttles, onsite fuel consumption at its offices, 1,226,350 metric tons of CO2e of emissions from purchased electricity (Scope 2), and 207,065 metric tons of CO2e from other indirect emissions (Scope 3) such as business travel, commuting, manufacturing its servers, building its data centres, and consumption by leased premises. The overall figure also includes 13,441 metric tons of CO2e from a new category – Biogenic emissions, from landfill gas combustions.
Overall, that equals about 1.46 kg of CO2e per user (employee) on an annual basis, Google said. Google adds that without its energy efficiency measures at its data centres, its footprint would have been “about twice as big.”
In addition to the overview of its carbon footprint, Google also gave further details of the energy profile and performance of specific areas of operations.
For example, it says that its data centres now use only 50% of the energy of most other data centres. This, Google says, saves it “millions of dollars in energy costs and cuts our impact on the environment.”
And the savings don’t stop there because Google also buys carbon offsets, in addition to buying and generating renewable energy (30% of Google’s energy in the year 2010 are from renewable sources), so any amount of energy saved, and carbon avoided, also means it needs to buy less carbon offsets to achieve its carbon neutral status.
Another interesting figure from Google is what percentage of global electricity its data centres consume. Based on a study by Standford consulting professor Jonathan Koomey, who estimates the global data centre energy consumption at between 1.1% to 1.5% of the global electricity consumption, Google says that its figures equal only about 1% of the Koomey figure. So 1% of 1.3% (as the average of the Koomey estimate) puts Google’s data centre electricity consumption at 0.01% of the global total, the company said.
CO2 and web searches
Now for the fun part. As part of its carbon disclosure, Google also revealed a very interesting fact – that each 100 web query uses up about 20 grams of CO2. That, according to Google, equals about the same energy as operating a 30W laptop for an hour, keeping a 60W light bulb on for 28 minutes, or the energy needed to produce 1.5 tablespoons of orange juice.
With that figure however, we can now estimated how much CO2 we all use for web searches on a daily, or annual basis.
My calculations as follows:
- 100 searches = 20 g CO2
- Google searches in June 2011 (comScore) = 11.1bn
- 11.1/30 days = 370m Google searches/day
- 370m/100 x 20g = 74 million grams, or 74 metric tons
- 74 metric tons x 365 = 27,010 metric tons a year from Google searches.
So there you have it. The world generates about 74 metric tons of CO2 per day conducting Google searches. On an annual basis, that’s 27,010 metric tons, or roughly one fifth of the CO2 from Google’s purchased electricity.
Applied the same formula to comScore’s total number of web searches in June 2011, and the result is 112 metrics of CO2 per day, or some 40,880 metric tons of CO2 every year.
So what does 40,880 metric tons of CO2 mean?
According to the EPA, that equals the same emissions from about 7,000 passenger cars in a year, about 4 million gallons of gas, and about the same amount of CO2 needed to generate electricity to power 4,500 homes in the US for a year.
Obviously, the figure doesn’t include the energy used by the PCs and increasingly mobile devices that are doing the searching. While coming up with a realistic CO2 profile of the Web is nearly impossible at this point, at least we know have a pretty good idea of the energy profile of one of the more popular components.
Lastly, Google also revealed the CO2 profile of YouTube – 1 minute = 0.1 g, or 3 kg over 3 days. Anyone want to calculate how much CO2 we all use watching videos?