Servers and data centers run around the clock, and every click causes carbon emissions. We calculate the carbon emissions of your website and invest in climate protection projects as compensation for you. Automatically and without additional costs for you.
Our calculations are based on the idea of the API of Website Carbon. However, we have revised and rewritten the code for our own purposes to enable an even more accurate calculation of carbon emissions.
Calculating the carbon emissions of a website is not easy and can never be 100% accurate to the emissions. Nevertheless, there is enough knowledge to calculate the value correctly in the order of magnitude. To do this, we use five data sources to give a good estimate:
- Data transmission
- Energy intensity of the web data
- Energy source of the data center
- Carbon intensity of electricity
- Website traffic
Data Transfer.
When a website is loaded, the energy consumption is roughly proportional to the amount of data transferred.
To calculate the amount of data, take the five most visited pages and their proportions of the total amount of all visited pages. Using this data, we calculate the individual size for each page and take the weighted average from it.
Energy intensity of web data.
Energy is consumed in the data center, telecommunication networks, and by the end user’s computer or mobile device. This is of course different for each website and each visitor. Therefore, websitecarbon.com uses the estimated average.
The 2017 figures used are from the report On Global Electricity Usage of Communication Technology: Trends to 2030 by Anders Andrae and Tomas Edler, reduced by production energy as this is not relevant to this calculator. Then the total amount of energy consumed is divided by the total annual data transmission over the Internet described in an article in Nature magazine, How to stop data centers gobbling up the world’s electricity. This gives a figure of approximately 1.8 kilowatt hours per gigabyte.
Source of energy used by the data center.
For data center energy consumption, websitecarbon.com matches the Green Web Foundation (GWF) database to determine if the data center is using green energy. If so, the carbon emission is reduced accordingly. The estimate for the percentage of data center energy use is about 10%, which is derived by comparing the global data center energy use reported in the Nature article with the total ICT energy use (excluding manufacturing) from the Andrae and Edler report. Of course, the GWF database is not 100% perfect and includes data centers that purchase standard grid power but offset their emissions. However, for the purpose of the calculation, all are treated the same.
Carbon Intensity of Electricity.
Carbon intensity of grid electricity is based on the international average of 475 grams of CO2 equivalentยน per kilowatt hour reported by the International Energy Agency; renewable energy figures are based on wind energy data, which produces only about 7% of emissions at 33.4 grams of CO2e per kilowatt hour.
Website Traffic
When all this information is compiled, you get a pretty good idea of the emissions associated with an average user visiting a particular website.
Now multiply the carbon per page view by the number of monthly page views and you can estimate the monthly carbon emissions. If you want to learn even more about the calculation, check out https://www.websitecarbon.com/how-does-it-work/ directly.