In order to decrease your website's carbon footprint you have the possibility to make your own decisions, thus act as it best suits you to turn your website green and receive FREE certification confirming the steps you've taken. If you don't know what exactly you can do, don't worry, we can give you some hints:
Green hosting
Switch your website to a green web hosting company. Green hosting is a simple and easy way to cut your company (or personal) carbon emissions, but it will not solve all your problems.
Speed up your site
Not only search engines will be happy about it, but also the users. There are tons of ways you can speed up your website, but you can start by compressing the images and caching your content.
Simplify your website's design
Each server request takes energy on both ends. The larger the transfer, the more energy consumed. Simple designs can be both elegant and effective. You can also decrease your web site's energy usage by posting fewer images, with lower resolution, using fewer JavaScript widgets, and using less resource-intensive technology, like Flash. This will decrease load time and server requests.
Printer friendly versions of the content
Create a printer friendly version of you content by installing simple plug-ins, enabling your visitors to save ink and paper when printing from your website. This usually means that graphics are removed and content is converted to text-only. Colors are removed (to use less ink), text is converted to serif fonts, links are underlined, font size is shrunk and navigation items are removed. Some sites also remove their advertising and remove all JavaScript and other invisible coding.
Encourage the "Green Web Movement"
Your role, as someone who cares about your website and healthiness of the environment, is just as vital as those able to make the "big decisions". Place the "Green Web" badge on your website and encourage users to take steps to decrease their environment impact by setting their computer to run more efficiently.
You can choose to compensate your website's carbon footprint in any other way that can apply to your situation. Let your friends and visitors know about it!