Listened to this interview with the CEO and founder of Ecosia. Unfortunately the interview is not available in English, but here is a transcript of the description. I’m definitely switching to Ecosia as my main search engine where possible now.
Fun fact: Ecosia is the biggest European search engine. The search results are provided by Bing, which is a Microsoft product. The company has plans to be carbon negative by the end of the decade:
By 2030 Microsoft will be carbon negative, and by 2050 Microsoft will remove from the environment all the carbon the company has emitted either directly or by electrical consumption since it was founded in 1975.