I looked for evidence for your claim as in my mind, energy consumption for the ad industry would not be that impressive. I found a paper written in 2010 for th

I looked for evidence for your claim as in my mind, energy consumption for the ad industry would not be that impressive. I found a paper written in 2010 for the Netherlands [1], claiming that : "Thus, web advertisements increase the total energy consumption of PCs by 3.4%." That's not counting the cost of running the infrastructure, and I suspect ads and tracking probably did not evolve in the right (i.e. less energy hungry) way in the last 9 years. As for the current consumption of power by 'client devices', it is estimated to consume 5% of total world electricity [2] I could not find any number on the energy consumption on the other side, i.e. servers/infras. As a (very) rough estimation, without taking into account the 'server' side of ads, we can estimate the energy cost of ads to represent ~0.17% of total energy produced in a year. In the end, I stand corrected : the amount of energy consumed is far from negligible at that scale. However, while it is definitely not negligible on absolute terms, I think there are lower hanging fruits to focus on to fight global warming, such as reliance on fossil fuels, common use of products made on the other side of the world, meat consumption... [1] : https://research.utwente.nl/en/publications/the-hidden-energy-cost-of-web-advertising https://research.utwente.nl/en/publications/the-hidden-energ... [2] : http://www.climatechangenews.com/2017/12/11/tsunami-data-consume-one-fifth-global-electricity-2025/ http://www.climatechangenews.com/2017/12/11/tsunami-data-con...