Indirect carbon emissions from four of the world’s leading tech companies surged by an average of 150% between 2020 and 2023, driven by the operational demands of data centers powering artificial intelligence (AI) systems, according to a recent report by a United Nations (UN) body. The International Telecommunication Union (ITU) stated that the use of AI by tech giants Amazon, Microsoft, Alphabet, and Meta has significantly increased indirect emissions due to the high energy consumption of data centers. Indirect emissions refer to greenhouse gases generated from electricity, steam, heating, and cooling consumed by companies.

Among them, Amazon experienced the most significant rise in emissions, with a 182% increase in 2023 compared to three years earlier. Microsoft followed with a 155% rise, Meta with 145%, and Alphabet with a 138% increase. The ITU report tracked greenhouse gas emissions from 200 leading tech companies over the 2020–2023 period.

In response to the report, Meta — which operates Facebook, Instagram, and WhatsApp — directed Reuters to its corporate sustainability report. Meta's management stated that the company is currently working to reduce its carbon emissions, energy usage, and water consumption across its data center operations.

Amazon, meanwhile, affirmed its commitment to more sustainable practices through investments in carbon-free projects, including renewable and nuclear energy. Microsoft, referencing its sustainability report, reported that it doubled its energy efficiency in the past year. The company is now transitioning to liquid-based cooling systems at the chip level to replace traditional cooling technologies in an effort to reduce data center power consumption.

Other companies mentioned in the report have not yet responded to requests for comment. As AI investments continue to grow, the ITU estimates that the highest-emitting AI systems could generate up to 102.6 million tons of CO2 annually. The energy requirements of data centers involved in AI development are also expected to place further strain on existing energy infrastructures.

“The rapid expansion of artificial intelligence is driving a sharp increase in global electricity demand, with data center power consumption rising four times faster than overall electricity use,” the report noted. It also pointed out that while more digital companies are setting emission reduction goals, these ambitions have not yet translated into concrete decreases in emissions.