One Of The World's Busiest Airports Has Gone 100% Carbon-Free

It takes a massive amount of energy to power an airport. Service terminal buildings, ground vehicles, and support equipment are just a few factors to consider in an airport's energy expenditure. As such, it's hard to imagine a huge international airport switching to primarily renewable energy and generating zero carbon emissions. But surprisingly, one of the busiest airports in the United States has achieved this impressive task.

Chicago O'Hare International Airport transitioned to 100% renewable energy on January 1, 2025. However, this feat is not Chicago's only environmental accomplishment. This milestone was part of a larger mission to reduce the citywide carbon footprint and today, 400 of the city's municipal buildings run on renewable energy. This includes fire stations, water treatment plants, and the city's smaller Midway Airport. So, how did Chicago achieve such an impressive goal? Primarily through renewable energy sources including one of the newest and largest solar farms in the U.S. The remaining 30% comes from purchased energy credits.

Chicago O'Hare is the ninth busiest airport worldwide, serving over 70 million passengers annually. Given its high traffic and energy consumption, going carbon-free is a huge accomplishment — not just for the airport but for the future of air travel. It's a sign to the rest of the world's airports that they can — and should — follow suit.

When fossil fuels are burned for energy, carbon dioxide is released. This is one of several greenhouse gases that trap heat in the atmosphere and drive climate change, resulting in rising global temperatures and extreme weather events. Unfortunately, aviation is a major contributor and one of the fastest-growing sources of carbon emissions globally. According to Our World in Data, aviation accounts for approximately 2.5% of global carbon dioxide emissions and this number is only increasing as air travel becomes more popular and accessible.

Initiatives have sprung up to decrease this negative environmental impact, including the Global Net Zero Coalition, an international commitment to reduce carbon emissions to zero by 2050. Several airports have jumped on board and according to ACI Europe, airports in Scandinavia, Portugal, Italy, and the Netherlands have already achieved a net zero goal. Other European airports are on target to achieve carbon neutrality by 2050.

Meanwhile, Dallas Fort Worth Airport prides itself on being the first carbon-neutral airport in the Americas. However, more and more airports are joining the cause. San Diego and Vancouver International Airports earned the coveted carbon-neutral status shortly after, and now Chicago O'Hare can count itself among these sustainability leaders. This is great news seeing how more airports jumping aboard could mean less greenhouse gas emissions, resulting in a healthier and safer environment for all.