ZeroAvia’s ZA600 hydrogen-electric powertrain can propel a 19-seat aircraft without releasing any carbon. It’s only emission: Water vapor. Inside is a fuel cell that converts green hydrogen into electricity. In 2024, the company earned approval from the U.K. Civil Aviation Authority for further experimental flights and closed a $150 million funding round, as it works toward its ultimate goal of powering the largest aircraft, including those made by Airbus, one of the company’s lead investors. ZeroAvia claims other proposed zero-emission aviation solutions, like batteries, will not ultimately be able to run jumbo jets because of the demands of aviation: a unique combination of energy requirements alongside stringent weight and space constraints. But its hydrogen-electric powertrain can. “We’re in a real burning-platform scenario,” says founder and CEO Val Miftakhov. “Everybody wants to get to 2050 at net zero. 2050 is 25 years away. Commercial aircraft last 25 years. This is one cycle. We’re already late.”