ZeroAvia, a UK- and US-based zero-emission plane maker, has added $24.3m to support the development of a 2MW hydrogen-electric engine.

Hong Kong-based venture capital firm Horizons Ventures, an existing investor and the family office for Li Ka-shing, former chairman of conglomerate CK Hutchison, led the latest funding round and was joined by new investor in flight operator British Airways.

Other investors included venture capital firms Breakthrough Energy Ventures, Ecosystem Integrity Fund, Summa Equity and Systemiq, as well as Shell Ventures, oil and gas provider shell’s corporate venturing unit.

The financing takes the company’s total equity investment to more than $53m.

Sean Doyle, British Airways’ CEO, said: “Innovative zero-emissions technology is advancing fast, and we support the development of hydrogen as an alternative fuel source because we believe it has the potential to enable us to reach true zero emissions on short-haul routes by 2050.”

In December, e-commerce firm Amazon and Shell contributed to a $21.4m series A round for ZeroAvia.

The round was co-led by Breakthrough Energy Ventures and Ecosystem Integrity Fund and included Horizons Ventures and Summa Equity, while Amazon invested through its Climate Pledge Fund and Shell participated through investment vehicle Shell Ventures.

ZeroAvia is working on a hydrogen-electric powertrain for aircraft, initially targeting small 10-to-20 seater planes. It has targeted 2023 to begin commercialising its technology, and the series A proceeds will support product development.

The company got approval for $16.3m in non-dilutive funding from the UK government’s ATI Programme.