Denver startup Cosmic Aerospace is developing a fully electric plane to reduce air pollution from regional flights.

Unlike other startups in the field, which are mostly focused on sustainable jet fuels, hydrogen, and battery tech, Cosmic has focused its engineering efforts on better propulsion systems and a unique air frame design, CEO Christopher Chahine told CNBC.

The aim is to build an electric plane that operates without any emissions but that can still fly for just over 600 miles. Existing electric aircraft can only safely carry about a dozen passengers for tens not hundreds of miles according to research by the International Council on Clean Transportation.

Chahine left a long career in energy and aviation research at the von Karman Institute for Fluid Dynamics in Brussels to make zero emissions flight a reality, enlisting Joe Wilding, the former CTO of Boom Supersonic, and Marshall Gusman, a former design leader at the supersonic jet company, to develop Cosmic’s first plane.

Cosmic aims to reduce the energy needed to carry 20 to 30 passengers up to 1,000 kilometers (more than 600 miles) by 50% or more versus traditional jet-fuel-powered planes Chahine told CNBC.

Of the many potential climate issues to tackle, Chahine focused on aviation because flights account for more than 2% of all energy-related carbon emissions today, and emissions from aviation have been growing faster than emissions from other sources of air pollution including road, rail, and shipping, according to studies by the International Energy Agency.

Besides carbon emissions, traditional aviation generates greenhouse gases including nitrogen oxides (NOx) which alter the composition of the atmosphere and can stir up ozone and methane as well. Contrails or exhaust from aviation, which include water vapor and particulate matter, also contributes to global warming, Chahine noted.

The startup has raised $1.5 million in a round of early stage funding led by Pale Blue Dot and 50 Years venture capital, two climate-focused funds.

Alex Teng, a partner at 50 Years, told CNBC his firm invested in Cosmic partly owing to the cofounders’ experience in aviation. The fund also liked that Cosmic is tackling a problem that other developers of electric planes and air taxis have not solved yet -- getting beyond the short hop flight.

“Electric aviation has always suffered from a range problem,” Teng said, “but my average flight is over 500 miles personally. When I think about a sustainable future, I know we can’t stop flying. So figuring out aerodynamic efficiency coupled with a new kind of engine is a great approach.”

Cosmic recently completed the development of a prototype engine and Teng expects the company to complete a first flight with a full-scale experimental aircraft by 2026. Cosmic is based in Denver, Colorado, with some operations in Belgium.