Rocket Lab have unveiled a new, more economical propulsion system to get rockets into space.

Auckland space technology company Rocket Lab has unveiled the world's first battery-powered rocket engine at the Space Symposium in the United States.

The 3D-printed Rutherford engine, named after New Zealand-born physicist Ernest Rutherford, will power Rocket Lab's carbon-composite rocket, the Electron.

Unveiled in 2014 but yet to be launched, the Electron is an 18-metre-long rocket designed to reduce the total time it takes to launch a satellite into orbit from years to just weeks. The rocket is expected to cost less than US$5 million (NZ$6.7m), making space more accessible.

Supplied Rocket Lab chief executive Peter Beck says the Electron rocket's propulsion system is the first new rocket propulsion cycle created in 50 years.

Rocket Lab founder and chief executive Peter Beck said the Rutherford engine is the world's first battery-powered rocket engine and the first new rocket propulsion system created in 50 years.

"It will be pretty disruptive to the industry," Beck said.

Unlike traditional propulsion cycles based on complicated and expensive gas generators, the Rutherford uses an entirely new electric propulsion cycle, using electric motors, batteries and software to drive its turbopumps.

Supplied A test cell for Rocket Lab's Electric Rutherford engine - the world's first battery powered rocket engine.

Turbopumps take propellant - in Electron's case a combination of liquid oxygen and jetfuel - out of the fuel tanks into the rocket engine to be burnt.

The electric system made the engine much more efficient and cost effective, Beck said.

The engine was produced using a 3-D printer which allowed Rocket Lab to make parts that could not be produced using alternative methods, he said.

"That enables us to produce really high-performance components for these engines."

3D printers produced very robust, high-quality parts made from titanium and alloys and reduced manufacturing time from months to days increasing affordability, he said.

The engine was unveiled at the Space Symposium in Colorado Springs, which has been running since 1984 and attracts more than 11,000 visitors.

"It's the place to be," Beck said.

The first launch of Electron was scheduled for the end of 2015 in New Zealand, Beck said.

The Electron will be capable of sending payloads of 110 kilograms into orbit.

Rocket Lab is a privately funded company. Its major investors include Khosla Ventures, Sir Stephen Tindall's K1W1 investment fund, Bessemer Venture Partners and Lockheed Martin, which designs and manufactures missiles and fighter jets for the US military.

Rocket Lab has commitments for more than 30 launches and plans to carry out at least 100 launches per year.