Adrian Harvey writes:
The New Zealand based commercial space company Rocket Lab has unveiled their new rocket engine which the media is describing as battery-powered. It still uses fuel, of course, but has an entirely new propulsion cycle which uses electric motors to drive its turbopumps.
To add to the interest over the design, it uses 3D printing for all its primary components. First launch is expected this year, with commercial operations commencing in 2016.
For one-off or small production lots that are common in space applications, metal 3D printing (DMLS) can be considerably cheaper and faster. It eliminates the need for expensive casting tools and hand fabrication that is expensive and difficult to reproduce.
Although, I don't know how it comes out to be more efficient to carry fixed mass, relatively low energy density batteries on a rocket. I would have figured the added weight of the batteries and electric motor would be significantly greater than a small combustor and turbine + the fuel to drive it. In space applications you're usually trying to do everything you can to minimize the dry weight of the platform.