|source: http://is.gd/ZdXqFS via twitter http://twitter.com/#!/LPPX|
Amateur alert: figures may be not be exact. Fiddling around with this, it looks like an array of 5 of these could propel 30000 kg dry mass out of Earth orbit in less than 300 days. Not fast enough for a manned mission, but perhaps useful to deliver cargo back and forth between the Earth and Moon. Modest amount of propellant would be needed. Assuming the thing had a long service life, it may be feasible as a space truck to deliver commercial cargo to and from the Moon.