Rotary engines are great they give out alot of power to the wheels and plenty of return power the source.
You can make the engine run on small anouts of fuel, ans were hoping to do this if hydrogen has a larger power output compared to conventional fuels, 3 to 1 i read somewhere, might have to check ton that..
Re:The engine we decided on was a rotary 8 Months ago
Yes that is the plan, much less hydrogen or fuel source, water will be used. If you are not sure what a rotary engine looks like or even is, here is a good 3D video.