But suppose I had a Kickstarter for a car on the same premises: "A revolutionary car powered by sunlight and water - fill up with water every now and then, and it will run forever". No further details. Would you buy?
I think it's a very small percentage of the world that would know off the bat why "sun and water" could work for a spacecraft, but not for a car.
I think some more detail on the physics behind it, aimed slightly below say Physics 101 level, would help to convince more people to contribute. It makes it simpler to distinguish this from "crystals can change your life" or "lose X pounds of weight in Y days" style marketing, which promise the moon but don't explain how their miracle is supposed to work.
They do give an explanation in their link[0], but I think having a summarized version on the Kickstarter page itself would help donations. (To be clear, this is a comment on the marketing, not on the physics or feasability.)