I had found their website a little frustrating in that it never showed or even described their product. I think one reason for that is what they really have is a concept and don't want to focus on any particular product - the version of their concept that actually works may end up being very different. The lawyer in me also suspects an intellectual property reason - while they're a non-profit, they can leverage investments by selling or leasing exclusive rights, and that means they can't publish a description of their work too early.
Anyway, I wish them luck. They're operating on a shoestring budget financed by what I'm guessing are wealthy local individuals (helpful for them to be located in one of wealthiest towns in the US). They call what they're doing "eco-engineering" to distinguish it from the more blase attitude found with some geoengineering schemes.
The albedo cooling concept might also be relevant to other areas. We lose a lot of water in reservoirs to evaporation. Maybe their ideas would have application here in California, and any water saved is water we don't have to pump from hundreds of miles away - a big energy savings as well as a reduction in net demand for water.