After doing a bit of research it seems as if it is going to be in larger production some time next year:

+ Is GravityLight available to buy?

The new GravityLight model, GL02, is exclusively available through our Indiegogo campaign. Your support will also be helping us establish an assembly line in Kenya and start production in Spring 2016! NB. our first GravityLight design, GL01, was produced as a one-off batch of 7000, used in our global field trial and for the supporters of our first crowdfunding campaign.

It sounds like they are really onto something.  Would you buy one of these or are you going to wait?

It is this type of outside the box thinking that will lead to real scientific advancements!

Thanks to gravity light for the great info