Take a look at this lecture by Prof. Kymakis (Barcelona, February 20-23, 2018, http://nano.teicrete.gr/ , https://nanobioconf.com/ ). It contains a lot of very interesting information. Before outdoor tests were carried out on PV-modules, they were previously extensively tested in test chambers. Greatcell should bring a mature product to market. Otherwise, we shareholders will not enjoy the long term. The world needs this technology. That's why I have so much patience.
happyman