This is a worthwhile subject, but I was very disappointed in the way the information was presented. Comparing our gigawatts of photvoltaic capacity and total renewable energy capacity directly to that of other countries, instead as a percentage of our total or as a per capita amount, is very misleading. For example, Germany has about 82 million people and Spain about 45 milion, compared to 310 million people in the U.S. The graphs presented make it look like Germany is doing 3.5 times as well as the US in photvoltaic capcity, when by any reasonable comparison (% or per capita) they are actually doing 12 times as well! Spain appears to be doing something over twice as well, when infact they are doing more like 14 times as well! Your publication is generally very well done scientifically, but this isn't. The problem is compounded in that some of the graphics are presented appropriately, using percentages, and people might assume the graphics are all equally reliable.