An optimistic take on fighting climate change

This is a relatively optimistic, though I think well-founded, take on the prospect of the human race's limiting the horrific consequences of global warming through technological innovation and political commitments.  It jars me from my default setting of resigned despair regarding the future of the world.  The one major threat it identifies is the prospect of a Republican US president in 2016 derailing all of our country's regulatory framework around carbon emissions.  Here too is an article describing the economic and industrial details of how renewable energy generation has gotten so cheap, so fast.