There is a nice piece in yesterday's Nature (here) discussing Germany's Energiewende - transformation to renewable energy. Overall the article makes it sound quite feasible; an accompanying editorial encourages the Germans to persevere in the face of moaning. This all sounds nice, but I suspect much of the optimism is based on emission reduction successes to-date. I guess there are a couple of problems with this. Obviously, to some degree we'll harvest the low-hanging fruit first - continued transformation may be more difficult or expensive. Second, and I think more importantly, it is not clear to me how Germany's accomplishments to-date depend on outsourcing emissions to China. Germany's per-capita energy use has been relatively flat (data here).


But Germany is one of the largest importers of emission according to Davis and Caldeira (2009):








Data from Peters et al. (2011) suggest that the two trends are at least related.This doesn't mean that continued and accelerated Energiewende is a bad thing or that it will be drive emissions elsewhere. However, it clearly shows that our most widely-used accounting systems are incomplete.



Davis, S. J., and K. Caldeira. 2010. Consumption-based accounting of CO2 emissions. Proceedings of the National Academy of Sciences 107:5687-5692.

Peters, G. P., J. C. Minx, C. L. Weber, and O. Edenhofer. 2011. Growth in emission transfers via international trade from 1990 to 2008. Proceedings of the National Academy of Sciences 108:8903-8908.