Bill McKibben is some regularly inveighs us to “do the math” on climate change. There are however two sides to this equation: where are emissions come from and what they do. Unfortunately McKibben too often makes statements about energy that betray an unwillingness to do the math on the whole equation. A recent example came in an interview with Rumpus, where McKibben said the following about Germany.
“Here is a book to go look at. It just came out as a ninety-nine cent Kindle Single. It’s by a guy named Osha Davidson, it’s called Clean Break, and it’s about what’s going on in Germany, which is un-fucking-believable. Munich’s north of Montreal, and there were days this month when they got half their energy from solar panels. It has nothing to do with technology or location—it’s all political will, and they have it.”
Now, I have my own problems with Clean Break, but let’s focus in on what McKibben says here. Munich getting half of its energy from solar panels is quite simply impossible, for the simple reason that the majority of energy consumption is not in the form of electricity. Mixing these things up is a mistake climate communicator should not be making (Think about those “100% renewable energy by 2030 possible” headlines you read that really should say 100% renewable electricity.) The statement is even more bizarre when you realize the interview was conducted in December ,when Germany’s solar panels are not exactly going full tilt. Perhaps McKibben had May in mind, when for a couple of hours one Saturday Germany got half of its electricity from solar. Germany however is not blessed with tremendous Sun in December, having just gone through the darkest winter in 43 years. To put some numbers on this, Germany produced ten times less electricity from solar last December than in May.
Consideration of the above graph should also give to pause to McKibben or anyone else who suggests these things have nothing to do with location. Germany is in fundamental ways not very suited for solar power. Demand peaks in winter, yet solar is at rock bottom right when you need it. What you want with solar, and can get in places such as Arizona, is much flatter monthly variation in supply and not too much day to day change. Old fashioned engineering concerns however do not seem to apply in our race to a distributed energy future, where presumably an electricity grid can run on wishful thinking.