Joe, I see why you have reached the conclusion you have, and I confess that my immediate reaction was the same…that this argument is a distraction, and poorly timed, especially in an era when those that want to preserve the status quo (or worse, turn back the clock on progress) will do all they can to divide and conquer. And I’ve said as much to Chris. But this is an important discussion to have, provided that it is caveated at all points by the fact that Clack and Jacobson actually AGREE that high penetration renewables at 80%+ are the only viable way to combat climate change. The reason the debate is important is that beyond 80%, the cost of incrementally increasing renewable energy penetration becomes exponentially higher and the last thing we need is examples at smaller scales (e.g. HI, CA) providing fodder for policymakers elsewhere to throw up their hands and say the transition is too expensive to do reliably. Since policymakers listen to Jacobson, the fact that it is quite clear that many of his assumptions are questionable, and when properly considered will vastly increase costs, MATTERS.
Can we do 100% renewables? Yes, of course it is technologically possible if you throw enough money at it. But if you want to be pragmatic and have any hope of making the transition at the speed we need to be moving, at a cost that is acceptable, then advocating for 100% renewables is a recipe for a train wreck, and the populist backlash that comes with it could finish off any hope we have of making progress before the severe impacts of climate change force more reactive adaptation. Even though society at large is beginning to understand that climate change is real and serious, most people have very little comprehension of just how serious it is. Thus, we MUST take the most sensible route to mitigation that is lowest cost, lowest risk and most likely to succeed. That is the motivation of Chris and colleagues and is why airing this dirty laundry in public is a necessary evil. They want to make sure that policymakers understand that what Jacobson is proposing may be technically possible, but is not based on a realistic approach to transition of the existing electric system. As it is, the path to high penetration is extraordinarily politically challenging (unless one lives in a bubble in which the extreme left can achieve whatever goals they propose; we’ve seen where that has got us, right?). That’s aside from requiring a wholesale rethinking of how the power grid functions; a rethink that will ultimately be incredibly beneficial regardless of the generation type but will nonetheless be met by resistance at every turn.
What I do agree with you about is that name calling and uncivil discourse is totally counterproductive. In particular, Jacobson calling Clack et al fossil fuel and nuclear shills is absolutely inexcusable. I consider myself about as informed and alarmed as any atmospheric scientist/renewable energy expert can be about climate change, and can assure you that Chris is as passionate about getting us off carbon based energy as anyone. To suggest that experts noting that an 80–90% RE target is likely to have better outcomes than a 100% renewables target are anti-renewables as a result is simply ridiculous. Such discourse is bad enough from our embarrassment of an executive branch. I sure hope it isn’t going to continue to infect intelligent discussion between experts who one hopes can influence appropriate decision making on climate change mitigation; it totally undermines credibility.
The critique needed to be public for transparency and to get the attention of decision makers. Rebuttals need to be evidence based not emotional. The protagonists on both side need to calm down, acknowledge their common ground (a desire to decarbonize the economy) and allow each other to save face, but this discussion MUST be had.