TCASE 4/ Energy system build rates and material inputs

TCASE 4 is the fourth in Barry Brook’s extended series ‘Thinking critically about sustainable energy‘. The series goal is to provide a comprehensive analysis of the zero-carbon global energy future. In particular, what are the real-world costs, risks and benefits of all the strategies for achieving a zero-carbon generation capability that can satisfy real-world demand.
In TCASE 3 Barry concluded that to satisfy 2050 demand we need to commission the equivalent of two AP1000 size nuclear reactor every three days through 2050. In TCASE 4 Barry examines the scalability of the competing technologies. Click the thumbnail for the full size summary graphic. Here’s Barry’s concluding paragraph – I can’t think of a more succinct summary:

The main point of this post, TCASE 4, is to take a one step in quashing the absurd ‘bait-and-switch’ meme that some disingenuous anti-nuclear folk repeat: That because the energy replacement challenge facing nuclear energy is huge (a 25-fold expansion on today’s levels), it couldn’t possibly do it, so renewables are our only sensible option. On the basis of this post alone, any objective reader can see that this is pure, quantitatively unsupportable, nonsense. It’s going to be really tough, no matter what — and believe me, I’ve not even warmed up on the problems with renewables taking the lion’s share of the work.

TCASE 4 is a 10,000 meter surveillance flight over the topic. The entire series is intended to be comprised of bite-sized pieces, so don’t expect every detail to be covered here. That said there are very useful illuminations in the comments,such as this reply by  Barry Brook to a question “won’t the wind capacity factors be higher?”

Barry Brook said

19 October 2009 at 16.54

Neil #10: The global and US numbers don’t bear this out. Go and look here:

Table: Annual Wind Power Generation (TWh) and total electricity consumption(TWh) for 10 largest countries.

The US has amongst the highest CF of all countries. Further, the change in CF for wind, across years in the US or other nations, is pretty stable. It seems that although a CF of 35-45% is often cited for wind for the best sites, when taken across whole nations, the actual figure turns out to be considerably lower.

In reality, this is quite a complex matter and will deserve a couple of posts on just this point in the TCASE series. For instance, CF can be ‘tuned’ to a site — it ultimately depends on what sized generator you install on your turbine. If you put a GE 2.5xl-sized turbine at a good site and whacked a 200 kW generator on instead of a 2.5 MW generator, you’d likely get the CF up to 70-80% — but this would obviously not be helpful, as it would be grossly uneconomic!

On balance, I strongly suspect that a worldwide CF of ~25% for 10 TWe would turn out to be a very reasonable figure, as the trade-off between use marginal improvements in turbine efficiency is offset by the increasing use of less-than-optimal sites.

Next I noted this exchange which touches on one of the unspoken cost burdens of nuclear generation — the vast overkill in regulations that supposedly improve safety:

Douglas Wise said

20 October 2009 at 1.31

Re # 11. Peter Lang

Peter, I wonder if you could take the time to categorise those safety requirements for nuclear power stations which you consider to be “over the top” relative to the safety requirements imposed on other industrial complexes (eg chemical plants) which you deem to be potentially as or more dangerous. I am not attempting to take issue with you, merely to try to get a handle on the extent to which redundant safety engineering impacts on build costs (both with respect to build time and physical resources). How, for example, would you rate containment in reactors that operate either at high or low atmospheric pressures? Should one need to protect against accidental or deliberate aircraft strikes? As I understasnd it, chemical plants are generally not so protected.

Tom Blees said

20 October 2009 at 4.25

Doug @ 16: The PRISM reactor vessel (the commercial IFR design) is designed to be underground, about 50 feet below grade. If they’re built with the attendant structures (steam generator and turbine) off to the side rather than directly above, then one can use the 50 feet of earth as protection against aircraft strikes. The engineering for this is straightforward. One need only transfer hot (~550C) sodium from the reactor vessel (at near atmospheric pressure) to the steam generator via the secondary (non-radioactive) sodium loop. Want more protection? Pile on more dirt. It’s dirt cheap.