Oil Drum Debate with Nick on Intermittency

I tend at times to get involved in online dabates. At the very least dentes are methods of self education. I do listen to what the other side says, and sometimes I change my mind, if confronted with a question to which I have no good answer. I have, for example, modified prior views on the genetic basis of behavior, although the issues are far more complex than the genetic determinist would allow for.

My oil drum debate with Nick, was triggered by claims of another commenter, Chris. Chris claimed that renewable power sources were inherently more efficient than nuclear. Part of my responce was to point to the problem of intermittency with renewables.

Nick responded to that comment with a statement that began:
"Intermittency is greatly exaggerated as a problem for renewables. That said, I have to say I find this argument silly, and intellectually dishonest on both sides."

"Nuclear advocates point to non-problems (like intermittency) . . ."

I responded to Nick:

In my book claiming that intermittency is a non-problem is where the intellectual dishonesty lies. Intermittency is a non-problem, only for supplemental power. Intermediacy becomes a problem once renewables are offered as base or even peak power. There are three methods of coping with the problem of intermittency, back up generation with fossil fuels, energy storage, or massive renewable generation redundancies. Each method requires the building and maintenance of duplicate facilities, in order to cope with the intermittency.y.

Nick responded back by apologizing for saying that my point about intermediacy is intellectually dishonest, He then stated that:

There are more, and better, methods of coping than that. First is connecting grids at the edges in order to reduce the variance (aka intermittency) of various generation sources. If you make your grid effectively large enough, variance becomes manageable. This is relatively low cost, as you don't need the kind of earth-girdling cables envisioned by another TOD post recently, you just need to connect grids at the edge.

2nd is demand management: if you make meters dynamic and time-of-day sensitive, and have a large % of demand which is flexible and schedulable, generating variance becomes much easier to deal with. For instance, if you have 100M EV's (as we will in the US, in one form or another), you have a very large demand which can be shifted at essentially no cost.

3rd is location and source tuning: using both the predictable patterns of certain negatively correlated wind locations, and the negative correlation of wind and solar to reduce system variance. This costs nothing but the time spent in planning and regulating installations, something system operators should be doing now. - Nick

I responded to Nick:

Nick, I am pleased that you are willing to dialogue about this. Let me address you your preferred methods of coping with intermediacy. I will take them out of order. You suggest demand management as a coping method. Demand variation is something of a problem for nuclear power, so I have looked at the issue from that viewpoint. There are flexible demands, that is demands that can be shifted to other times, and methods of altering consumer behavior, however some demands will remain inflexible, For example the demand for power for air conditioning in the summer. Texas is as you are probably aware quite hot in the summer, and the heat is actually a health hazard. There is no why you can get people at home to turn off their air conditioners on hot summer nights in Texas.

You suggest connection to the grid as a means of providing electricity, but how is the power going to be generated. The sun is down so solar sources are out of the picture. Texas summer wind potential drops too. I believe that the capacity factor for Texas wind generators is below 17%. But worse, the wind is highly variable, and wind output may drop to zero all over the state. Thus wind generation would provide Texas with the worst of all possible worlds, high generator redundancy plus unreliability. If your wind system is built to compensate for a capacity factor of 17%, you will build so many windmills that it would be far cheaper to just build all nuks. Thus the grid seems to provide no solution to the problems of renewables.

Finally you suggest location and source tuning. I assume that in my thought experiments on renewables. I assume that wind generators will be located in the best locations, and that solar generation will be located in the Southwest. But putting solar in the Southwest will not stop the sun from going down. And building windmills in the Texas Panhandle is not going to give you the power you need to keep Texas Air Conditioners running all night long on Texas Summer nights.

My argument for charging the energy input of backup fossil fuel plants to renewables is this. A renewable power system, as I believe I have just successfully demonstrated, is not capable of always meeting electrical demand. Ergo, it requires alternative sources of electricity, lets call them the green crutch, as backups. Now if you went with an all nuclear system, the crutch would not be needed. We can throw the crutch away, by recognizing the limits of renewables, and not expecting more than they can deliver.

The limits are these. Wind will never be reliable enough to serve as base or peak power. Therefore wind of of very limited utility outside reducing CO2 emissions. Wind can only serve as a supplement to fossil fuel power, If fossil fuel power needs to go away, there is no rational for wind.

Solar is good at providing daytime power. But solar power imposed penalties and expenses related to materials demand, land use and security. At present the capitol costs of solar exceed that of nuclear, and the cost of materials for building solar facilities are rising. Therefore solar is a candidate for daytime peak power, but may never fulfill its expectations. Furthermore, if solar power is marginal in the Southwest, its performance will be far worse in other parts of the country.

My conclusion then is that at present, only nuclear power can fully substitute for fossil fuel power sources. Furthermore, without some significant breakthroughs in the generation and storage of solar power, the substitution of nuclear for fossil fuels is inevitable.

Afterward: I by no means think that Nick's remedies are bad in themselves, it is just that they don't do for renewables, what renewables advocates say they will. Interconnecting the grid is already working for much of the United States. For example the Southeast exports power to the North in the winter, while importing power from the North during the summer. That helps both areas get by without adding seasonal capacity to meet peak demand. Such a swap is not so easy for Texas. Much of our peak generating capacity is from natural gas. Texas consumers are burning gas in the winter to keep warm. The gas producers would rather sell gas to consumers in the winter, than to sell it to electric companies. The fact that the gas producers have a surplus of natural gas in the summer means that gas is on the market for power production during the summer in Texas. Adding an interstate grid connection to the Texas power system does not help Texas meet peak summer demand. Summer is a peak demand time for the most likely exporters of power to Texas, while power generation by wind drops all over the country.

Update: “What we know, is the wind blows sufficient for these windmills to be producing about 35%, perhaps 40% of the time. So the paradox of building windmills is that you have to build a lot of ordinary power stations to back them up and those are going to be almost certainly gas in the short to medium term and that’s what’s required. If you ask the question who’s making sure that there’s enough gas stations out there to back up the windmills the answer is nobody.” - Dr Dieter Helm, Energy Economist and Fellow in Economics, New College, Oxford