Bill Gates continues his study of energy policy: Bill has repeatedly demonstrated that he knows how to winnow out credible experts in each field that he is studying. Ken Caldeira is certainly an excellent choice to critique the “electricity from kites” idea.
Energy sources that provide power without producing CO2 are critical to addressing the challenge of global warming. The book Sustainable Energy – without the hot air prompted Bill to ask climate researcher Ken Caldeira what the prospects are for generating power from wind in the upper atmosphere.
I just finished David MacKay’s Sustainable Energy – without the hot air.
He talks about every renewable form of energy I know of except for high wind.
He does a really good job of looking at the potential size of contributions from different things like geothermal and others.
I wonder if he didn’t include high wind because it is viewed as so difficult and unlikely to work or if the contribution potential is so small.
I remember you mentioned some start-ups in the high wind area.
I wonder if there has been any progress in their work.
I guess it is the physics of getting the kites to stay up even in storms and low wind combined with the problem of bringing the power down that is hard.
Ken Caldeira
I have spoken with several people in several companies and they all seem to think different things are the main impediment.
My understanding is that one of the big impediments is tether mass, and there are big tradeoffs with mass of the conductor and insulation versus how high up you can go. It might be that we would require something nearly magical to make such systems really work economically.
(Everything else you mention is also a concern.)
I would say that this is one area in which the size of the investment compared to the size of potential return is tiny, especially when compared with investments such as fusion power.
We recently did a study on steadiness and availability of high altitude winds. The conclusion is that there is a huge amount of power available but that it still is too unsteady to provide base load power without continental (or global?) scale distribution systems, back-up power, or unbelievable amounts of storage.
The other thing we should recall is that if we were to meet future power demand by this source exclusively, we must intercept more than 1% of natural flows. I think when we get above a 1% change in a natural system, we need to be concerned about large scale unintended consequences. Remember, global warming is basically a 1% problem – 1% warming of our 288 K planetary temperature. (That is one reason why solar is so attractive – with solar we are talking about capturing 0.01 % of the energy that hits the ground.)
Readers know that I am generally a technology optimist. But I just don’t see how the kite-energy idea could ever scale to compete with mass-manufactured nuclear power modules. If it isn’t cheaper than coal it is a diversion.
Nuclear with advanced fuel cycles is one of the most promising approaches to scalable and affordable carbon-neutral power.
I do think a balanced R&D portfolio would put some money into high altitude wind power even if it ends up not being overwhelming attractive. In general, I would put some resources in exploring every technological approach that is not hampered by fundamental thermodynamic or mass-balance constraints.
The current public R&D investment in high altitude wind power is zero. That is not the right number. If you want to argue that the level of investment should be two orders of magnitude less than what goes into advanced nuclear reactor designs and fuel cycles, I might agree with you.
I think we can be sophisticated enough to have a balanced R&D portfolio without thinking that everything that everything that is not our biggest bet is just a diversion.
Ken: (…) I think we can be sophisticated enough to have a balanced R&D portfolio without thinking that everything that is not our biggest bet is just a diversion.
Thank you for your comments. I accept your correction on the general principal, and defer to your superior knowledge of the potential of high wind.
I certainly understand the rationale behind “let a thousand flowers bloom” [I think Mao actually said a "hundred..."]. What troubles me is when the policy becomes “make a thousand flowers bloom” by converting taxpayer income into government R&D grants or subsidies. That is inherently a political process that misallocates capital.
But a purely free market approach to funding R&D also misallocates capital, especially where the payoffs are likely to yield much larger public welfare benefits than the economic returns to the innovator. E.g., NIH R&D grants. So I take your point that we can justify more taxpayer supported energy R&D, probably a large multiple.
If Dr. Caldeira was “czar” of this additional funding how would he solve the allocation challenge?
I’ve had only one idea on allocation that I think is applicable to our specific goal of replacing fossil fuels. The “cheaper than coal” objective is really different from NIH, in that we are seeking technologies that are both scalable and commercially competitive, and deployable at scale within three decades. We do not need technologies that can only compete by virtue of continuing large taxpayer subsidies.
I think our definition of the energy policy goal is compatible with the free-market incentives. If so, can we leverage up those incentives enough to attract private capital? As a thought experiment, suppose the DOE R&D grants are proportional to private capital. Say we authorize DOE to grant up to four times the amount of the matching private project/venture capital on offer. The ability of a project to attract private capital is a not-foolproof but still very powerful way to vet the economic viability of the outcome, and the scalability. The risk-reward profile can be tuned by what rights accrue to the taxpayers in return for the grant (which rights could vary from the classic government “gift” to long-term debt to equity).
An obvious weakness of my proposal is that it doesn’t really create a moat to keep the politicians out of the allocation process. I do believe it would redirect some proportion of the funding that would normally be awarded to politically-favored projects.
Nuclear with advanced fuel cycles is one of the most promising approaches to scalable and affordable carbon-neutral power.
Indeed. I am optimistic that political leadership plus some analog of the taxpayer + private venture funding will allow the start of deployment of advanced reactors, at scale, somewhere in the three decade future. Given a ramping carbon tax it might happen in three decades with no taxpayer participation. But I think it is too risky to rely only on even the best William Nordhaus carbon tax schedule. Even though the Chinese are accelerating new nuclear deployment, current technology is too slow to prevent large scale new Chinese coal plants. So we need to work with China and India so that they will have a deployable nuclear- instead-of-coal option as quickly as we can get there.
I will argue that it is vitally important that we do not wait for fully commercial Gen IV to arrive. The now-deliverable options such as AP1000 and EPR are safe and probably economic today. With political leadership, including streamlining the regulatory process, in about a decade we might be able to stop developed country deployment of new coal plants, even without a carbon price.
Given a fee-and-dividend carbon tax, then (I think) we can definitely switch those new plants away from coal. And accomplish that change without wrecking the US or Chinese economies. If we succeed to get to volume production of Gen IV modules in three decades, then I speculate we will be able to replace the remaining coal boilers by about 2050.
Those are very ambitious schedules, which is what provokes me to worry about “diversion” of focus away from the one path that I am confident will work. So I would argue that first we put all focus on getting the nuclear solution on track. Once underway, then we broaden the taxpayer support to ”let a hundred flowers bloom”.