It also doesn’t make a great deal of sense to combine intermittent renewables with nuclear
Although you’re right, it appears the renewables juggernaut is unstoppable, and mass production for affordable reactors will require at least 15 years to spin up, during which time renewables will be the only game in town. For that reason, MSR vendors want to use huge silos of solar salt to store energy when renewables are going strong, which they can discharge when the renewables start losing power. In this way the nuclear reactor can be kept on most of the time, albeit at the cost of extra turbines and solar salt (so named because it was pioneered by concentrated solar power technology).
Educating away people’s political convictions has seen very limited success when it comes to convincing them that radical action on climate is needed.
I would point out that this has been largely liberals trying to convince conservatives about climate science; cross-tribe communication is pretty difficult. Indeed, I wonder if support for nuclear among conservatives stems as much from opposing the “liberal media”’s scare mongering than anything else. There’s been some success, at least on the left, from efforts to get the word out about “the” 97% consensus among climate scientists. Educating people on the left seems like an easier problem—there are die-hard anti-nukes who can’t be convinced, but they’re a small minority.
AFAIK no one has seriously attempted the educational resource I propose, so before saying it can’t work I think it’s worth trying. We do have some stuff like Gordon McDowell’s videos that basically targets maven personalities like myself, but I found that it still doesn’t provide all the information I need to get a complete mental model for nuclear power. An educational site is not enough by itself to change public opinion, but it could at least be valuable to maven-type people who want to change minds about nuclear power but don’t have good sources of information that they can link to and learn from.
Public opinion is a very hard nut to crack, but what about the media? I would guess that influencers like Jon Oliver probably got some of their information from SkepticalScience, so I think public education may be able to percolate to the people by first percolating up to the media.
Nuclear energy is unpopular.
I am very much aware. That’s what I think we should take steps to address. Providing educational resources isn’t enough by itself, but it’s a necessary step.
I’d like to make a few points based on my knowledge as someone who studies climate science issues as a hobby. I’m a member of the volunteer team at SkepticalScience (an anti-climate-misinformation site).
[edits/additions in square brackets; original version contained mistakes]
First, humanity needs to reduce carbon emissions all the way to zero or below, because natural removal of CO2 from the climate system is extraordinarily slow. 50% is too much; 25% is too much. Zero. Popularly-considered strategies for mitigating global warming won’t achieve that. Optimistic IPCC scenarios like like RCP 2.6 assume technology will also be widely deployed to remove CO2 from the air. Things like tree planting that increase biomass can slow down the increase of CO2 but can’t stop it even briefly; other ideas for carbon sequestration are not economical [AFAIK] and it’s irresponsible to simply assume an economical technology for this will be invented. Therefore, we need to switch to 100% clean energy, and do so as soon as possible.
In my opinion the best thing the EA community can do (under the importance-tractability-neglectedness framework) is to study and support nuclear energy in some affordable way. In the past, the push for climate change mitigation has come from traditional environmentalists, who have fought against nuclear power since at least the early 1980s and mostly haven’t reconsidered. This is evident from the many campaigns for “renewable energy” rather than “clean” or even “sustainable” energy. EA can fill a gap here. My favorite thing is to ask people to support new, inexpensive Molten Salt Reactor (MSR) designs. But probably the cheapest thing we can do is a web site. I think there is a real need for a web site about nuclear facts (or clean energy facts generally), something that debunks myths like SkepticalScience does for climate science, and also provides information that isn’t adequately available on the web right now, about such topics as the risks of radiation, the types and quantities of nuclear waste, and the ways nuclear regulations have improved safety (albeit increasing costs). And, of course, it would go into some detail about MSRs and other affordable next-generation reactor designs. As EAs are not funded by the nuclear industry, they could be a credible independent voice.
Solar power makes great sense in a lot of tropical places, but in northern climates like Canada it doesn’t, as peak energy use happens in the wintertime when the sun is very weak. AFAICT this makes solar in Canada into a nuisance, a potential roadblock as we get close to 100% clean energy (why would we deploy more clean energy if existing solar power makes it redundant for half of each year?). Without nuclear power, our main source of energy [in such climates] would probably have to be wind, and I’m very concerned that the cost of relying mostly on wind power would be prohibitive, especially in a free-market system. I don’t know the exact numbers, but once we exceed something like 25%-30% average wind power, instantaneous wind power will often exceed 100% of demand, after which wind turbines are likely to become less and less economical. (Epistemic status: educated guess—do we have any experts here on the economics of switching to an extremely high penetration of nondispatchable energy?)
[Meanwhile, right now nuclear advocates often rely on bare assertions, some of which are wrong. Without credible-but-readable sources—plain language explanations that cite textbooks, scientific literature and government reports—it’s hard to convince intellectuals and reasonable skeptics to change their mind. Anti-nukes can simply assert that claims that make nuclear power look not-scary are nuclear-industry propaganda. Note that nuclear power relies on public opinion much more than renewables currently do—company are free to design and build new wind turbines, but nuclear power is, of necessity, highly regulated and its continued existence relies on political will, which in turn flows from popular opinion. Witness the blanket shutdown of all nuclear power in Germany. Hence the motivation for an educational site.]
By contrast, it seems clear to me that mass-produced MSRs can [theoretically] be cheaper than today’s CCGTs (natural gas plants). I’ve been following MSRs with great interest and I’ve published an article about it on medium, although it remains unlisted because I’m still uncertain about a couple of points in the article and I’d love to get a nuclear expert to review it.Second, it is a common misconception that we could have 4°C of global warming by 2100; climate scientists generally don’t think so [except in the RCP 8.5 (business as usual) scenario which by now is more of a “look at the train wreck we’re avoiding!” than a plausible outcome]. Often this misconception arises because there are two measurements of the warming effect of CO2, and the most commonly reported measure is ECS (equilibrium climate sensitivity) which predicts the amount of warming caused by doubling CO2 levels and then waiting for the climate system to adjust. The best estimate of ECS is 3°C (2.0-4.5°C, 90% confidence interval according to the IPCC) and it will take at least 200 years after CO2 doubles to even approach that amount of warming. If the ECS is higher than 3°C I would expect it to take even longer to approach equilibrium, but I’m rather uncertain about that.
To estimate the warming we expect by 2100, look at the TCR (Transient Climate Response) instead. The TCR is highly likely to be in the range 1.0-2.5°C. Keep in mind, however, that only 2⁄3 of greenhouse warming comes from CO2 according to the AGGI; 1⁄6 comes from methane and the final 1⁄6 from all other human-added greenhouse gases combined. The most common estimate of TCR is 1.7°C or 1.8°C and a first-order estimate based on observed warming so far is about 1.5°C. So if CO2 doubles (to 560 ppm), I’d expect about 2.5±1.1°C of global warming based on a TCR of 1.75, assuming CO2′s fraction of all GHGs increases slightly by then. [side note: I would be surprised if CO2 more than doubles—I think we’ll get almost 100% clean energy by 2100; OTOH predicting the future isn’t really my forte.]
Third, Having said that, the land will warm a lot faster than the oceans. Climate models on average predict 55% more warming on land than sea [related paper]. [Observations so far suggest that the transient] difference is even greater. Therefore, although 4°C of “global” warming by 2100 is highly unlikely, 4°C of land warming by 2100 is a distinct possibility (though I estimate a probability below 50%.)
I guessed on Metaculus that global warming by 2100 would be [1.7 to 2.6°C] (despite the Paris agreement), but on land [it’s likely to reach 3°C (and as climate change is non-uniform, some populated locations could exceed 3°C even if the land average is less than 3.)]
Fourth, having lived in the northern Philippines, I think the impact of the warming itself is underappreciated. I lived in a very humid town (more humid and hotter than Hawaii) where the temperature exceeded 30°C in the shade most days. The hottest day of the year was about 37°C in the shade at noon, coldest would have been around 18°C at 6AM.
Maybe it’s just that I lived in Canada too long, but humans are humans—we are naturally uncomfortable if our core temperature exceeds 37°C and I became uncomfortable whenever I went outside or left the sanctuary of the Air Conditioner. So for the sake of Filipinos and the other 3+ billion people living in tropical latitudes, I think we should be very concerned about the effect of just the warming itself on humanity’s quality of life.
If we get 4°C of warming vs preindustrial, that implies average daily highs of about 33-34°C in my town, which I would describe as virtually unbearable at 75% humidity. Consider also that if the Philippines becomes more prosperous, they will respond to the high temperatures by extensive use of air conditioning, which is energy intensive. If we don’t stop using fossil fuels soon, air conditioning itself can become a significant contributor to further global warming.
2. My assumptions were that geoengineering might reduce society’s drive for mitigation (the switch to clean energy), and that it would be used to halt the temperature increase.
In the linked paper (Keith & Macmartin 2015) their proposal [actually they use the word “scenario”—I don’t think they are going so far as to endorse it as a plan] is a bit different. They propose to use *half* as much aerosols as would be required to halt global warming (this is a bit tricky to get right, e.g. the radiative forcing of aerosols has much greater uncertainty than the forcing of CO2, so their proposal includes feedback to modify the injections as decades pass and observations are gathered about the effect of the aerosols). The paper says “We do not claim that this scenario is optimal. Rather we claim that good-quality policy-motivated scientific analysis requires an explicit scenario, and that this scenario is less obviously suboptimal than some scenarios employed in the literature.” They point out that the harms of global warming increase superlinearly with temperature change, so I think they are saying that avoiding half the warming, or at least slowing global warming by half, is a reasonable compromise that avoids the worst harms without turning global warming into a total non-issue.
“Temporary deployment does not reduce long-term climate change. Warming in 2300, for example, is almost completely determined by cumulative carbon emissions and is unaffected by SRM that ends in 2200. Some commentators conclude that such temporary SRM offers no benefits, suggesting that it must be maintained forever.” The paper counters that many climate change impacts depend on the rate of change—that if warming is slowed down, it is less harmful even if the total warming over 200 years is left the same. So I think the proposal here is to taper off the aerosol injections in such a manner that, in the worst case, we get the same warming over 200 years rather than 100.
They note that “It is clear that this scenario does not directly address thresholds that are a function only of the magnitude of the change rather than the rate, although it does delay reaching these thresholds, giving more time both to learn about the system and develop alternate strategies.” The total amount of warming in their scenario *would* be decreased if we invent and deploy a technology that can remove CO2 from the air permanently (such technologies are very far from economical today). However, we can’t guarantee we will invent an economical technology to do this. If we don’t, Greenland may still melt under their scenario, but later than it would have otherwise (“in Fig. 1, the time to reach a temperature rise of 2 °C above pre-industrial increases from 2055 to 2068, while the time to reach a 2.5 °C rise increases by 32 years.“).
Regarding stoppage of geoengineering due to catastrophe, they say, “While not discounting the possibility of social collapse, we note that humanity has operated technologies such as trans-oceanic communication links and electric power grids for more than a century in spite of horrific wars. Moreover, in considering the implications of a possible social collapse on the public policy of SRM [Solar Radiation Management], one must set the risks of termination against the (likely) greater human suffering that would arise directly from the collapse itself.” So, if there’s a global catastrophe, a sudden increase in global warming seems like a minor footnote in comparison.
I remain concerned that geoengineering is a distraction that could reduce the pressure to reduce CO2 emissions, but if geoengineering were to become a popular political position, I agree that Keith & Macmartin’s proposal seems better than the “default” geoengineering proposal that people (including me) naively think of, i.e. to simply stop global warming regardless of CO2 emissions.
Additional objections to stratospheric aerosol injections:
1. Stratospheric aerosol injections will stop global warming but not ocean acidification, which is caused directly by CO2 dissolving in seawater. This is a notable consequence if this “plan B” disrupts the “plan A” to reduce our carbon emissions to zero or below.
2. Once (conventional) aerosol injections start, they must not be stopped. Explanation:
I think it’s fair to say that the main danger of global warming is its speed: ecosystems and human civilization would perhaps barely notice if the global mean land temperature were to rise 3°C gradually over the course of 10,000 years, but the same change in 100 years is difficult to bear (trivia: climate models and recent temperature records all agree that land temperatures will rise faster than sea temperatures; they disagree as to the extent of this phenomenon but, long story short, if global temperatures rise 2.2°C this corresponds to about 3°C warming on land, or more in the short term. I think that the goal to “keep global warming under 2°C” rather than “under 5°F on land” was a bit of a marketing mistake. Details in this paper.)
Stratospheric aerosols fall out of the stratosphere after a year or two, whereas much of our CO2 emissions will stay in the atmosphere for hundreds of years. Once stratospheric aerosol injections begin (assuming net CO2 emissions remain above zero), the quantity of aerosols must be continually increased to maintain a roughly constant temperature.
If the injections are ever suddenly stopped, most of the warming that would have occurred, over the decades or centuries that injections have been done, will occur immediately. This extremely rapid change is potentially very disruptive to humanity and global ecosystems, so an injection program should not begin without a very high confidence that we can ensure the injections will continue in perpetuity.
3. It may already be too late to avoid this problem, but in case of a global catastrophe, where modern society and most of its technology disappears for some reason, we’ll want to rebuild society afterward. To this end, it may be significantly easier to rebuild if there is some oil left in the ground that is accessible to the reconstruction effort.
I sure am curious why you repeated the same comment four times (in addition to a couple of closely related comments) and why 100% of your comments on this site are on this page. It seems obviously inappropriate.
Based on Habryka’s point, what if “stage 1b” allowed the two reviewers to come to their own conclusions according to their own biases, and then at the end, each reviewer is asked to give an initial impression as to whether it’s fund-worthy (I suppose this means its EV is equal to or greater than typical GiveWell charity) or not (EV may be positive, but not high enough).
This impression doesn’t need to be published to anyone if, as you say, the point of this stage is not to produce an EV estimate. But whenever both reviewers come to the same conclusion (whether positive or not), a third reviewer is asked to review it too, to potentially point out details the first reviewers missed.
Now, if all three reviewers give a thumbs down, I’m inclined to think … the applicant should be notified and suggested to go back to the drawing board? If it’s just two, well, maybe that’s okay, maybe EV will be decidedly good upon closer analysis.
I think reviewers need to be able (and encouraged) to ask questions of the applicant, as applications are likely to be have some points that are fuzzy or hard to understand. It isn’t just that some proposals are written by people with poor communication skills; I think this will be a particular problem with ambitious projects whose vision is hard to articulate. Perhaps the Q&As can be appended to the application when it becomes public? But personally, as an applicant, I would be very interested to edit the original proposal to clarify points at the location where they are first made.
And perhaps proposals will need to be rate-limited to discourage certain individuals from wasting too much reviewer time?