Mar 04 2019

Is There a Role for Renewables?

Michael Shellenberger has a provocative editorial in which he makes the case against renewables and for nuclear energy. At first you might think you are reading global-warming denial propaganda, but that’s not what it is. Shellenberger is a self-described ecomodernist who simply thinks that, if you look at the numbers, there is a strong case to be made for nuclear energy as the most practical solution to global warming.

I half-buy his editorial. I agree with everything he says about nuclear power, and have made the same points myself. Nuclear is the safest form of energy by far, and has the lowest environmental impact. It is also the only solution that will enable us to replace our existing fossil fuel infrastructure anytime soon. The alleged problems with nuclear are also overblown.

The typical points raised against nuclear are topped by – how to deal with the nuclear waste. There are two answers to this concern, however. The first is to simply deal with it. Approve waste disposal sites like Yucca Mountain and safely store the waste. The second solution, however, is even better – modern reactors can burn much of what is now considered waste, including waste from older reactors.

In fact, the definition of nuclear “waste” is flexible. It is simply nuclear material that we currently do not use as fuel in reactors. But it can be used as fuel – nuclear “waste” is just another form of nuclear fuel. We already have designs for nuclear reactors that can minimize waste, and even reduce existing waste, and what remains can easily be dealt with.

Another concern is that nuclear reactors are used to feed the production of weaponized fissible material. But this also does not have to be the case. In fact, this point and the previous one are related. It is true that current nuclear power plants were designed to produce “waste” that could then be used by the military to ultimately produce material for nuclear weapons. However, we can design plants as purely civilian, with a nuclear cycle that burns more of the nuclear material and does not create any weaponized material.

The other main criticism is that nuclear power plants are extremely expensive, and take a very long time to permit and build. This is partly just a political choice, however. We could streamline the process if we wanted to. Further, the nuclear industry is shifting to smaller cheaper power plants. The market thinks nuclear is too expensive – fine, they will make it cheaper.

The point is that none of the alleged problems with nuclear power is a deal-breaker. They are all practically solvable. There is no reason why we cannot have a safe, cost-effective, and environmentally friendly nuclear power infrastructure. In fact if you crunch all the numbers, this is the best option over the 21st century, and our best hope of limiting global warming.

Where I do not agree with Shellenberger is over renewable energy. He essentially does to renewables what nuclear critics do to nuclear – raise potential issues and then pretend they are unsolvable. His best point is that renewables such as wind and solar rely on intermittent sources that are not energy dense, and therefore require a lot of space. This is true, and is the ultimate limiting factor of these sources of energy. But they are not a deal-breaker.

The total surface area of the earth required to produce enough power through solar alone is not as much as you might think. By one estimate it would require an area of 496,805 square kilometers. This is not much if it is distributed around the world. Much of this could be on rooftops, and even if they are not optimally efficient could take a huge chunk out of that number. Then add solar farms in deserts and we can get there.

But keep in mind – this is for 100% solar production. I don’t think that should be our goal, at least not anytime soon. The way the energy industry works is that that they use the cheapest energy available as needed. They pick the low-hanging fruit, and then go higher only when they need to. In other words – we can pick the low-hanging solar fruit, and not worry about how to get to 100% production.

Shellenberger dismisses rooftop solar by saying that it is twice as expensive as a solar farm. Sure – if you have a perfectly positioned panel in the desert that will be more efficient than an average rooftop, that may have shading and be positioned not optimally. But here’s the thing – some rooftops may have good sun positioning and no shading, and be in a part of the country with lots of sun. That’s the low-hanging fruit. It is easy to obtain an analysis of the solar potential of your rooftop, and if it makes sense economically, solar could be a good option. But don’t put solar panels on a shaded roof facing the wrong way in a cloudy part of the country.

He glosses over the issue of grid storage, saying simplistically, “There won’t be a battery revolution.” Sure, but there is continued battery evolution. Battery and solar panel technology have been steadily and slowly improving, and give every indication that they continue to do so. For example, power companies in certain areas are finding that solar plus battery grid storage is a cheaper option for peak demand than building gas power plants. That’s huge. Once renewable and grid storage is a cost effective option, companies will use that instead of even natural gas (which is at historically low pricing). We are there, and it is only going to get better.

Right now we are at the point where renewables plus grid storage make sense and are cost effective in some (but not all) situations. Shellenberger is committing the nirvana fallacy, making the perfect the enemy of the good. Sure, solar is not the option for everywhere all the time – but there are places where it is the cost-effective choice.

The same is true of his other, perfectly legitimate, concern, that of disposing of solar panels that are past their prime. We do need to push the industry into using cheaper, abundant, and environmentally friendly materials so that the impact of the entire solar panel lifespan is minimized. And this is happening – the technology is progressing quickly and steadily. Investing in solar will keep the technology progressing.

The same is true of wind power. Shellenberger brings up problems with killing birds and bats. The answer to that is simple – don’t put wind turbines in areas where they threaten endangered animals. Put them offshore, and out of typical bird migration and hunting areas. Also, newer designs are safer for birds, and if we prioritize that feature can be made safer still. We don’t need to power the world with wind – but can put turbines where they make the most sense.

I get the feeling that Shellenberger would not accept the kind of criticisms for nuclear that he is giving against renewables. So he has not convinced me to abandon the position that we need a mix of energy sources. I am with him on nuclear energy – that is the best way forward (until we perfect fusion energy – however long that will take). We need to make nuclear a priority, rethink the red tape, produce smaller cheaper plants that use updated purely civilian cycles that minimize waste and optimize safety.

But at the same time we need to pick the low-hanging fruit of solar and wind energy, pairing them with the best grid storage for each location. We need to keep an eye on the unintended consequences, and then mitigate them. All the issues he raised are solvable, and are being solved. We have already crossed the line of cost-effectiveness and environmental-effectiveness in the right situations, and they get better every year.

All of these options are so much better than continuing to burn fossil fuels that we do need to push them forward as rapidly as possible. He correctly points out that the health benefits alone are worth it. Fossil fuels are a dirty old technology that we no longer need. We should transition away from them as quickly as possible.

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