Jun 13 2024

Bill Gates Backs Nuclear

No one ever said that nuclear power is simple or easy. It’s a tricky and expensive technology. But it also has tremendous potential to create large amounts of reliable green low carbon energy, and many believe that we cannot ignore this potential if we are going to tackle climate change. Billionaire Bill Gates is one of those people.

In the US, since around 1990, we have generated about 19% of our electricity from nuclear power plants. Nuclear produces about 10% of the world’s power from 440 plants. The average age of a nuclear power plant in the US is 42 years – these plants were designed with a 40 year life expectancy. There have been three plants to go online this century, and the last one before that was completed in 1996 – with a 20 year gap with no new nuclear. The bottom line is that we have not been maintaining our expertise in nuclear reactors. Now we are trying to make up for lost time, but find ourselves far behind.

There are several challenges (this list is not meant to be exhaustive) – the cost of building large nuclear power plants, safety issues, sourcing the fissile material, and storing spent nuclear fuel. But there are also lots of advantages – safe reliable green power, predictable (not variable) power, and a small land footprint. Further, we can choose to build nuclear power plants on existing coal fired plant sites. This also has several advantages – the new plant can use existing connections to the grid, will minimize the economic impact to the community of shutting down a job source, and much of the site work is already done.

While wind and solar are great renewable energy sources, they have their own challenges – they use a relatively large amount of land for the amount of power produced, they require lots of upgrades and extensions to the grid, and they are intermittent. I see the two energy sources as complementary. Put solar on roofs, put wind where it is optimal, and replace existing coal plants with nuclear plants while maintaining our existing nuclear fleet.

The challenge is this – how do we revitalize our nuclear industry to make it more modern and competitive? It will require lots of that universal resource, the resource that makes all things possible, money. This is the reason the IRA includes subsidies for new nuclear, to kickstart the process of ramping up and modernizing our nuclear industry. This is also where Bill Gates comes in. What I describe sounds like exactly how he sees things, and he understands that making new nuclear feasible requires deep pockets to absorb the short term costs. He is willing to be those deep pockets.

He is doing this through a company called Terrapower. They are building their first plant in Wyoming, near the site of a coal-fired plant that is being retired.  The plant has two main design innovations intended to make it more cost effective. The first is that it uses molten salt rather than water to cool the reactor and transfer heat to the turbine. This allows for much lower pressure and the molten salt also will cool faster on its own. Avoiding the need for high pressure can be a significant cost saving and would make the plant much safer.

The molten salt design also has another huge advantage over older designs – it makes it easier to ramp up or down the power output of the entire plant, so that it can combine better with intermittent sources. In fact, energy can be stored in the molten salt when it is not needed, and then sold to the grid when demand spikes or intermittent sources wane. This plant design therefore can help stabilize the grid.

The second design change is to separate the part of the plant that produces heat – the nuclear reactor – from the turbine that makes electricity. The molten salt is transported from one building to the other to transfer the heat. Separate these buildings means that the turbine part of the plant does not need all the safety measures that the nuclear reactor part requires. That, at least, is the theory. The Nuclear Regulatory Commission still needs to sign off on this design.

But these are great examples of the kinds of innovations that can make nuclear safer, more nimble, and more cost effective. The plant is also smaller than traditional large nuclear power plants, which also reduces the upfront costs.

I have to say, as billionaires go, I am impressed with Gates. I admired his charity work for a long time, and his stated goal to “vaccinate the world”. He has shrugged off the conspiracy theories from the tin-hat brigade, and has just plugged along trying to make the world a better place. He is doing that now, and I think he gets the issue exactly right. He says:

“Wind and solar are absolutely fantastic, and we have to build them as fast as we can, but the idea that we don’t need anything beyond that is very unlikely,”

He also understands his role in this:

“We’re taking that risk, which, because of our design, we feel very good about,” Mr. Gates said. “But it means you need very deep pockets.”

The plant is scheduled to come online in 2030. We need a hundred more similar plants. We also need to continue to innovate and improve the designs so that nuclear is more competitive and integrates well into the future grid. At the same time we also need to redevelop domestic sources of fissile material. We allowed Russia to corner that market, and that may not be sustainable in the current geopolitical climate. We also need federal regulation for long term spent fuel storage, to end the NIMBYism that has hampered such projects so far.

On a side note, because this always comes up, spent nuclear fuel is not the deal-killer many make it out to be. First, the highly radioactive materials have a short half-life – by definition. Half life and intensity are inversely related. The very long half-life materials, the ones that need to be stored for thousands of years, are near background radiation levels. Further, if we wanted to, we could reprocess much of this spent fuel into new fuel for modern reactors. In the meantime, we just store it.

All of the issues with nuclear power are solvable, and it is becoming increasingly clear that we may not have any other choice if we are going to avoid the worst of climate change. This is especially true as our electricity demand is rapidly growing, even faster than previous estimates. All those AI data centers need lots of power. The only solution is the “all of the above” approach, and that includes nuclear. The advantages I listed above just can’t be ignored.

If Bill Gates, who seems to agree with all this, is successful, this may be his greatest contribution to the world.

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