Friday, June 20, 2014

Why thorium reactors are important

This post is the first of a series of posts that I've been wanting to write for a long time, but I haven't been able to pick from among the collection of topics that I wanted to write about. After taking a quick vote on what people actually want me to write about, this one got the most votes, so you get to read about why I think that we (as a society) should take hurcluean efforts to get liquid fluoride thorium reactors available as quickly as possible.

Disclaimer: before you invest $1 on what I say below, think, read, and verify.

Doom and gloom

Climate change is happening: 97% of climate scientists agree. The single best thing that we can do to address climate change is to substantially reduce our production of greenhouse gasses, which at present is primarily in the form of exhaust from the burning of fossil fuels. The problem is that fossil fuels are used as an energy source in our transport and electric grid, the combination of which allows for the efficient transport of people and goods, and allows for the supporting of a modern energy-consuming society (lights, heat, computers, communication, ...).

In order to truly replace fossil fuels, we must find a power generation technology that can be put in locations where both small to large power generation facilities already exist, and where we can replace the most polluting of vehicular transport (large transport ships). Cars like the Tesla, and those evolved from Tesla's patents will be available in the coming years, and we can put highways underground, keep people out of them, and use automated vehicular transport. Think automated Uber. Then you get 4-6x the vehicle density per lane, and adding lanes doesn't make traffic worse. :D

This requires power generation in the 10 megawatt - 10 gigawatt range, if we are looking to cover up to the current largest fossil fuel and current technology nuclear reactors. I'll explain why replacing current nuclear technology is important later.

Now enters a challenger

Liquid fluoride thorium reactor technology was first developed in the 1950's by a group at General Electric that were tasked with coming up with a nuclear generator that could be placed in an airplane, which was followed up by mostly the same group of people working at the Oak Ridge National Lab in the mid/late 60's. They ended up with a thorium-based technology that uses molten fluoride salts to carry the nuclear material (addressing partial burns, structural breakdown of fuel, ...), which allows for a 96%+ burning of the fuel - compared to the 1-5% efficiency of the best traditional nuclear reactors available today (quoted numbers vary from 1-2% to 3-5% for current tech, so I'm using the full range). One other feature is that you can introduce other spent nuclear fuels that are currently stored at hundreds of sites all over the world, and you can burn it. Yep, thorium plants can recycle nuclear waste.

One convenient win is that with proper work, there is no reason why liquid fluoride thorium reactor technology can't be scaled from smaller 10-20 megawatt reactors that can be sealed and buried for zero maintenance for a decade or more for small municipalities (though this wouldn't happen for a while, the economics need to make sense), up to replace the horribly polluting 90 megawatt-equivalent diesel engines in large ships (we'll need more nuclear engineers), to arrays of reactors for 10+ gigawatt power generation stations near our mega cities.

Why replace current reactor technology?

While "modern" reactors are generally safe (though there are several unsafe reactors currently being used around the world), the ugly part of current reactor technology is a combination of fuel efficiency and waste. There is immense amounts of energy stored in refined nuclear fuels, and with only 1-5% of that fuel being burned with current nuclear technology, you are left with a massive amount of waste that will be dangerously radioactive for the next 10,000 years or more. It is a scary problem, and thorium is a solution.

This nuclear waste storage problem is not going away. The only way we can really address the issue is to stop using current nuclear technology and find another solution. I claim that liquid fluoride thorium reactor technology is the best option we have right now, as not only can it actually generate the power we need economically (we need roughly 400 tons of thorium ore to power all of the energy needs of the US for one year, and there are 160,000 tons of ore that is economically accessible at current thorium prices), but it can burn the wastes that we need to get rid of in the long term anyway.

And the vast majority of the waste is generally considered safe in 300 years, compared to 10,000+ for typical reactors.

Why not solar/wind/hydro?

The technologies behind solar, wind, and hydro generation are all great, and wonderful, and they work. And it even turns out that the largest power generation stations in the world are hydro-electric plants. The major problem with these technologies is that they are difficult to scale. Specifically, we've more or less tapped the majority of the reasonably usable hydro power available, and the environmental fallout of flooding land is not always worth the power generated.

Solar is great (I was just looking into the cost viability of installing solar panels on my house), but it requires a large amount of land to be viable, and the cost of production is still high. Solar also has a nasty cousin, typically coal or natural gas power plants that support the grid when the sun isn't shining. When looking at thermal solar plants (instead of photovoltaics), you get the option for storing the heat for release at night, but thermal solar plants are still rare, and my research suggests that only one solar plant in the US has heat storage (in molten salt). Finally, the land and financial cost make solar difficult to scale up to utility-level requirements (currently maxing out at roughly 500 megawatts), and make it essentially unusable as a mobile power generation method for commercial transport ships (you can check out The Guardian's article on shipping pollution for why this is necessary).

Wind is also great, but there are limited locations where it makes sense, and there are political challenges with locating windmills near occupied land. It's also not a mobile technology, so is not viable for addressing the container ship problem. Wind power also has all of the same problems with consistency as solar without the simple heat storage method of thermal solar.

Ultimately, what we don't need is more "bursting" power sources that require secondary generation technologies, and which partially compromise the overall environmental benefit of using renewable sources like wind and solar.

What about fusion?

There have been recent reports that hydrogen-fusion based nuclear plants are now to the point where there are obvious paths of research and development that will lead directly to commercially viable power generation in the next 10-20 years. This is wonderful, but it is still all theoretical. The research isn't done, so the opportunity doesn't yet exist. These types of plants are also of the form that they only make sense to build huge plants, which makes manufacture of the plants a difficult investment, but also prevents the reactors from being mobile.

That's not to say that we couldn't end up in a future world where fusion power is available as a standard on-land reactor technology, while huge ships (shipping, navies, etc.) run thorium plants. But given the current state of technology, and how little money (relatively speaking) is being spent on thorium generator technology, there are some early and obvious wins that can be had by investing in thorium today, while the long-term benefits of fusion power are still attainable and can be developed on a parallel path.

But cars!

Cars will go electric with batteries. Think an entry-level Tesla. Also think battery swap technology for sub 5-minute recharges. We just need to make the technology cheap enough to be available to everyone. With Elon Musk releasing Tesla's patents, this is possible!

Long term destination

One of the reasons why I really like the idea of liquid fluoride thorium reactor technology is that it is the first obvious step towards reduction/elimination of fossil fuel use. That solves our short/mid-term global warming problem. But it also solves our mid-long term power problem when we finally get around to putting people on other planets in our solar system.

I know, I'm getting a few decades ahead of things here, but if we have any chance in hell of having a viable settlement on *any* other planet in this solar system (never mind in another solar system), we need a compact and efficient power generation technology whose fuel can be found on other planets. Thorium is available on the Moon, Mars, and Mercury, which are the three most likely locations for an off-world human settlement with current or soon-available technology. No, solar isn't enough (especially on Mars, which gets significantly less sunlight that we get here on Earth).

To make our lives even easier, we can actually detect whether a planet has available thorium, how much, and where it is located. And we can do this from space. Yes, we can scan for thorium from space. With current technology. Could thorium get any better?

Why isn't it done yet?

The simple answer is because insufficient time and money have been spent to make it commercially viable. There are various historical, political, and strictly human reasons for this. From it not being usable for generating materials usable in nuclear weapons, to it not being preferred by the guy who decided to use uranium-based reactors in the US navy's largest ships, to it being a different technology than the currently understood standard nuclear technology. These are all valid excuses, but that doesn't mean that we can't go beyond these excuses and make it happen.

It also doesn't mean that we can't move past these excuses and realize that the ultimate destination of a clean and readily available power source is within our grasp! Not in 50 years, but easily within 5 years for a test reactor, and 10 years for a serious commercial reactor in the gigawatt+ range. The challenges for the liquid fluoride thorium reactor design are strictly of the materials science, chemistry, regulatory, and investment kind. And guess what? The materials science and chemistry part have been worked on for the last half-dozen+ years, and are effectively solved. Whether or not regulators and investors are willing to make it happen is what is the real question.

Some detractors will claim it's still 40-70 years out, but to them I would just point out that the original nuclear reactors didn't take 40-70 years from conception through design, test reactors, and final construction. From first commissioning of the design for the USS Nautilus in December 1949 until it sailed under nuclear power in January 1955, there were barely more than 5 years of concentrated effort to go from the order to design it to it being built and used to travel farther and faster underwater than any other submarine before.

There are also several world governments that are working on thorium-based liquid salt reactor technology, among which include: USA, China, Australia, Czech Republic, Russia, India, and the UK. It's going to happen, and it can't happen soon enough. What is $10 billion in the next 5-10 years if it means that everyone would have access to inexpensive, clean, life-altering electric supply. With electricity, you have water. With water, you have food, trees, and can bring more rain for more water. It is an amazing virtuous cycle, and can start reversing the CO2 levels in our atmosphere *now*.

Which, incidentally, might very well be the most important thing that we can do if we want to avoid a global drought. It is scary stuff, and we need to reforest the planet yesterday. This gets us there globally, and will teach us what we need for when we try to terraform Mars in the next 30-40 years. If we make an effort, we could seriously be living on Mars in our lifetimes.

Where can I get more information?

First off, watch this hour-long video: Dr. Joe Bonometti explains Thorium. That should give a pretty broad overview of what is going on with the history, economics, etc., of the reactor technology, and it includes a link to Energy From Thorium. Generally, I like most of the information provided on the site, but there are several articles that I've read there that are a long way from being professional enough from an advocacy perspective. Also, there seems to be more interest in raising awareness rather than actually doing things (like getting a reactor built and used).

A group of MIT graduates at Transatomic Power have been working on liquid fluoride thorium reactor technology for a few years now and have released a whitepaper describing their design in detail. I don't know their funding situation, or what sorts of regulatory challenges they are facing, but they do have a collection of experienced advisors helping them.

Another group has been working for and advocating the design at Flibe Energy for several years now, and are targeting the military base market, which seems to offer a potential bypass of both the investment and regulatory issues that may be blocking other efforts. They've also got a collection of great advisors and top-notch founding team members. They haven't released their design, but I think it would be foolish to believe that they haven't at least looked at Transatomic Power's design for ideas and possible improvements.

There are also links and information from one of a dozen different Wikipedia pages, for individual thorium reactors, including existing molten salt thorium reactors, information about companies, etc. Start from the page on Liquid fluoride thorium reactor and follow the links

What can you do?

Unfortunately, I don't have a list of things that you can do to help in the advancement of liquid fluoride thorium reactor technology. Heck, in writing this article I'm hard-pressed to find something for *me* to do beyond just writing a general advocacy and quick overview of why I think that thorium is the future. But as a start, we can become educated about what is going on, and attempt to understand and spread the fact that there are no other technologies that could offer such a change in energy generation technologies in such a short timespan. Nothing.

Update:

Okay, thanks to Eric Snow, from the comment, I have just learned about a potentially viable fusion reactor technology. This is what could get us there too (thorium is still viable for helping to burn up old nuclear waste, so keep looking and reading). First, read this article on Gizmag, and then go here to donate. I donated last night. And then I just read this article, which was written May 31, 2014: Record setting temperatures of roughly 1.0 - 1.8 billion degrees kelvin. This could happen people.

2 comments:

  1. +1

    Also, have you seen lawrencevilleplasmaphysics.com?

    ReplyDelete