Posts Tagged ‘green energy’
the thorium fuel future, or not…
So what about thorium as part of our clean energy future? Are there any thorium reactors operating? How do they work? How do they compare to uranium-based reactors?
Well, there appear to be a lot of plans on drawing boards, for good reason, it seems. Thorium is about three times more abundant than uranium, and is potentially a safer source of nuclear energy, which, ironically, is largely why it was overlooked early on, due to uranium’s far greater weapons potential. To quote Wikipedia,
The Thorium Energy Alliance estimates “there is enough thorium in the United States alone to power the country at its current energy level for over 1,000 years.”
When used in a liquid fluoride thorium reactor (LFTR), a type of molten salt reactor (MSR), far less nuclear waste results. And there are many other positives. An estimate by Nobel Prize-winning physicist Carlo Rubbia, for example, that a ton of thorium can produce the energy of 200 tons of uranium and three and a half million tons of coal.
And there’s more stuff about thorium’s advantages that sound just too good to be true. Wikipedia lists nine positives in bullet points. However, there are substantial start-up costs, and there are problems with ‘breeder reactors’ and proliferation, which I’ll try to understand later.
Reading the story of uranium v thorium from the late forties into the seventies, you can clearly see that the military side of the military-industrial complex, especially in the USA, won out at the expense of safe commercial and domestic energy use. But what with the recent urgency about alternatives to fossil fuels, and the concern (methinks largely unwarranted) about uranium-based nuclear, thorium is inching its way back into favour. Sabine Hossenfelder reports on its soon-to-be-arrival in Europe while castigating the German state’s pulling the plug on nuclear in general (Steve Novella of the Skeptics’ Guide is also bemused). I reckon they’re gonna change their changed mind eventually.
Anyway, the news is that the Netherlands and France, two countries that embrace nuclear power, have teamed up to bring small thorium reactors to Europe. NAAREA, a French alternative energy company, and Thorizon of the Netherlands, have combined their smarts and funds, and I’ll quote Sabine:
NAAREA is already working on small nuclear reactors, and they want to combine their technology with the thorium cores from the Dutch.
This is the concept of small, transportable nuclear reactors that I first read about in Steven Pinker’s Enlightenment Now some years ago. The fact is, though, that progress seems to be slow in this field, in spite of all the global warming concerns. NIMBYism is still a problem, as well as whole of government negativity, as in Germany. Nations that are more keen are India, which has the world’s largest thorium reserves, China, Canada and the USA.
So what about here in Australia? We have actually banned nuclear energy, both federally and in every state and territory, and there appears to be no appetite for changing the situation. This also means there’s no avenue for those interested in nuclear energy and its engineering and technical requirements to gain expertise in the field here. I suspect the only factor that will change our governmental (and popular) mindset will be the proven success of new thorium-based reactors elsewhere. Of course, Australia has the perfect climate for solar and storage, so there’s little appetite for changing direction – though it should be noted that Australia ranks with the USA as having the third largest reserves of thorium, behind India and Brazil.
So how does thorium work as a nuclear fuel? I’ve no idea, so here goes with another particle of my lifelong learning. First, to the World Nuclear Association. Three points:
- [Thorium] is fertile rather than fissile, and can only be used as a fuel in conjunction with a fissile material such as recycled plutonium.
- Thorium fuels can breed fissile uranium-233 to be used in various kinds of nuclear reactors.
- Molten salt reactors are well suited to thorium fuel, as normal fuel fabrication is avoided.
The first point is sort of self-explanatory – thorium nuclei (232) can’t be split apart by ‘thermal neutrons’ (neutrons travelling above a certain velocity), but they can be converted into fissile material via ionising radiation. The nuclei may then capture neutrons and be converted to fissile material (uranium-233, in the case of thorium).
The third point obviously needs some explaining. The reactors used to generate thorium-based energy are called liquid fluoride thorium reactors (LFTRs), which are:
a molten salt type of reactor [MSR], meaning that the fuel inside the core is actually in a liquid form in a salt formation that circulates inside the core. It is hot and acts as a fuel and coolant at the same time, meaning that the heat from this liquid fuel that is circulating inside the core is being transferred to the heat exchanger and to the rest of the components and electricity is produced similarly to any other type of reactor.
Elina Charatsidou (see references)
That’s a start. The differences between this type of liquid fuel and the highly structured solid fuel rods create both advantages and disadvantages…
So, as mentioned, thorium-232 is quite abundant and, unlike uranium-235, it isn’t fissile (which makes it similar to uranium-238), but its ‘fertility’ allows it to capture neutrons, so transmuting into protactinium-233 which then decays into uranium-233, which is fissile. This, I think, is the important point. It’s the splitting of the uranium-233 that produces the efficient energy, not thorium itself. And Elina points out something I don’t quite understand as yet – ‘there are 2 ways that can be produced – uranium-233 can be produced inside the core, or outside and then placed inside the core as a fuel for the thorium reactors’.
Ultimately, though Elina Charatsidou and other informed commentators aren’t quite buying into the hype of some about a thorium future. It should be developed, and it’s needed as our population continues to grow and, more importantly, become more prosperous. We need to get behind it as part of a multi-faceted approach to our energy future.
For a more positive spin on thorium and new developments in nuclear energy, especially regarding storage, re-use, corrosion and cost factors, as well as issues around public-private ownership, the Copenhagen Atomics video, linked below, is well worth a look.
References
https://en.wikipedia.org/wiki/Thorium-based_nuclear_power
Good News: Small Nuclear Thorium Reactors are Coming to Europe (Sabine Hossenfelder video)
Steven Pinker, Enlightenment Now, 2018 (pp146-9)
https://world-nuclear.org/information-library/current-and-future-generation/thorium.aspx
our electric future – is copper a problem?
So I recently had a conversation with someone who told me that electric vehicles were not the future because – copper. I must admit that I immediately got tetchy, even though I knew nothing about the ‘copper problem’, or if there actually was one. My interlocutor wasn’t anti-green in any way, he was more into electric bikes, tiny-teeny cars, and people staying put – not travelling anywhere, or not far at least. Perhaps he imagined that ‘virtual travel’ would replace real travel, reducing our environmental footprint substantially.
It has struck me that his rather extreme view of the future was an example of the perfect being the enemy of the good. I’m all for electric bikes, car-sharing and even a reduction in travelling, within limits (in fact migration has been associated with the human species since it came into being, just as it has with butterflies, whales and countless other species) but although I note with a certain disdain that family cars are getting bigger just as families are getting smaller (in our WEIRD world), I have no faith whatever that those family cars are going to be abandoned in the foreseeable.
But getting back to copper, the issue, which I admit to having been blind to, is that with a full-on tilt to electrification, copper, the world’s most efficient and cheaply available electric conductor, might suddenly become scarce, putting us in a spot of bother. But will it? That depends on who you talk to. Somehow the question brings back to mind David Deutsch’s The beginning of infinity, a super-optimistic account of human ingenuity. Not enough copper? No problem we can’t engineer our way out of…
Currently demand for copper is outstripping supply, but will this be a long term problem? CNBC made a video recently – ‘Why a looming copper shortage has big consequences for the green economy’ – the title of which, it seems to me, is more pessimistic than the content. Copper has been an ultra-useful metal for us humans, literally for millennia. But its high conductivity – second only to silver, which presumably is more rare and so far more expensive – has made it the go-to metal for our modern world of electric appliances. It also has the benefit of being highly recyclable, so it can be ripped out of end-of-life buildings, vehicles and anything else and re-used. But EVs use about four times more copper than infernal combustion vehicles, and wind turbines as well as solar panels require lots of the stuff, as do EV charging stations, and there aren’t too many new copper mines operating, so…
From what I can gather online, though, there’s no need for panic. Apparently, we’re currently utilising some 12% of what we know to be available for mining. The available stuff is the cheap stuff, and until now we’ve not really needed much more. But new techniques of separating copper from its principal ore, chalcopyrite, look promising, and markets appear to be upbeat – get into copper, it’ll make your fortune!
There’s also the fact that, though things are changing, the uptake of EVs is still relatively slow. People are generally talking about crunch time coming in that vaguely defined era, ‘the future’. High copper demand, low supply seems to be the mantra, and all the talk is about investment and risk, largely meaningless stuff to impoverished observers like me. In more recent times, copper prices have dropped due to ‘a manufacturing recession caused by the energy crisis’. I didn’t know about either of these phenomena. Why wasn’t I told? Mining.com has this to say about the current situation, FWIW:
Copper prices typically react to the ebb and flow of demand in China, which accounts for half of global consumption estimated at around 25 million tonnes this year. But this time the focus is on Europe, accounting for 15% to 20% of the global demand for copper used in power and construction. The region is facing surging gas and power prices after energy supply cuts, which Russia blames on Western sanctions over the Ukraine conflict. The European Union has made proposals to impose mandatory targets on member countries to cut power consumption.
Make of this what you will, I have quoted the most coherent passage in a mire of economics-speak. Presumably, supply is affected by the volatile conditions created by Mr Pudding’s testosterone. So everybody is saying that copper is falling in price, and this is apparently bad. Here’s another quote to make sense of:
Due to closing smelters and falling demand from manufacturers, an excess of copper stockpiles has been building up in a number of Shanghai and London warehouses, also contributing to downward pressure on prices.
Meaning copper isn’t worth much currently, though this is probably a temporary thing. Glad I haven’t anything to invest.
I think the bottom line in all this is don’t worry, be happy. Copper availability for the energy transition is subject to so many incoherent fluctuations that it’s not worth worrying about for the average pundit. Here in Australia the issues are – you can solarise your home no worries. Buying an EV is another matter, since none are being manufactured here, so governments need to be pressured to create conditions for a manufacturing base, and the infrastructure to support the EV world. Storage and battery technology need to be supported and subsidised, as is in fact starting to happen, with a more supportive federal government, and state Labor governments here in South Australia, and in Western Australia, Queensland and Victoria.
So, to conclude, having read through quite a few websites dealing with copper as the go-to metal for the transition to green energy (some links below), I haven’t found too much pessimism or concern about Dr Copper’s availability, though there are clearly vested interests in some cases. Australia, by the way, has the second largest copper reserves in the world (a long way behind Chile), and this could presumably be turned to our benefit. I’m sure a lot of magnates are magnetised by the thought.
References
https://oilprice.com/Energy/Energy-General/A-Copper-Crisis-Threatens-The-Energy-Transition.html
https://intellinews.com/ev-market-may-create-copper-deficit-219864/
some more on hydrogen and fuel cells
an electrolyser facility somewhere in the world, methinks
Canto: Our recent post on democracy and public broadcasting has made me turn to PBS, in order to be more democratic, and I watched a piece from their News Hour on clean hydrogen. Being always in need of scientific education, I’ve made this yet another starting point for my understanding of how hydrogen works as an energy source, what fuel cells are, and perhaps also about why so many people are so skeptical about its viability.
Jacinta: Fuel cells are the essential components of hydrogen vehicles, just as batteries are for electric vehicles, and infernal combustion engines are for the evil vehicles clogging the roads of today, right?
Canto: Yes, and Jack Brouwer, of the National Fuel Cell Research Centre in California, claims that fuel cells can be designed to be just as fast as battery engine. Now according to the brief, illustrated explanation, diatomic hydrogen molecules enter the fuel cell (hydrogen occurs naturally in diatomic form, as does oxygen). As Miles O’Brien, the reporter, puts it: ‘A fuel cell generates electricity by relying on the natural attraction between hydrogen and oxygen molecules. Inside the cell, a membrane allows positive hydrogen particles [basically protons] to pass through to oxygen supplied from ambient air. The negative particles [electrons] are split off and sent on a detour, creating a flow of electrons – electricity to power the motor. After their work is done, all those particles reunite to make water, which is the only tailpipe emission on these vehicles.’
Jacinta: He tells us that the oxygen is supplied by ambient air, but where does the hydrogen come from? No free hydrogen. That’s presumably where electrolysis comes in. Also, membranes allows protons to pass but not electrons? Shouldn’t that be the other way round? Electrons are much tinier than protons.
Canto: Very smart. Maybe we’ll get to that. Brouwer talks of the benefits of fuel cells, saying ‘you can go farther’, whatever that means. Presumably, going farther with less fuel, or rather, you can have a lot of fuel on board, because hydrogen’s the lightest element in the universe. Clearly, it’s not so simple. O’Brien then takes us on a brief history of hydrogen fuel, starting with the conception back in 1839, and real-world application in the sixties for the Apollo missions. The Bush administration pledged a billion dollars for the development of hydrogen fuel cell cars in the 2000s, but – here’s the problem – they were producing hydrogen from methane, that infamous greenhouse gas. Ultimately the cars would be emission free and great for our cities and their currently dirty air, but the hydrogen production would be a problem unless they could find new clean methods. And that’s of course where electrolysis comes in – powered by green electricity.
Jacinta: The splitting of water molecules, a process I still haven’t quite got my head around….
Canto: Well the PBS segment next focuses on the sectors in which, according to Brouwer, hydrogen fuel will make a difference, namely air transport and shipping. Rail and heavy vehicle transport too – where the lightness of hydrogen will make it the go-to fuel. It’s energy-dense but it must be compressed or liquefied for distribution. This makes the distribution element a lot more expensive than it is for petrol. So naturally Brouwer and others are looking at economies of scale – infrastructure. The more of these compressors you have, the more places you have them in, the cheaper it will all be, presumably.
Jacinta: Right, as presumably happened with wind turbines and solar panels, and the more people working on them, the more people coming up with improvements… But how do they liquefy hydrogen?
Canto: Hmmm, time for some further research. You have to cool it to horribly low temps (lower than −253°C), and it’s horribly expensive. There was a bipartisan infrastructure bill passed recently which will fund the building of hydrogen distribution hubs around the USA through their Department of Energy. That’s where the action will be. The plan, according to mechanical engineer Keith Wipke of the National Renewable Energy Laboratory, is to do in ten years what it took solar and wind 3 or 4 decades to achieve. That is, to bring hydrogen production costs right down. He’s talking $1 per kilogram.
Jacinta: Okay, remember that in 2032.
Canto: Yeah, I won’t. They’re talking about improving every aspect of the process of course, including electrolysers, a big focus, as we’ve already reported. They’re connecting these electrolysers with renewable energy from wind and solar, and, in the bonobo-science world of caring and sharing, any new breakthroughs will quickly become globalised.
Jacinta: Yeah, and Mr Pudding will win the Nobel Peace Prize…
References
Could hydrogen be the clean fuel of the future? (PBS News Hour video)
green hydrogen? it has its place, apparently