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Are you interested in nuclear energy’s role in a carbon-free future?

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Our summary today works with the article titled Investigating the potential of nuclear energy in achieving a carbon-free energy future from 2023, by Janis Krümins and Maris Klavins, published in the MDPI Energies journal.

This is a great preparation to our next interview with Kirsty Braybon in episode 332 talking about nuclear energy and its regulatory framework.

Since we are investigating the future of cities, I thought it would be interesting to see another option, nuclear energy, in the energy mix for a carbon-free solution. This article discusses the role of nuclear energy, particularly small modular reactors in achieving a carbon-free energy future.

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Welcome to today’s What is The Future For Cities podcast and its Research episode; my name is Fanni, and today we will introduce a research by summarising it. The episode really is just a short summary of the original investigation, and, in case it is interesting enough, I would encourage everyone to check out the whole documentation. This conversation was produced and generated with Notebook LM as two hosts dissecting the whole research.

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Speaker 1: Today we’re tackling a really big question for our energy future nuclear power. It’s

Speaker 2: definitely a hot topic.

Speaker 1: This one zooms right in on a pretty debated solution.

Speaker 2: Exactly. We’ve dug into a detailed scientific paper that looks at nuclear energy from the big picture of decarbonization. So our aim here is to give you a clear rundown of the arguments why nuclear is even on the table. The big challenge is safety and waste. How it stacks up against renewables.

Speaker 1: Okay, so let’s set the scene first. The urgency, the paper really hammers home that climate change means we need serious cuts in greenhouse gases

Speaker 2: and electrifying sectors like transport and heating. That’s scene is a key strategy,

Speaker 1: but the reality check is where does our energy actually come from now?

Speaker 2: Yeah, that’s the kicker. The paper states, it’s still about 84% fossil fuels globally. Oil, coal, natural gas, 84%. Wow. So low emission sources, that’s hydro. Renewables like wind and solar and nuclear, they only make up about 16%,

Speaker 1: and global electricity demand keeps going up.

Speaker 2: It does, and the paper makes it pretty clear that right now, renewables alone, they just can’t reliably meet all that growing demand.

Speaker 1: So getting off fossil fuels is vital, obviously, but the paper also points out that even hitting net zero might not be enough to undo the damage already done,

Speaker 2: which is why we need to look seriously at all the low carbon options. That brings us squarely to nuclear.

Speaker 1: So what’s nuclear’s potential role here?

Speaker 2: According

Speaker 1: to the paper,

Speaker 2: its main advantage is providing stable, uninterrupted electricity base load power, they call it. And crucially, it does this without significant greenhouse gas emissions during operation.

Speaker 1: So it compliments renewables, which can be intermittent

Speaker 2: precisely. Think of it like the steady rhythm section in a band, while renewables are maybe the lead instruments that come in and out. The paper also highlights something newer. Small modular reactors, SMRs,

Speaker 1: not the giant plants we usually picture.

Speaker 2: Exactly. These are smaller, maybe up to 300 megawatts. A key thing is potential for enhanced safety features like passive cooling systems that don’t need active power to work. Which

Speaker 1: sounds like a big safety improvement

Speaker 2: potentially. Yes. Their smaller size means more flexibility in where they could be built.

Speaker 1: That adaptability seems important, like for remote areas or specific industrial needs

Speaker 2: could be. And the paper even mentions a really interesting idea using SMRs to power carbon capture systems.

Speaker 1: Oh, interesting. So tackling existing CO2 as well

Speaker 2: potentially. Yeah. It’s also worth mentioning quickly, there are different reactor types. The paper touches on light water reactors are the most common worldwide than boiling water reactors. A simpler design. And high temperature gas. Cool reactors or rich tgs.

Speaker 1: What’s special about those?

Speaker 2: They operate at much higher temperatures, which could make them more efficient for things beyond just making electricity.

Speaker 1: Yeah,

Speaker 2: producing hydrogen fuel.

Speaker 1: Okay. Interesting potential there. Now to make this more concrete, the paper uses Latvia as a case study. Why Latvia?

Speaker 2: Good question. Latvia currently imports a lot of its energy, so nuclear could offer energy independence, which is a big driver. Makes sense. Plus, it aligns with needing low carbon, reliable power. The paper suggests potential economic benefits too. Jobs growth, maybe even exporting electricity since their own demand isn’t huge,

Speaker 1: but there are always hurdles.

Speaker 2: Absolutely. The paper stresses that for Latvia or anywhere, you have to nail three things, safety first and foremost. Then a solid accepted plan for waste management, and finally, public acceptance. Those are the deal breakers.

Speaker 1: The paper also touches on just how we measure electricity. It’s not just what power plants produce,

Speaker 2: right? You have to factor in losses during transmission, electricity, you import electricity, you export. It’s like balancing a national energy checkbook to see what’s actually generated and consumed

Speaker 1: and getting that data right, must be tricky.

Speaker 2: It can be data collection methods vary, so comparing countries isn’t always straightforward. Consistency is key.

Speaker 1: Okay, let’s talk money costs. The paper looks at fixed costs, building the plant, land, regulations, and variable costs like fuel, labor

Speaker 2: maintenance. Yep. And it uses some 2020 IEA data to compare nuclear with coal, gas, hydro wind and solar costs are usually shown in dollars per megawatt hour.

Speaker 1: What did you take away from that comparison? Any clear winners?

Speaker 2: It’s complex. Nuclear generally has high upfront capital costs. Building the plane is expensive. But its fuel costs tend to be relatively low and stable over time and renewables. Solar and wind often have lower initial costs, sometimes much lower, but their total cost depends heavily on location, how sunny or windy it is, and you often need storage, which adds cost. Hydros in between on upfront costs, but very cheap to run day to day.

Speaker 1: How might SMRs change this cost picture? The paper mentioned potential benefits.

Speaker 2: That’s the hope, because they’re smaller and designed to be standardized. The idea is mass production could lower construction costs. Plus their flexibility might open up different markets,

Speaker 1: but it’s still early days for SMR costs

Speaker 2: very much. Most SMRs are still under development, so getting firm LCOE, that’s levelized cost of energy figures is tough. But yes, some estimates suggest they could be cheaper overall than the big traditional reactors. Still wait and see situation though.

Speaker 1: Okay, so thinking about decarbonization strategies overall cutting emissions from electricity, where does nuclear fit in?

Speaker 2: The core strategy involves renewables, obviously. But also things like carbon capture and storage CCS and just using energy more efficiently. Since nuclear produces zero carbon emissions while operating it directly helps with those decarbonization goals,

Speaker 1: right? You mentioned energy storage earlier. The paper sees that is pretty crucial.

Speaker 2: Definitely better, cheaper storage is needed to handle the ups and downs of renewables, and it can even help optimize how baseload power like nuclear is used. But the paper notes, cost and lack of standardization are still big hurdles for widespread storage.

Speaker 1: It briefly lists some storage types too, like lithium ion.

Speaker 2: Yeah, lithium ion lead, acid flow batteries, even compressed air storage. Each has its pros and cons. Cost, lifespan efficiency storage. Tech is evolving fast. We’re not quite there yet for grid scale needs everywhere.

Speaker 1: Let’s talk about performance, capacity factor and efficiency. How does nuclear measure up there?

Speaker 2: Okay, so capacity factor is basically how often a plant is actually running and producing power compared to its maximum potential.

Speaker 1: Like

Speaker 2: uptime. Exactly. And nuclear score is really high here. The paper sites averages around 90, 92%.

Speaker 1: Wow. That’s running almost constantly.

Speaker 2: Pretty much. Compare that to say solar PV at maybe 15, 25% or wind at 30, 45%, depending heavily on location and weather. This highlights nuclear’s reliability

Speaker 1: and efficiency. That’s different, right?

Speaker 2: Yeah. Efficiency is about how much energy in the fuel gets converted to electricity. Nuclear’s efficiency is actually similar to coal plants, maybe 33, 40 8%, much lower than hydro, which is super efficient, but higher than some renewables. It’s just a different metrics in reliability.

Speaker 1: Now, a big one, emissions the paper says zero emissions during operation. What about the whole process? Mining, construction, waste.

Speaker 2: Good point. The paper is clear. No, CO2 or greenhouse gases from the reactor itself.

Speaker 2: But yes, there are emissions associated with the full life cycle. Mining, uranium, enriching it, building the plant, decommissioning it, eventually managing the waste.

Speaker 1: But how do those compare?

Speaker 2: The paper emphasizes they’re generally low. It includes a table comparing lifecycle emissions. CO2, no anox, SO two per megawatt hour. Nuclear comes out way, way lower than coal or natural gas, and often comparable to, or even lower than some renewables, depending on the specifics.

Speaker 1: Okay, that’s important context. Let’s tackle safety directly. Public perception is often focused on accidents.

Speaker 2: Understandably, the paper acknowledges those concerns, but highlights the industry’s defense in depth approach. That means multiple independent layers of safety systems and physical barriers. Redundancy upon redundancy. Historically, major accidents at commercial plants like Chernobyl or Fukushima have been rare over decades of operation involving hundreds of reactors,

Speaker 1: and the paper mentions they can explode like a bomb.

Speaker 2: Crucially, yes, the fuel enrichment level in commercial reactors is far too low for a nuclear explosion. That’s a fundamental physics difference. The paper does note that human error has been a factor in past incidents, which is why training and safety culture are constantly being worked on.

Speaker 1: Okay, then there’s the waste. What does the paper say about managing that?

Speaker 2: It breaks waste down into categories, low level, intermediate, and high level, mainly based on radioactivity. Most of the volume is low level, but the high level waste contains most of the radioactivity. Even though it’s small in volume

Speaker 1: and what do we do with the high level stuff?

Speaker 2: The internationally agreed approach right now is deep geological repositories. Basically burying it deep underground in stable rock formations using multiple engineered and natural barriers to contain it for extremely long periods.

Speaker 1: Is recycling an option? The paper mentions that

Speaker 2: It does. You can potentially reprocess used fuel to extract leftover uranium and plutonium, which can be made into new fuel. It reduces the volume and long-term radioactivity of the final waste, but it’s complex, expensive, and raises concerns about nuclear proliferation, the risk of weapon materials being diverted so it’s not universally adopted for the waste components that can’t be recycled. They can be vitrified, turn into a stable glass form before disposal.

Speaker 1: What about SMR waste? Is it different

Speaker 2: that’s still being studied? Some SMR designs might produce less waste per unit of energy. Others potentially more depending on their specific fuel and how efficiently they burn it. It’s not as simple SMRs make less waste picture yet.

Speaker 1: Okay, so finally, how does the paper compare nuclear directly against the main renewables? Solar, wind, hydro.

Speaker 2: It contrasts nuclear stability and consistency. That base load power with the inherent variability of solar and wind, which depend on weather and time of day.

Speaker 1: Both low carbon in operation,

Speaker 2: though, both very low carbon during operation? Yes, but again, the paper touches on lifecycle emissions from manufacturing panels, turbines, et cetera. A big difference highlighted is land use. Nuclear power plants have a very small land footprint compared to the vast areas needed for solar or wind farms to generate the same amount of power.

Speaker 1: Lifespan difference too?

Speaker 2: Generally, yes. Nuclear plants are often licensed for 40, 60, sometimes even 80 years. Solar panels and wind turbines typically have lifespans closer to 20, 30 years,

Speaker 1: and the waste comparison again.

Speaker 2: Renewables generate large volumes of material waste at end of life panels, blades, batteries. Nuclear waste is much smaller volume, though radioactive. Its radioactivity decays over time. Whereas the material waste from renewables doesn’t just disappear.

Speaker 1: So reliability challenges and storage limitations for renewables still play a big role.

Speaker 2: They do. And the paper essentially suggests that the most robust, reliable, low carbon energy system likely needs a mix using both renewables and nuclear power working together.

Speaker 1: Okay, so wrapping this up, this really suggests nuclear energy is a serious contender for a carbon-free future. It brings that reliable, low emission power, and SMRs add an interesting new dimension,

Speaker 2: but it’s not without hurdles. The Waste Management Challenge is real Safety perceptions matter hugely, and the upfront costs are significant. These need careful, honest consideration.

Speaker 1: It really does sound like finding the right balance. Maybe combining nuclear strengths with the growing potential of renewables is where we’re headed.

Speaker 2: That seems to be the direction many analyses point towards. So hopefully this discussion has given you, our listener, a clear picture of nuclear’s potential role, some of the nuances, and maybe address some common questions.

Speaker 1: What parts of this still feel unclear or what other energy solutions should we be looking at? And maybe a final thought to leave you with, given how urgent the climate situation is and knowing renewables alone face challenges with storage and intermittency. Right now, could the risk of ignoring nuclear’s potential, assuming we implement strong safety and waste protocols, actually be. Bigger than the risks we perceive in embracing it.

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