And many reactors are able to modulate their output, either by absorbing neutrons to slow the chain reaction, or by letting steam bypass the turbines.
https://www.energy.gov/ne/articles/3-ways-nuclear-more-flexi...
For condos and apartment buildings by far the most common method of heating is district heating (teleheating) [1], and historically this has been very carbon intensive, even though cogeneration of both heat and electricity in one plant is quite efficient (efficiency > 80%; most Finnish thermal power plants are cogen). Fossil fuels and peat are being replaced with more sustainable (mostly wood-based) fuels, but attaining the emission goals requires burning less fuel, period, which means technologies like geothermal boreholes and large-scale heatpump facilities.
SMR nuclear reactors, if they ever become mainstream, would be an excellent source of clean heat and electricity for cities. Current nuclear power plants are located (by design) too far from cities for it to be economical to pipe their waste heat to where it's needed.
Its operating cost will necessarily be quite a bit more than solar, but it works in the Arctic winter, 24x7, and provides cogen heat.
It might end up cheaper to ship in ammonia synthesized from solar in the tropics. Most likely it will be a combination of several: normally, delivery by transmission line because cheapest, but with geothermal held ready for strategic backup, and stockpiled ammonia for load peaks.
Shipping will get cheaper as fuel does, but is already astonishingly cheap.
I’m not aware of any significant and serious efforts to replace ships with a green fuel, and they comprise a huge percentage of our emissions.
The west-African coastal Sahara, coastal Peru/Bolivia, Baja California, Arabia/Sudan/Eritrea, Yemen/Oman/Pakistan, Socotra, and north-western Australia all look like good places to site solar-driven ammonia synthesis. I don't doubt that less geographically-favored sites will dominate instead.
Some 42 million megawatts of energy reach the surface continually and are radiated into space as the earth cools from its initial molten state more than 4 billion years ago. No feasible amount of geothermal development could make even a small dent in this process. Furthermore, the earth’s heat budget is continually replenished by the radioactive decay of naturally occurring elements, and almost all of the energy associated with each decay event is converted to heat. Plus, the heat content of the geothermal reservoir rocks is continually replenished by conduction of heat from the earth’s deeper interior.
So a single nuclear power plant would be roughly equivalent to 0.002% of earths geothermal energy radiation. It doesn't sound like much, but for something as crucial as the earth's magnetic field, I wouldn't want to reduce it one bit.
I guess if the heat is radiated into space anyways and we simply capture that it doesn't speed up the core's energy loss, but if we start digging into the core and allowing energy to escape faster, we would effectively speed it up, right?
The radius of the Earth is 4000 miles. A 10-mile hole is thus 1/400 of the way to the center. You may as well worry that scratching the skin of an apple might damage the seeds.
Look at a graph of the temperature of the Earth as a function of depth. The temperature jumps tremendously below the crust, and is much more stable per depth below. The crust is the insulation of the Earth - and damaging that crust might affect the mantle is ways we cannot yet imagine.
The answer remains "we don't know".
The argument "it's big, we can't affect it" has been proven wrong in the case of the atmosphere, and again in the case of the ocean. It is no longer a sound argument.
Eruptions in Siberia, and later in India, not long ago geologically, released more heat in a (geologically) short time than we could use up in a million years, with no effect on the Earth's magnetic field.
I don't think we're even digging through the crust - there'd still be the mantle (~100x thicker) before we got to the core.
In numbers, I believe the deepest borehole is ~12km deep... and the Earth has a radius of >6000km. We're barely scratching the surface.
Since the layers are directly connected, it doesn't sound like to me that you'd have to dig into the very core for that to happen.
Of course at the current state of affairs the effects are miniscule, but it doesn't sound like a very good investment as something to potentially scale up in the future to where it will actually matter.
If it turns out to be a problem, how hard would it be to insert fuel back into the earth's core to sustain the magnetic field?
In another century, if we don't blast ourselves back to the stone age first (increasingly likely), energy from hydrogen-boron fusion will dominate wherever solar is impractical, and the geothermal wells will become too expensive to continue operating. So, either way, the whole process is an imperceptible blip.
Blasting our way back to the stone age will succeed in chopping off CO2 output suddenly, though. The climate could then return to normal in only a century or three, if the sudden change did not instead trigger an ice age or something.
You should worry instead about the effects of excreted pharmaceuticals and neo-nicotinoid pesticides on wildlife, excess fertilizer runoff on coastal ecosystems, and ocean acidification from CO2 dissolving to produce carbonic acid, making sea life unable to fix calcium for shells, destroying the underpinnings of the food chain and the whole ocean ecosystem. Oh, and global climate disruption.
We have no need to borrow imaginary trouble, we are making plenty of actually real trouble already.
I don't believe that waste heat is plenty. Here, in Romania, we use the waste heat from the nuclear power plant as district heating but that is enough for a small town near it.
You can have tiny heat pumps in every home that share a district-wide pipe as a heat source, you can use giant/deep heat pumps to supply the district-wide pipe and you can do both at the same time. And heat pumps can also be used to cool things, returning heat into the system and allowing for big solar gains in windows, since the heat generated can be re-used when it's more than needed rather than wasted.
In any case, the cost/kWh from nuclear is computed assuming it's running flat out (except for refueling outages). Reduce that generation and the levelized cost increases. It's already very much higher than renewables; curtailing nuclear output would make that discrepancy worse.
Note that even some of the OPERATING costs of a nuclear plant are fixed. You still need about as many staff to run the plant even if you cycle it up and down.
The renewables will be wind and PV. Biomass uses too much land area, and would likely be reserved for specialty markets like chemical feedstocks and perhaps aviation fuel.
?? What renewable isnt given that?
Nuclear works when you want it to. Solar and wind work when they want to. That's a very big difference when you're producing the electricity people rely on to live their daily lives.
Hydrogen can be much cheaper for (say) the last 10%, because (1) hydrogen has very low capital cost per unit of storage capacity, and (2) the efficiency hit of going through hydrogen vs. batteries is less important when it's just 10% of the total.
Think of batteries and hydrogen as analogous to cache memory and main memory in a computer. They have different performance and economic characteristics and compensate for each others weak points.
To see this in operation, go to https://model.energy/ and try turning hydrogen off and on in the settings. If you simulate for Germany, for example, turning off hydrogen can double the cost of achieving a certain level of constant grid power. Hydrogen can be particularly valuable for places with large seasonal variation or lots of wind (which has a long timescale component in how it varies.)
I will add that China is already selling electrolysers for < $300/kW, less than half that simulation's 2030 cost assumption.
Basically all hydrogen comes from fossil fuels. It's just natural gas with extra steps.
When describing hydrogen for energy storage in a 100% renewable grid, the hydrogen would be produced by electrolysis using renewable energy.
I once compared a proposed pumped hydro system in Arizona near Phoenix vs. the water evaporated by the Palos Verde nuclear generating station. Per unit of levelized power output, the pumped hydro system used at least an order of magnitude less water than the nuclear plant.
If the panels don't mind settling on the banks, or if they are far enough offshore not to, that will not be a problem. It is already common to float panels on regular hydroelectric generation reservoirs, so the event is anyway familiar to operators.
If the floats are bottom-heavy and attached to cables spanning the reservoir, the water dropping out from under just leaves them suspended. You need cable attachments, anyway, to extract power and maintain spacing.
Nuclear provides a path for decarbonization. Solar and wind do not, until a massive breakthrough in energy storage is invented. And nobody knows when that will happen, or if it will happen.
As for storage, one way to "store" energy is hydrogen, which we can then burn as needed. We can probably get the efficiency of that to 70% (for hydrogen-burning larger-scale power plants).
Pumped-storage hydroelectricity is another existing option, with an efficiency of about 70-80%.
It's also OK to have some carbon emissions if you can manage to have other measures neutralizing that. We can e.g. use renewable biofuels (e.g. wood, biomass from algae or crops) which "use" a lot of carbon while growing to remove a lot of the emissions the power plants produce, and can with filter technology remove the rest to a degree where we'd still be neutral overall.
As I see it, we already got all the basic building blocks, and now it's a matter of optimizing them further and further, and more importantly figuring out the development and deployment (including financing, investment incentives, etc) and logistics (building the additional power lines required is a massive, politically-charged, often NIMBY-kind challenge here in Germany, and from what I hear in a lot of other places including the US too).
The deployment and logistics is a general problem of electrification, even with nuclear. People want to plug in their EVs near where they live, and want heat in their homes, so you either need additional power lines or (smaller scale) power plants close to people and industry, either way.
Decarbonization is maaaybe 1/4 of the way there, but folks seem to like to spin it as 90%.
You're absolutely right that we will need to spend a lot of money and time if you seriously want to achieve to become globally carbon-neutral. However, going nuclear wouldn't be necessarily cheaper or quicker, either.
Which makes a war of conquest or destruction by countries not doing so much easier to win.
Edit: Also, with interest rates likely to go up due to inflation/central bank action, that CapEx may soon be impossible to bear without some equivalent to a wartime economy anyway. A lot of the renewables have been helped by essentially free money.
You can see that in a lot of consumer products already, when the EU e.g. started to mandate to put energy consumption ratings on electric appliances, and the market then swiftly went to improve the power consumption in most cases. I grew up with regular light bulbs, but now I and everybody I know largely uses LED light bulbs, again driven by consumer demand and heavily nudged by political policy in the EU. And I either save money now or at least break even thanks to my electric bill being less, and LED lights usually lasting so long they are over time cheaper than the old regular bulbs.
I wouldn't dare try to predict how these things would actually shake out eventually.
Most of the easy improvements have already been done. with the possible exception of insulating more (far harder than changing out electric bulbs or when new appliances get bought or computers age out replacing them with higher efficiency versions). Normal ICE cars and trucks have also hit diminishing returns efficiency wise.
Usually not so easy though as it may seem, especially in concrete, stone, or other masonry buildings which are very common in Europe.
What I’m referring to is far coarser grained, and on the production side.
Fossil fuels are very, very energy dense, and that energy is released/used through completely different mechanisms than electrical energy. So for heat, even if switching to heat pumps which are over unity devices (1 Input unit of energy can move almost 3x units of heat), the amount of energy required to do so for countries which need a lot of heat is astronomical. I did some back of the envelope math for Germany in another thread, and even being very conservative we’re talking 7x the total energy requirements of their current entire grid to replace natural gas for them.
So it’s more than just buying a heat pump and installing it, it’s a massive undertaking involving the equivalent of $120-$600k+ of capex to accomplish. That is for every many woman and child when you add it all up. One would hope they could be more efficient, but those prices already involve a huge economy of scale.
If the EU forms an army and has mandated no fossil fuels, they would need to spend a massive amount more capex to build that army than if they did not right now, let alone keep it energized. That takes time, resources from other things, and exposes them to unique supply chain challenges too.
If they want to just switch their economy off fossil fuels, right now that will likely take a 5-10 years even on a wartime footing. It takes time to build factories, source materials, R&D complex things. Many of these will depend on countries they may not want to depend on (such as chips from China or raw materials currently sourced from Russia). And that is a massive amount of money, on top of likely weapons manufacturing, etc.
If they wanted to do it in 2 years, I’m not sure it’s possible right now.
These are geographically dependent. You can't build the where you need them.
> As for storage, one way to "store" energy is hydrogen, which we can then burn as needed. We can probably get the efficiency of that to 70% (for hydrogen-burning larger-scale power plants).
Large scale electrolysis remains unproven. This goes in the "scientific breakthrough required" bucket.
> Pumped-storage hydroelectricity is another existing option, with an efficiency of about 70-80%
Also geographically dependent. You basically need an alpine lake handy to build pumped storage.
Carbon sequestration at anything close to relevant scales also has never been done.
> The deployment and logistics is a general problem of electrification, even with nuclear. People want to plug in their EVs near where they live, and want heat in their homes, so you either need additional power lines or (smaller scale) power plants close to people and industry, either way.
No, this isn't a problem with nuclear. Most energy demand is in cities. And since nuclear plants are not geographically dependent, you can build them near places with lots of energy demand. As opposed to renewables which might need to be built very far away in places with large solar or wind potential.
Large-scale electrolysis is not unproven. E.g. Air Liquide operates a 20MW plant producing 3000t/annum near Quebec already[0]. Other projects in development aim for 200MW facilities. Granted, that isn't yet massive scale, just about 99,000 MWh/annum of usable energy (about 33kWh/kg for hydrogen), and the smallest US nuclear plant is theoretically capable of 5,098,320 Mwh/annum or around 50 times more. But large scale enough to act as a proof of concept in my opinion.
Pumped storage is a bit geo-dependent, but you do not need an alpine lake, you need an empty space somewhat higher up where you can pump some water, preferably without loosing too much water due to evaporation and other factors, and some water, preferably fresh water to avoid corrosion as much as possible, maybe desalinated. But if need be salt water and an artificial hill will do.
As for the deployment and logistics of nuclear, it is certainly a problem. Our current grids, independent from the form of electricity generation, are usually not designed to handle the growing demand that electrification probably will create. You can see what happens when the demand somewhat suddenly rises (and the EV introduction is still somewhat "sudden" in the time scales grid operators and infrastructure planners usually consider) e.g. in Kazakhstan when the Chinese bitcoin miners moved there[1]. Furthermore, planning, building and testing new nuclear plants is a massive capital expenditure even without technology research, as well as a political hot topic in a lot of places (and even in nuclear-friendly regions I'd bet that NIMBYs would form real quick once a location for a new plant gets discussed).
Last thing I read by the way is that the EU gets about 20% of the Uranium it uses to fuel existing nuclear plants from Russia (at least until now), with another ~20% coming from Kazakhstan[2], which is somewhat closely allied to (and for sure scared of) Russia. Another ~20% come from Niger, a country not exactly renowned for being a politically stable and human-rights respecting nation. Maybe the EU can source elsewhere, even if the demand increases as potentially more nuclear within the EU goes online, but it surely has a rather problematic political dimension attached aside from general nuclear politics such a nuclear proliferation. And it's not just the EU which needs to switch to electrification, either. Where will Africa or Latin America or Asia get their nuclear tech and nuclear fuel?
Nuclear, like oil, creates international political dependencies in a lot of places, while most renewables would not necessarily do the same.
[0] https://www.spglobal.com/commodity-insights/en/market-insigh...
[1] https://www.bloomberg.com/news/articles/2022-01-25/kazakhsta...
[2] https://ec.europa.eu/eurostat/statistics-explained/index.php...
The hydrolysis example you provided is tiny relative to the requirements of grid scale storage. To put this in perspective, the US alone uses 500 GWh of electricity every hour. And this will increase as electrification progresses, electricity only accounts for about a third of total energy production. Producing grid scale hydrolysis remains unproven.
The same reliance on a globalized economy still exist with intermittent sources. The copper used in wind turbine generators probably comes from Chile, for instance.
That will, of course, still need to be developed to production. But it is a (large) incremental process improvement, not a whole different technology.
First you said hydrolysis was not practical at all. Today you say 200 MW facilities are not big enough. What will you say tomorrow? Why not admit it now?
Throughout this whole thread you've been pointing to proposals and plans as though simply having plans is a demonstration of viability. Unless people are actively implementing the solutions you're proposing, then those solutions aren't proven to work. There's a massive difference between pointing to an entrepreneur that promises this special drill will be able to build geothermal plants anywhere, and actually building geothermal plants in the middle of Germany. There's a massive difference between plans that promise to store X amount of hydrogen, and actually building and running said storage plants. Electrolysis has been known for at
As far as I'm concerned, both hydrolysis and this geothermal-anywhere approach fall into the bucket of "scientific breakthroughs". Could they be viable if they pan out? Sure. But it's highly unwise to bet the future of civilization on something that might work out, as opposed to something that's been operating at scale for most of a century.
1. https://www.newscientist.com/article/mg21628955-900-laser-dr...
60 years, by the way, pushes the boundary of "most of a century".
Let's actually put this in perspective: Global electricity consumption is about 60 TWh daily, which works out to about 2.5 TWh per hour or 40 GWh per minute. Plans to run a wind and solar grid predict a 12 hour storage requirement to generate 80% of our energy from wind and solar [1], and weeks of storage for a 100% wind and solar grid. And remember, this is on top of the cost of actually generating all that energy in the first place. If people want to prove that these storage mechanisms are viable, then how about they build one minute's worth of storage. If we don't even have one minute's worth of storage provisioned, then I see zero reason to be confident in the ability to build hours, days, or weeks of storage.
By comparison, we'd need to build 9 nuclear plants for each one that presently exist to generate all of our electricity from nuclear. Any only 8 if we eliminate everything but nuclear and hydro. Also, It's 68 years since the first nuclear electrical plant and 80 years since the first fission reactor.
1. https://pv-magazine-usa.com/2018/03/01/12-hours-energy-stora...
Pumped hydro has always worked at scale.
You keep repeating that storage is not built out. We know. Before it can have been built out, it will need building out. But nukes are also not built out. Which can get done faster?
You just really wish storage tech was harder than it is because you need that for nukes not to look like the obviously bad investment they have proven, by "most of a century" of experience, to be.
By comparison, we need 6 to 7 orders of magnitude increase in our existing hydro and battery storage capacity to decarbonize through renewables. And an infinity order of magnitude increase in electrolysis storage, because we don't have any such storage at all. It's not that they haven't been built out. They haven't been built, full stop.
I don't need to make storage tech look any worse than it is. How much electrolysis storage capacity do we have, worldwide? Zero. I think you're the one engaging in wishful thinking, treating these totally unproven systems as certain when nobody has ever operated a grid storage electrolysis facility.
If someone told you they have plans for a supersonic passenger jet that will be even cheaper than normal airliners, would you believe them? If they actually had working planes, and they were actually able to build and operate a batch of a few dozen planes more cheaply than typical airlines then yes. But if they only had one plane, and little operational experience I wouldn't. And if all they had were plans on paper, I certainly would not - this is the stage that storage mechanisms other than hydro and batteries are in.
Pretending that "breakthroughs" will be needed to field storage must be your last hope, but building out storage is just construction. You will continue to be disappointed.
Come back to me when electrolysis storage systems are actually built, and we can examine the actual costs of storage the same way we examine the costs of nuclear: by looking at the bill after the plant has been built. If you really are so confident in their efficacy, then this should be no problem.
Today's thermal reactors, if they provided the entire 18 TW of primary energy demand, would consume in excess of 1 million tonnes of natural uranium per year. This would consume known uranium resources in less than a decade.
So, either seawater uranium would be needed (which would have to be scaled up by something like 11 orders of magnitude from what has been demonstrated) or breeder reactors would be needed (also not a proven technology, and likely more expensive than thermal burner reactors.)
The real figure [1] is 60,000 years worth of uranium with our current nuclear energy production, which is about 10% of our electrical demand. So 6,000 years for a 100% nuclear grid. Electricity production is about 25% of total energy demand, so call it 1,500 years for all energy converted to nuclear.
Furthermore, moving nuclear seawater extraction - even at it's present costs, without economies of scale - would not significantly impact nuclear's costs [2]:
> Fortunately, the cost of uranium is a small percentage of the cost of nuclear fuel, which is itself a small percentage of the cost of nuclear power. Over the last twenty years, uranium spot prices have varied between $10 and $120/lb of U3O8, mainly from changes in the availability of weapons-grade uranium to blend down to make reactor fuel.
> So as the cost of extracting U from seawater falls to below $100/lb, it will become a commercially viable alternative to mining new uranium ore. But even at $200/lb of U3O8, it doesn’t add more than a small fraction of a cent per kWh to the cost of nuclear power.
1. https://www.scientificamerican.com/article/how-long-will-glo...
2. https://www.forbes.com/sites/jamesconca/2016/07/01/uranium-s...
But deep subterranean cave and sub-ocean tanks for pumped hydro will be a thing. These make pumped hydro storage practical in radically more places than usually imagined. Combined with hill reservoirs, they multiply the storage capacity per unit mass of water.
A hilltop reservoir is, incidentally, an excellent place to site a solar array, which is cooled and more efficient by the water under it, and in turn radically reduces evaporative loss and biofouling in the reservoir.
We were originally planning to ditch domestic peat as fuel, in favor of Russian biofuel, but that's off the table now, and peat will probably be used extensively for a few years until alternatives are in place.
Energy independence is what we aim for at the moment. Carbon neutral is still something we aim for in the long run, but not being relianton Russian energy is the primary goal for the next few years.