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Small, Modular Nuclear Reactors — the Future of Energy?
cylonlover writes "This year is a historic one for nuclear power, with the first reactors winning U.S. government approval for construction since 1978. Some have seen the green lighting of two Westinghouse AP1000 reactors to be built in Georgia as the start of a revival of nuclear power in the West, but this may be a false dawn because of the problems besetting conventional reactors. It may be that when a new boom in nuclear power comes, it won't be led by giant gigawatt installations, but by batteries of small modular reactors (SMRs) with very different principles from those of previous generations. However, while it's a technology of great diversity and potential, many obstacles stand in its path. This article takes an in-depth look at the many forms of SMRs, their advantages, and the challenges they must overcome."
Distributed power is how our grid should be set up. Also, being self-contained, these would allow us to put them closer to the actual users and cut transmission losses and costs. Why the hell aren't we doing it yet?
-SaNo
There are no economically viable nuclear plants without heavy taxpayer subsidies.
The original post implies that nuclear plants have been turned down for decades and now suddenly they aren't. This is bullshit.
Corporations are lining up for the gravy train of taxpayer dollars provided by the Cheney energy policy of 2005. Per-kilowatt subsidies, construction subsidies, reauthorization and extension of the Price-Anderson Act (which makes taxpayers liable for disasters), all negotiated in secret because taxpayers don't want their money spent that way.
Nuclear power is no different than TARP. It's corrupt politicians giving away taxpayer money to their rich cronies. People don't want it, don't need it, and it's not competitive with any other source of power economically.
Use less energy and use it more efficiently.
Which unluckily is not what energy producers want.
Sent as ripples into the electromagnetic field. No single photon has been harmed in the process.
The good old days when we used to plow our fields with pointy sticks.
Too many little nukes around to regulate.
One of the selling point of electric cars is that they concentrate their pollution at a few large point sources. Sure, today they belch out coal byproducts. But as technology advances, we can monitor and retrofit a few large plants more quickly than having to hunt down the owner of every old beater car. These modular nukes are the logical equivalent of a fleet of cars. Eventually, they'll descend into beaterhood.
Have gnu, will travel.
So you know, the plow of the 18th century was not just a pointy stick, it was actually pretty good at its job, which was why it was used so widely. The biggest difference between that plow and the ones used today is that we now have a tractor in front pulling it instead of oxen or horses.
The farmers of yore might not have had the same understanding of agriculture as us modern folk, but they weren't stupid, and they would have abandoned tools that didn't help them grow more crop.
I am officially gone from
I think you underestimate the size of the storage problem. The main problem with wind and solar are seasonal variations - even though we currently can't even manage to cope with the short-term ones. You will need at least 2 months of storage to deal with the time around winter when demand is largest and supply is smallest. (That's without some extra reserves to deal with unforeseen events.) For Germany that's 100TWh. For short-term variations about 2 days or so could be sufficient, about 3-4 TWh. Pumped storage in Germany has a capacity of about 0.04 TWh. (Of course, 40GWh sound a lot more impressive, but really isn't.)
The elephant in the room is of course that the majority of energy use is not electricity, but oil and gas used for transport, process heat and heating, only some of those can be significantly reduced through the use of electricity. (Process heat, for example, is too hot for effective use of heat pumps. 1kWh of heat takes 1kWh of electricity there. For space heaters, you may get 4kWh of heat for 1kWh of electricity.) About 30% of the primary energy (30% of about 15000 PJ) in Germany is converted into electricity - with some 40% efficiency. Thus, current electricity generation (600TWh per year, or 2200PJ or 70 GW) is just a small fraction of total energy use (15000PJ per year or 480 GW). Electricty supply would need to at least double, more likely triple, to replace oil and gas. Which is a pretty optimistic assessment - you're doing with perhaps 5000PJ per year (160GW) of electricity what used to take 15000PJ (480GW) of energy.
As for storage? Well, batteries are not enough for long term storage, but short term, they are a very efficient and very expensive alternative. The bulk will inevitably need to be some derivative of hydrogen, probably methane (for much easier storage). The problem with that is that efficiency is quite bad - some 33% round-trip. (Not accounting for energy used in liquification or pressurization for storage. But 33% is a reasonable estimate if you take probable technological improvements into account. This is limited by turbine efficiency, which is actually better than fuel cells for large, multiple stage, plants.) So, you will need to roughly double the figure of electricity generated by wind or solar, if you want to know what you will get out. So, you're now talking about generating on the order of 8000PJ per year (250GW) with wind and solar. (Biofuel and hydro is not scalable, tidal quickly gets huge, but so does wind and solar at this kind of scale.)
On average, Germany is now producing 2.75 GW of solar (with 27GW installed capacity) and 4.5GW of wind power (also 27GW installed capacity - but without current downtimes due to electricity net congestion, it could be over 6GW). So, you would need roughly a 25 fold increase wind and solar, as the only scalable renewables, provide renewable energy to Germany. And that is huge all by itself.
You're describing previous generations of reactors. The new ones are more like a giant battery. They are sealed, self contained, and walk-away safe.
Walk Away safe is a pretty big claim for something that has never actually been built yet. (And no, Navy shipboard reactors don't count. Operation of those reactors is top secret, and they are way too small.)
At some level, the concept of "walk away safe" is just another example of The Arrogance of Engineers. There are just too many things assumed.
The real problem with this design is that it might actually be built in reasonably large numbers, installed in places that are less well planned, operated by your average mid-sized power company, guarded by Mall Cops, maintained by low-bidders, and inspected by bribe takers.
In short, this type of reactor has the ability to become far too ubiquitous before any of the inevitable problems are discovered after 10 years of operation.
One could say that they may be too successful, too quickly.
Sig Battery depleted. Reverting to safe mode.