It’s a common refrain among climate change down-players — those who accept its reality, but who argue that we can’t or shouldn’t do much about it — that, sure, first world Western countries could be doing a lot more to reduce their emissions, but it hardly matters when you’ve got countries like India and China pumping more and more pollution into the very same biosphere. The argument has been getting weaker in recent years, as even developing nations have started to sign on to meaningful climate action plans. Now, Chinese atomic energy experts have announced an ambitious plan to begin turning the country’s coal plant infrastructure into working nuclear power stations. The first working demonstration unit could begin real commercial operations as early as 2018.
The plan could turn the growing Asian nation into one of the world’s most aggressive actors on climate change — though just as important to China is nuclear’s ability to help deal with its growing problem with air pollution. It could also kickstart the global nuclear industry, which was flagging even before the Fukushima disaster of five years ago. China may be about to prove that newly advanced nuclear tech offers a way for some large industrialized nations to dramatically reduce their carbon footprint without bankrupting themselves, or simply betting that solar and wind power will progress fast enough to matter at all on the global utility scale.
Germany’s THTR-300 high temperature gas-cooled reactor.The news comes from this year’s High Temperature Reactor Conference, where Professor Zhang Zuoyi reportedly gave a talk on the subject, receiving a “sustained round of clapping,” complete with “a few hoots” from the gathered scientists. The reason for their enthusiasm should be obvious. Here, we could have a potential solution to the biggest practical problem with a large-scale pivot toward “Generation IV” nuclear designs with advance, passive safety systems: cost. Under the proposed plan, China can use re-use a huge proportion of the money it spent building coal plants, removing the furnaces and boilers from its super-critical coal plants and replacing them with the stripped-down hearts of high-temperature gas cooled nuclear reactors (HTGRs).
The coal stations targeted under this plan are numerous, but specific. Only super-critical steam plants are built to withstand the high operating temperatures HTGRs require. The early target stations should also be as close to population centers as possible — again, one of the main goals here is to reduce the health effects of coal plant air pollution, and you can’t accomplish that by reducing emissions in the middle of nowhere. So, if this plan is to actually go forward, it will need make a strong case for its own intrinsic safety.
A graphite-shelled nuclear pebble.
As a result, the project will focus on a form of nuclear plant called a pebble-bed reactor, in which the nuclear fuel is divided into little micro-fuel pellets that are then built up to baseball-sized spheres with successive layers of graphite and ceramic materials. The coatings on each fuel pellet act as the neutron moderator, doing the same job as the water that lies between the fuel rods in a classical thermal reactor, and the melting points of these coatings are all higher than any temperature the fuel pellets can create in this reactor.
Hundreds of these spheres become a rubble pile with space in between for gas to flow, in this in this case helium, and absorb heat before carrying it away. In some cases, this heated gas directly turns a turbine, but in this plan it will heat a duo of boilers to create steam, and turn the turbine more traditionally. The lack of the notoriously complex cooling systems of water reactors is one of the things that makes the Chine
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