The heat created by fission turns the water into steam, which spins a turbine to produce carbon-free electricity. All commercial nuclear reactors in the United States are light-water reactors.
This means they use normal water as both a coolant and neutron moderator. These reactors pump water into the reactor core under high pressure to prevent the water from boiling. The water in the core is heated by nuclear fission and then pumped into tubes inside a heat exchanger. Those tubes heat a separate water source to create steam. The steam then turns an electric generator to produce electricity.
BWRs heat water and produce steam directly inside the reactor vessel. Water is pumped up through the reactor core and heated by fission. Pipes then feed the steam directly to a turbine to produce electricity.
Government-led efforts to produce power from fusion have been going on around the world for 50 years. But the availability of equipment and technology has seen an increasing number of amateurs enter the fray. Some experts are sceptical that all these people are producing fusion reactions, but when he demonstrates his device, Mr Suppes says a bubble meter placed next to the reactor indicates that a fast neutron, a by-product of fusion, has been produced.
Mr Suppes sees his work in nuclear fusion as more than just a hobby, and he intends to try to build one of the world's first break-even reactors - a facility producing as much energy as it uses to operate. Mr Suppes is hoping to build a break-even reactor from plans created by the late Robert Bussard, a nuclear physicist who drew up plans for a fusion reactor that could convert hydrogen and boron into electricity. Work on a scaled up version of a Bussard reactor, funded by the US Navy, has already been taking place in California.
But Mr Suppes believes he will be able to raise the millions of dollars it takes to build a Bussard reactor because he feels someone with enough money "will feel they cannot pass up the opportunity" to find out if it will work. Iter said it would be wrong to dismiss out of hand the notion that an amateur could make a difference.
For Mr Suppes, convincing the experts is one thing. Convincing the locals is another problem entirely. But others had a more positive outlook on Mr Suppes' reactor. If a guy can make an invention like that, it should definitely be spread around so we don't need to depend on oil," Brooklynite Chris Stephens told the BBC.
Is fusion power really viable? Man-made star to unlock cosmic secrets. N Korea 'nuclear fusion success'. Such licence extensions at about the year mark justify significant capital expenditure needed for the replacement of worn equipment and outdated control systems. In France, there are rolling ten-year reviews of reactors. There are plans to take reactor lifetimes out to 60 years, involving substantial expenditure. The Russian government is extending the operating lifetimes of most of the country's reactors from their original 30 years, for 15 years, or for 30 years in the case of the newer VVER units, with significant upgrades.
The technical and economic feasibility of replacing major reactor components, such as steam generators in PWRs, and pressure tubes in CANDU heavy water reactors, has been demonstrated. The possibility of component replacement and licence renewals extending the lifetimes of existing plants is very attractive to utilities, especially in view of the public acceptance difficulties involved in constructing replacement nuclear capacity.
On the other hand, economic, regulatory and political considerations have led to the premature closure of some power reactors, particularly in the USA, where reactor numbers have fallen from a high of to 94, as well as in parts of Europe and likely in Japan. It should not be assumed that a reactor will close when its existing licence is due to expire, since operating licence extension is now common.
However, new units coming online have more or less been balanced by the retirement of old units in recent years. Over , reactors were retired as started operation. There are no firm projections for retirements over the next two decades, but the World Nuclear Association's edition of The Nuclear Fuel Report has reactors closing by in its reference scenario, using conservative assumptions about licence renewal, and coming online.
Plans For New Reactors Worldwide Updated November Nuclear power capacity worldwide is increasing steadily, with about 50 reactors under construction. Most reactors on order or planned are in the Asian region, though there are major plans for new units in Russia.
0コメント