Nuclear Video Bar


Friday, 22 July 2011

Buletin Nuclear Energy~

Should Malaysia go nuclear to meet its future energy demands? That question has been the focus of heated political debate in Malaysia for the past eight years. Mahathir Mohamad, who served as prime minister from 1981 to 2003, was firmly committed to a non-nuclear Malaysia. But since his departure, his successors have made some moves toward nuclear energy production. In December 2010, for example, Peter Chin, the country's energy minister, announced plans to build two 1,000-megawatt nuclear power plants by 2022. A month later, Prime Minister Najib Razak announced the establishment of the Malaysian Nuclear Power Corporation, which will lead the planning process.
The Fukushima nuclear accident, however, has raised new doubts about whether Malaysia is ready for nuclear power. Malaysian experts disagree over the need for nuclear power plants, and their potential impact on public safety and the environment. There is little doubt that Malaysia must develop new energy sources to meet its future energy demands without relying on costly foreign imports. But these demands can be met with renewable energy instead.
A history of successful energy policy. In any debate over Malaysian energy policies, three important documents are always used as points of reference. The first was Malaysia's 1979 National Energy Policy, the objective of which was to ensure an adequate, secure, and cost-effective supply of energy -- as well as to promote energy efficiency while discouraging wasteful and unproductive patterns of energy consumption. The second key document was the 1981 four-fuel diversification policy, which was formulated to reduce over-dependence on a single fuel source by developing four types of energy: hydropower, oil, natural gas, and coal. Finally, the third reference point was the five-fuel diversification policy introduced in 2000, which included renewable energy (except hydropower) as a fifth energy source.
These three policies have worked well to fulfill the energy demands of the country, and have received widespread support. But now that nuclear power is being considered as Malaysia's sixth fuel, there is no longer general agreement on energy policy. Three main groups have emerged: one that strongly favors the development of nuclear energy, another that supports nuclear energy but is concerned about safety and environmental effects, and a third group that rejects any moves toward nuclear power in Malaysia.
The need for nuclear. 
Proponents of nuclear power point to the current energy situation in Malaysia as evidence that new energy sources must be developed. Government officials believe that Malaysia's current energy sources will not be sustainable beyond 2020, and that the depletion of the nation's fossil-fuel resources is a threat to national security.
Analysts predict that escalating global oil prices will force Malaysia to become a net oil importer in the years to come. Malaysia uses oil mainly in the transportation sector, and relies on natural gas and coal (along with hydropower) to generate electricity. However, government officials have expressed concern that the cost of coal and gas is likely to soar in the coming decades, as supply fails to keep up with demand. Malaysia's coal imports, which held steady for many years, have grown rapidly in the past two years. Natural gas is currently the largest energy source for the country, but national gas fields may be depleted by 2027, which would leave the country unable to meet petrochemical industry demand and commitments for exports of liquefied natural gas.
Because of these gathering storms, there is no doubt that Malaysia urgently needs new sources of energy to assuage its future energy demands, and nuclear energy seems a very attractive alternative -- particularly since the neighboring countries of Vietnam and Thailand have already announced plans to bring their first nuclear plants online by 2020, and Indonesia intends to construct a plant on Java Island by 2015. Nevertheless, for Malaysia, the prudent management of current energy resources -- to ensure that they are sustainable over the long term -- deserves serious consideration as an alternative to nuclear energy.
The dangers of a nuclear Malaysia. 
Even before the Fukushima accident, anti-nuclear lobbyists in Malaysia raised concerns about the potential for an accident like the 1986 Chernobyl disaster. Going nuclear is highly risky for any country, and would be especially problematic for Malaysia -- a nation less capable of coping with a nuclear accident than countries such as Japan and Russia.
The most formidable challenge is how to get rid of nuclear waste that cannot be recycled and therefore would need to be stockpiled. To date, nobody has come up with a method for safely disposing of highly radioactive wastes from nuclear plants.
The radiation cleanup under way in Bukit Merah, in north-central Malaysia, is a cautionary tale. A rare earth refinery there, which contaminated the surrounding area with radioactivity, is blamed for a rash of birth defects, miscarriages, and leukemia cases. Mitsubishi Chemical closed the refinery in 1992 and has buried some radioactive materials inside a nearby hill. This summer the company plans to entomb more than 80,000 steel barrels of radioactive waste in the hill.
Another challenge is how to protect a nuclear power plant from earthquakes, which can damage reactor containment structures and expose the nation to the risk of radiation leaks. Areas around Janda Baik and Bentong, towns in the Malaysian state of Pahang, have experienced minor quakes twice in the past few years. Volcanic eruptions in nearby Indonesia have also shaken some areas, although Malaysia is not located in the Pacific "ring of fire" that is home to most of the world's volcanoes. Malaysia cannot afford to risk building a nuclear plant in an area that could be vulnerable to a volcano or earthquake; the consequences would be too devastating.
A better choice. 
Despite all the criticisms and concerns expressed by the general public as well as by activist groups, the Malaysian government has not been able to provide any assurances that nuclear power will be safe and environmentally friendly. If government officials persist in going nuclear without providing satisfactory assurances, they will likely face unwelcome political repercussions.
Public opposition has intensified since the earthquake and tsunami in Fukushima. Japan is a much more technologically advanced nation than Malaysia, yet it has struggled to cope with the ongoing disaster. Had a similar accident happened in a less developed nation, the crisis may have been even worse.
Malaysia's neighbors have decided to forge ahead with nuclear power. But Malaysian anti-nuclear lobbyists believe that, unlike neighboring countries, Malaysia has plenty of energy reserves -- perhaps as much as a 40-percent margin over consumption, twice the government's estimate -- and will not face any power shortages in the near future. That makes construction of a nuclear reactor completely unnecessary, these lobbyists argue.
Malaysia's power usage is currently about 14,000 megawatts out of a total generating capacity of 23,000 megawatts.The Bakun Dam, nearing completion in the Malaysian state of Sarawak, will add another 2,400 megawatts of capacity. Located on the Balui River, the Bakun Dam will be the tallest concrete-faced rock-fill dam in the world, and the largest Asian dam of any kind outside of China. The plan is to send the electricity through cables crossing the South China Sea to the Malaysian Peninsula, where there is more demand than in Malaysian Borneo. Several other giant dams are also planned for the jungles of Borneo, together adding another 4,600 additional megawatts of generating capacity to the Malaysian portfolio.
Malaysia is also exploring other renewable energy options PDF including biomass, biogas, mini-hydropower systems, solar photovoltaics, and generating electricity from municipal waste. The total generating potential for these renewable resources is more than 9,000 megawatts.
The problem with nuclear energy, compared with all other sources of electricity, is that when things do go wrong, the consequences are far, far worse. Fortunately, Malaysia has safer choices available. By focusing on improvements in efficiency -- and investing in renewable energy sources such as in solar, wind, and hydropower -- Malaysia can continue to meet its growing energy demands well into the future.

    Monday, 18 July 2011

    How Nuclear Power Work


    Uranium deposits are found in rocks around the world. The two largest producers of uranium are Canada and Australia. Uranium is recovered either by mining hard rock or by in situ leaching (ISL), where dissolved from the orebody in situ, the solution then being pumped back to the surface. If uranium is mined the rock is crushed and then leached to dissolve out the uranium, which is then precipitated out of solution as the uranium oxide U3O8, sometimes known as 'yellowcake'

    Conversion, Enrichment and Fuel Fabrication

    Most reactors use fuel enriched in the U-235 isotope. The solid uranium oxide from the mine is converted into the gas UF6, which is then enriched in the U-235 isotope by one of two physical methods of enrichment. Diffusion enrichment, works by exploiting the different speeds at which U-235 and U-238 pass through a membrane. Centrifuge enrichment, works by passing the gas through spinning cylinders, the centrifugal force moving the heavier U-238 to the outside of the cylinder, leaving a higher concentration of U-235 on the inside.

    Uranium dioxide pellets are produced from the enriched UF6 gas. The pellets are then encased in long metal tubes, usually made of zirconium alloy (zircalloy) or stainless steel, to form fuel rods. The rods are then sealed and assembled in clusters to form fuel assemblies for use in the core of the nuclear reactor.

    Electricity Generation

    Nuclear reactors produce electricity by heating water to make steam. The steam is then used to drive turbines that generate electricity. In this sense  nuclear power  plants are similar to other thermal power stations, where the heat from burning coal or gas is used to produce stream. A key difference of nuclear reactors is that they don't emit carbon dioxide. A nuclear chain reaction is so-called because when a U-235 atom splits (or fissions) in the reactor's core the neutrons released cause other uranium atoms to also undergo fission. A moderator slows down the neutrons to achieve this. The nuclear reactor uses control rods to ensure that this chain reaction occurs at a controlled rate.

    Used Fuel Management

    Used fuel from a nuclear reactor is first stored to allow most of the radiaoactivity to decay. Then it can either be reprocessed to recover the reusable portion, or it may be disposed of directly as waste. In reprocessing, the used f fuel is dissolved and the uranium and plutonium in the used fuel are separated from the waste fission products. Plutonium can then be combined uranium to make Mixed Oxide Fuel (MOX), which can be used in many modern reactors. Reprocessed uranium can be used in new uranium oxide fuel.
    No underground facilities have yet been built for used fuel, although several are planned.

    More on used fuel management 

    Waste Management

    Nuclear wastes range from low level wastes, which contain barely radioactive materials through to high level wastes such as used nuclear fuel that is not destined for reprocessing. Low level waste facilities are already in operation, taking wastes not only from the power generation sector, but also those from nuclear medicine. High level waste is currently kept in storage facilities and will finally be put into specially engineered underground repositories.


    Nuclear facilities are decommissioned after the end of their operating lives. All nuclear materials, machinery and plant are removed and it is ensured that the site is returned to a state where it can be used for new purposes.


    Nuclear materials, such as feedstock in the fuel manufacture process, new fuel, used fuel and wastes are transported between nuclear facilities by road, rail and sea in specially designed containers. Care is taken to ensure that this is safe even in accident situations.