日期:2022/09/16 IAE 報導
在一個對更多、更清潔能源的需求不斷增長的世界中，迫切需要替代選擇。 50 年來，利用聚變（為太陽提供能量的過程）為我們提供能量一直是科學夢想，但現在它已接近技術現實。
Fusion 是一種安全且環保的能源選擇，提供了可持續和長期能源供應的可能性。在核聚變發電廠中，能量是通過將兩個輕原子（氘和氚 - 氫的同位素）的核融合在一起產生的。聚變中使用的主要燃料是氘和鋰。氘很容易從水中提取（每立方米水中約有 30 克氘），而鋰是一種豐富的輕金屬，可用於在發電廠內產生氚。一個筆記本電腦電池中的鋰和水浴中的氘可以提供一個人30年所需的總電量。這相當於 40 噸煤產生的能量。
“其他吸引人的特點是該過程不會產生任何溫室氣體，例如二氧化碳或長期放射性廢物”，UKAEA Culham 主任 Chris Llewellyn Smith 說。 “與一些替代能源不同，它適用於大規模發電——無論風雨無阻，每天都在生產基荷電力。”
為了使聚變發生，稱為託卡馬克的實驗裝置被用來將氣體（或等離子體）加熱到 150-2 億攝氏度的溫度 - 比太陽中心高十倍。等離子體遠離設備的壁，並被強大的磁場擠壓在一起。 UKAEA 的 Culham 科學中心舉辦了世界上最大的聚變實驗 - JET（聯合歐洲圓環），它是目前 16 兆瓦聚變功率的世界紀錄保持者。
傳統的託卡馬克——比如 JET——有一個環形的腔室來容納等離子體； Culham 的另一個設備 - MAST - 是球形託卡馬克。 MAST 的等離子室更像是一個“有核蘋果”。 “球形託卡馬克比傳統託卡馬克小”，克里斯說。 “而且它們還有一些其他的運行特性，可以使它們作為發電廠具有吸引力。”
英國政府已經認識到聚變在未來能源結構中提供很大一部分的潛力。
概述
Chris Llewellyn Smith 爵士 FRS 教授、Chris Carpenter 先生、Heather Clark 夫人和 Jennifer Hay 夫人。
UKAEA 庫勒姆科學中心。
Overview
Professor Sir Chris Llewellyn Smith FRS, Mr Chris Carpenter, Mrs Heather Clark and Mrs Jennifer Hay.
UKAEA Culham Science Centre.
In a world with increasing demands for more, cleaner energy, alternative options are urgently needed. Using fusion - the process that powers the Sun - to supply our energy has been a scientific dream for 50 years, but now it is close to a technical reality.
Fusion is a safe and environmentally friendly energy option offering the possibility of a sustainable and long-term energy supply. In a fusion power plant energy is generated by fusing together the nuclei of two light atoms (deuterium and tritium - isotopes of hydrogen). The primary fuels used in fusion are deuterium and lithium. Deuterium is readily extracted from water (there are around 30 g of deuterium in every cubic metre of water), and lithium is an abundant light metal that is used to generate tritium inside the power plant. The lithium from one laptop battery together with the deuterium from a bath of water could supply the total electricity needed by one person for 30 years. This is the equivalent of the energy produced by 40 tons of coal.
'Other attractive features are that the process does not generate any greenhouse gases, such as carbon dioxide, or longterm radioactive waste', says UKAEA Culham Director Chris Llewellyn Smith. 'Unlike some alternative energy sources it is suitable for large-scale generation of electricity - producing baseload electricity all day and every day, rain or shine.'
To get fusion to happen, experimental devices called tokamaks are used to heat a gas (or plasma) to temperatures of 150-200 million °C - ten times hotter than the centre of the Sun. The plasma is kept away from the walls of the device and squeezed together by powerful magnetic fields. The UKAEA's Culham Science Centre hosts the world's largest fusion experiment - JET (Joint European Torus), the current world record holder for fusion power at 16 megawatts.
Conventional tokamaks - like JET - have a doughnut-shaped chamber to hold the plasma; another device at Culham - MAST - is a spherical tokamak. MAST's plasma chamber is more like a 'cored apple'. 'Spherical tokamaks are smaller than conventional tokamaks', says Chris. 'And they have some other operational characteristics that could make them attractive as power plants.'
The UK Government has recognised the potential of fusion to supply a large proportion of the future energy mix.
A star is born - fusion powering your future