日期:2022/07/17   IAE 

什麼是核融合Fusion〔小太陽〕？是為太陽提供潔淨安全能量的過程 ！What Is Fusion?

什麼是核融合Fusion〔小太陽〕？

聚變是為太陽提供能量的過程。當我們在極端溫度和壓力下將“輕元素”的原子擠壓（“融合”）在一起時，它們會形成一種新型原子核，並在此過程中向周圍環境釋放一小部分能量。 “輕元素”是原子質量小於鐵原子的材料的原子，包括氫（為太陽提供能量）、氘和氚（用於 STEP）。

阿爾伯特愛因斯坦的最大方程 - E = Δmc2 是聚變產生能量的方式。當兩個源原子融合在一起時，新的單個原子的重量小於兩個源原子的總重量。這種質量差異 (Δm) 以能量 (E) 的形式丟失。該能量的計算方法是將 Δm 乘以光速乘以自身（c2，其中 c = 299,792,458 米/秒）。

由於光速平方的值如此之大，少量的質量損失會導致大量的能量被釋放。這就是STEP產生能量的方式。

What is Fusion?
Fusion is the process that powers the sun. When we squeeze ("fuse") together atoms of "light elements" under extreme temperatures and pressures, they form a new type of atomic nucleus and in the process release a small chunk of energy into the surroundings. "Light elements" are atoms of materials with less atomic mass than an atom of iron, including hydrogen (which powers the Sun), deuterium and tritium (used in STEP).

Albert Einstein's greatest equation -  E = ∆mc2  is the means by which fusion generates energy. When the two source atoms fuse together, the weight of the new single atom is less than the combined weight of the two source atoms. This difference in mass (∆m) is lost as energy (E). This energy is calculated by multiplying ∆m by the speed of light multiplied by itself (c2 where c = 299,792,458 meters per second).

As the value of the speed of light squared is so large, a tiny amount of mass lost results in a very large amount of energy being released. This is how STEP produces energy.

來自融合的力量
與我們可以使用的其他一些方法相比，太陽中的聚變過程效率較低，例如氘（很容易從海水中提取的重水）和氚（可以由鋰產生，在地球上很容易獲得）之間的聚變反應。 D+T 過程通常用於聚變技術中以產生能量，這將是 STEP 使用的過程。

 

Fusion值得努力嗎？
聚變釋放的能量非常可觀——1公斤的聚變燃料——包括從水中產生的氘和從鋰產生的幾克氚，產生的能量與大約10,000,000公斤的煤相同。或者換句話說，半浴缸水中的氘和筆記本電腦電池所產生的電力可以產生足夠人類一生所需的電力。

750px-氘-氚_聚變
 

如果我們有大量可再生能源，為什麼還需要聚變？
氣候變化和能源短缺是一場全球危機。

雖然英國很幸運能夠獲得大量可再生資源（主要是風能），但世界其他地區就沒有這麼幸運了。到 2050 年，即使按照我們目前全球減少碳排放的軌跡，預計 50% 的世界能源仍將來自化石燃料。

除非人類繼續努力開發新的低碳能源生產形式，否則我們的全球危機將持續數十年和數百年，使每個人都面臨氣候變化影響的風險。

雖然聚變無法立即解決所有這些問題，但 STEP 將能夠協助在 2050 年之後進入下個世紀實現淨零碳排放，並與可再生能源和其他零碳能源一起提供寶貴的能源資源。

Power from Fusion
The process of fusion in the Sun is less efficient compared to some other methods we can use, such as the fusion reaction between deuterium (heavy water easily sourced from seawater) and tritium (which can be created from lithium, readily available on Earth). The D+T process is often used in fusion technology to produce energy, and this would be the process used by STEP.

 Is Fusion worth the effort?
The energy released by fusion is significant - 1kg of fusion fuel - comprising of deuterium generated from water and a few grams of tritium generated from lithium, produces the same amount of energy as approximately 10,000,000 kg of coal. Or to put it another way, the electricity generated from the deuterium in half a bathtub of water and a laptop battery can generate enough electricity required by a human over their entire lifetime.

750px-Deuterium-tritium_fusion
 

Why do we need fusion if we have lots of renewable power?
Climate change and energy shortages are a global crisis.

Whilst the UK is fortunate to have access to a large renewable resource (mainly wind), other parts of the world are not so fortunate. In 2050 it is expected that even on our current trajectory to globally reduce carbon emissions, 50% of the worlds energy will still come from fossil fuels.

Unless humans continue to work hard to develop new low carbon forms of energy production, our global crisis will continue for many decades and centuries to come, putting everyone at risk of the impacts of climate change.

Whilst fusion will not be able to solve all these problems immediately, STEP would be able to assist the race to net zero carbon beyond 2050 into the next century and provide a valuable energy resource alongside renewables and other zero carbon energy sources.

這會解決氣候緊急情況嗎？
氣候緊急情況是未來幾十年減少碳排放的迫切需要。然而，隨著交通（電動汽車）和熱能（從天然氣轉向熱泵和電力生產的綠色氫）的持續脫碳，我們將需要繼續尋找解決我們不斷增長的能源需求的解決方案。

STEP 將使我們能夠提前考慮到 2050 年，並為解決 21 世紀下半葉的能源需求做好準備。開發聚變技術仍需要數十年的時間，因此現在是 STEP 為全球能源故事的下一章插上英國國旗的時候了。

到目前為止取得了什麼成就？
核聚變已經研究了 100 多年，但我們現在正處於發展的最後階段，隨著 ITER 等大型實驗解決了一些最終的關鍵挑戰，該技術將達到成熟階段，適合用於STEP等工業發電廠。 Fusion 遵循與其他行業類似的發展速度，例如使用摩爾定律的計算機技術，該定律指出技術進步每 2 年翻一番。聚變技術的進步每 1.8 年翻一番 - 所以是領先於摩爾定律！

UKAEA 一直處於這些進步的最前沿，我們希望通過 STEP 再次引領世界開發新的聚變技術，以幫助解決我們的全球能源挑戰。

Will this solve the Climate Emergency?
The climate emergency is an immediate need to reduce carbon emissions over the coming decades.  However with continued decarbonisation of transport (electric vehicles) and heat (moving from gas to heat pumps and electrically produced green hydrogen), we will need to continue to find solutions to our ever increasing energy demands.

STEP will allow us to think ahead to 2050 and get prepared to solve our energy needs in the second half of the 21st century. Developing fusion technology will still take a number of decades, so now is the time for STEP to plant the UK's flag in the ground for the next chapter in the global energy story.

What has been achieved so far?
Nuclear fusion has been studied for over 100 years, however we are now reaching the final stages of development, and as large experiments such as ITER solve some of the final key challenges, the technology will reach a stage of maturity where it will be suitable for use in an industrial power generation plant such as STEP. Fusion follows similar rates of development to other industries such as computer technology which uses Moore's Law which states technology advancements double every 2 years. Fusion technology advancements are doubling every 1.8 years - so is ahead of Moore's Law!

UKAEA has always been at the forefront of these advancements and with STEP we hope to once again lead the world in the development of new fusion technology to help solve our global energy challenges.