FT雙語筆記|文都提醒：新能源領域留學需謹慎

Seaweed, the great green hope?

Modern biofuels have been touted as a greener alternative to petrol and diesel since the early 1900s. It seems like a good idea on paper, and they do work – but their use and production doesn』t come without problems.

自20世紀初開始，現代生物燃料就被奉為可以替代汽油和柴油的環保燃料。理論上來講，這似乎是個不錯並且行之有效的主意（觀點）——但是生物燃料的使用和生產並非沒有問題。

The first generation of biofuels – mainly ethanol made from plant crops – and second generation, derived from plant and animal waste streams（名詞）, both had environmentalists and others concerned about the competition for land and nutrients between biofuels production and food production.

無論是第一代生物燃料——主要是以農作物為原料製造的乙醇——還是利用動物排泄物和植物製成的第二代生物燃料，都有環境保護人士擔心生物燃料生產可能會與糧食種植競爭土地和養分。

It was with a lot of hope, and hype, that production of the third generation of biofuels was started. Unlike their predecessors, these biofuels are derived from algae, and so in theory the food vs fuel dilemma of crop-based biofuels would be solved.

第三代生物燃料於是在人們的殷切希望和大肆的宣傳中登場。與前兩代生物燃料不同，第三代生物燃料以藻類（名詞）為原料，因此在理論上解決了此前以農作物為原料的生物燃料與糧食生產之間可能產生的競爭問題。

Fossil fuel oil and gas originated from ancient algae in large measure, so the concept here is to replicate the essence（小詞）of the creation of fossil fuels, albeit accelerated and optimised with modern chemical engineering. It was claimed that using algae would be much more efficient than creating biofuels from terrestrial plants and that the technology would make use of poor quality land not able to grow other crops.

石油天然氣很大程度上（句型）就是來自遠古時代的藻類，因此利用藻類生產生物燃料實際上就是要以現代化學工程技術優化過的技術，複製並加速化石燃料生產的過程。據稱，用藻類生產生物燃料比用地表植物生產生物燃料更為高效，並且這項技術還可以很好地利用無法種植其他農作物的貧瘠土地。

Millions of dollars, euros and other currencies have been spent trying to get the algal marvel to work. Much of the money has been directed at refining the engineering process, electrically lighting the crop – which grows in a liquid suspension – harvesting and draining it. The solution to optimisation was seen as primarily technological non-biological, though species selection and growth conditions werealso acknowledged as important factors.

美歐以及其他一些國家已經在藻類生物能源的研究開發中（小詞）投入了大量資金。這些錢中有很大一部分用在了改進工藝流程、為生長在培養液（名詞）中的藻類提供電力照明、以及水藻的收穫和乾燥。優化解決方案基本上是利用了非生物技術，不過藻類品種的選擇以及生長環境也被認為（句型）是重要的因素。

However, it turns out that the hype has been misplaced. Our research has found that the production of algal biofuels is neither commercially nor environmentally sustainable. The attainable production levels are a fraction of those that were claimed. The amount of biofuel produced from prolonged culture of algae in pilot-scale systems is actually not too dissimilar from those of terrestrial plants: around 5,000 to 10,000 litres per hectare per year.

但結果證明，生物燃料不過是盛名之下其實難副（四字）。我們的研究發現，無論是從商業角度，還是從環保的角度，藻類生物燃料的生產都不具備可持續性。目前可以達到的生產規模遠遠小於（句型）此前聲稱的。實際上，從生物燃料的產量上來說，以經過長時間培養的藻類為原料的試點系統與以陸生植物為原材料的傳統方法差別不大：每公頃年產量都是5000到10000升左右。

In fact, the rate of production from algae growing in the vast ponds required for truly massive production is, for a given area of land, similar to that seen in the most productive areas of the ocean. It amounts to around 4g of carbon from CO₂ fixed into biomass per square metre every day.

實際上，達到真正的量產規模后，以大面積水域中生長的藻類為原料的單位面積生產率與我們所見的海洋中自然藻類生長最密集的地方類似。數量上相當於每天每平方米藻類固定4克來自二氧化碳中的碳元素。

So what』s the problem? Why aren』t algal biofuels as good as had been hoped? Quite simply, it』s biology.

那麼問題究竟出在哪裡？為什麼藻類生物燃料並沒有達到人們的預期？其實答案很簡單：這就是生物的規律。

The dream has been broken not by failings in engineering, but by the inefficiency of biochemistry. Simulations of microalgal biofuel production show that to approach the 10% of EU transport fuels expected to be supplied by biofuels, ponds three times the area of Belgium would be needed. And for the algae in these ponds to produce biofuel, it would require fertiliser equivalent to 50% of the current total annual EU crop plant needs. Ironically, such ponds would also need to be located near heavy industry which produces CO₂ to provide the level required by the microalgae for photosynthesis.

打破藻類生物燃料夢想的並非工程設計上的缺陷，而是（句型）生物化學本身的低效。對微藻生物燃料生產的模擬表明，如果要用生物燃料替代歐盟10%的交通燃料，需要一個三倍於比利時國土面積的水域。並且要使這片水域中生長的藻類可以用來生產生物燃料，所施用的化肥量相當於目前歐盟地區糧食種植所需化肥總量的一半。諷刺的是，這片水域還需要臨近重工業區（補"區"字），因為只有這樣，微藻才能獲得完成光合作用所需的二氧化碳。

The problem with third-generation biofuels has always been scaling up the production rates measured in small culture flasks to growth in thousands of cubic metres in size. In the larger cultures, the biomass density of the algae – needed to make the culture and harvesting processes economical – defeats desired growth rates because the organisms shade light from each other. This means that they do not get the sunlight needed to photosynthesise and produce the carbon-rich compounds needed for to make the biofuel fast enough.

第三代生物燃料所面臨的問題一直在於無法在規模化生產（辭彙）中複製培養瓶中測得的生產率。在規模更大的培養環境中，為了確保藻類的培養和收穫流程具有經濟性，就必須到達一定的生物質密度，如此一來就很難達到理想的生長率。因為密度過高使各有機體之間出現相互遮蓋的現象，這意味著它們無法獲得光合作用（辭彙）所需的光照，無法製造出富含碳元素的化合物，從而無法以足夠快的速度製造生物燃料。

There have also been misunderstandings of how the algae react to their environment. Importantly, those vital carbon-rich compounds only really accumulate in cells that are nitrogen-limited and so are growing slowly. Early production estimates assumed high carbon-rich content in fast-growing cells but this has not proved to be the case（句型）.

人們對於藻類如何應對環境的變化也存在一些誤解。其中重要的一項在於，那些重要的富碳化合物只累積於限氮環境的細胞中，而此類細胞因為限氮的緣故生長緩慢。早期的生產試驗中假設富碳物質在快速生長的細胞中高水平累積，但實踐證明事實並非如此。

Could we not genetically modify a solution to the inherent biological inefficiency? Perhaps, but should we really tamper with factors that are so fundamental to life on Earth and risk generating unstoppable harmful algal species that could destroy fisheries and damage drinking water supplies? Even if we did create the perfect algae for biofuels production, the need for all that fertiliser and CO₂ would remain.

對於生物機能本身的低效，我們難道不能通過基因改造的方式解決嗎？也許可以，但我們是否真的應該篡改對於地球上的生命具有如此重要基礎意義的因素，冒著破壞漁業和水資源供應的風險，製造出勢不可擋的有害藻類物種？即使我們真的創造出能夠用於生產生物燃料的完美藻類，還是沒法解決藻類生物燃料生產需要大量化肥和二氧化碳的問題。

Ultimately the public have paid for this failedvision – but their money has not been wasted. If there』s one thing that humans need more than fuel it is food – and this work can help us understand how to better grow microalgae to support the farming of fish and shellfish, and produce dietary supplements（辭彙）, like Omega-3. Mass microalgal production could also create food containing omega fatty acids to farmed fish, for example, meaning that we would no longer need to fish in rivers and oceans to make fishmeal for them.

最終，公眾為這項落空的願景買了單，但他們的錢並沒有打水漂。人類對於一件東西的需求超過了燃料，那就是食物——而關於藻類生物燃料的研究可以幫助我們理解如何才能通過更好地種植微藻來支持魚類和貝類的養殖，以及如何更好地製造Omega-3等膳食補充劑。例如，大規模微藻生產可以為人工養殖的魚類提供富含Omega脂肪酸（辭彙）的食物，這意味著我們不需要再打撈河魚和海魚製作魚食了。

The future for mass microalgal cultivation is still literally and metaphorically green, it just does not rest with biofuels production.不管怎樣，未來大規模微藻養殖仍然屬於（句型）綠色產業，只不過生物燃料生產將不再是其立足點（句型）而已。