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Science and technology
科學技術
Solar energy
太陽能
Flower power
花朵的能量
In matters of clever design, nature has often got there first
若論巧奪天工，自然常常更勝一籌
A virtuous spiral
上面的螺紋看似簡單，實際有效
SOLAR-POWER stations take up a lot of room.
太陽能發電站占地面積巨大，
They need either vast arrays of photovoltaic panels, which convert sunlight directly into electricity, or of mirrors,
站內大部分的空間被光伏太陽能板或和定向反射鏡所占據。前者能將光能直接轉換為電能；后者會將太陽熱折射到鍋爐，
which direct it towards a boiler, in order to raise steam and drive a generator.
利用鍋爐將水加熱成蒸汽，驅動發電機組工作，達到熱能轉化為電能的目的。
The space these arrays occupy could often be used for other purposes.
這些整齊排列的面板和鏡身所占的區域通常能用于其它用途。
Two researchers from the Massachusetts Institute of Technology have now devised a better and more compact way of laying out arrays of mirrors.
麻省理工學院的兩位研究員就找出了更好的方法布置定向反射鏡排列，不僅能節約出更多的空間，還能提高發電效率。
Slightly to their chagrin, however, and somehow appropriately,
然而，有點兒讓他們懊惱的是，
they found when they had done the calculations that sunflowers had got there first.
他們計算出的和向日葵花盤型花序上所排列的，大致相同。
Alexander Mitsos and Corey Noone started with the observation that existing concentrated solar-power plants,
Alexander Mitsos和Corey Noone這兩位研究員先從觀察運行中的集中型太陽能發電廠入手。
as those which drive boilers are known, usually have their mirrors arranged in a way that resembles the seating in a cinema.
如大家所知，這些發電廠用太陽能驅動鍋爐做功產生熱量。通常定向反射鏡的安排布置與電影院座椅位置如出一轍。
The mirrors are placed in concentric semicircles facing a tower, on top of which the boiler and the turbine sit.
高塔處于熒屏所在的中心位置，所有的定向反射鏡則以高塔為圓心，呈半圓形分布。
That arrangement, however, sometimes results in the mirrors shading each other as the sun's position in the sky changes,
隨著一天中太陽在天空中位置的變換，鏡身間會出現相互遮擋的問題。
even though the mirrors are usually attached to robotic arms that track the sun as it moves.
即使廠家通常會在鏡身后部安裝能隨太陽位置變換而相應變換的機械手臂，但這一問題還是無法解決。
According to their report in Solar Energy, Dr Mitsos and Mr Noone found that they could do better.
據他們在《太陽能》雜志上發表的文章稱，兩位研究員認為能有方法解決這一難題。
They divided each of the mirrors in a real power plant, PS10, in southern Spain into about 100 pieces.
在一家位于西班牙南部的發電站，PS10中，他們把每一片定向反射鏡的平面面積分為差不多100塊。
They then plugged each of those pieces into a computer model that calculated all of the energy losses
然后將每一片鏡身上的這100多塊面積里產生的吸熱數據接入電腦，通過電腦程序計算出能量損失總和。
by noting points where mirrors were not optimally oriented to the sun and places where they hindered one another by blocking incoming or reflected rays.
這包括鏡身沒能直對太陽造成的損失，以及鏡身位置因相互遮擋使折射光線受阻或反射到鍋爐的光線受阻時造成的損失。
It then rejigged them into a better arrangement.
然后再根據數據重新對鏡身進行排列組合。
Fermat's conjecture
費馬螺線魔力
Previous efforts have been directed mainly at stopping the mirrors shading each other, which tends to mean spreading them out.
在此之前，人們做出了種種努力，但總是在鏡身相互遮擋這一問題上束手無策。而對此常會采用的是展開布局，增加排列面積來避免這種情況出現。
Dr Mitsos and Mr Noone also wanted to save space.
而兩位研究員還想節省面積。
In trying to do so they stumbled on an unusual arrangement that had the desired effect.
為此絞盡腦汁之際，他們無意中發現有一種非常規的排列布局有很好的效果。
When they showed this layout to a third researcher, Manuel Torrilhon of Aachen University in Germany,
他們將這種布局安排展示給另一位研究者，德國亞琛工業大學的Manuel Torrilhon。
he recognised the spiral patterns within it, and this prompted the trio to test a design specifically modelled on nature.
后者認為這種設計中有螺線存在，這促使三位研究者以向日葵花盤型花序為藍本仔細測試設計。
That design was a pattern known as a Fermat spiral, in which each element is set at a constant angle of 137° to the previous one.
他們采用的設計即費馬螺線。即每一個圓在之前一個圓旋轉角度為137度時，折線回旋螺線。
It is most familiar as the arrangement of the florets that make up a sunflower head.
這一排列布置與向日葵花的盤型花序紋路如出一轍。
When the three researchers programmed their model to arrange PS10's mirrors in front of the tower in a segment from such a spiral,
三位研究者按照計劃安排PS10發電廠的鏡身位置，在高塔前，將定向反射鏡呈部分費馬螺線狀布局。
they both improved the efficiency of the collection process and saved space.
結果顯示在吸收太陽熱量的過程中，效率得以提高，占地面積減少。
The improvement in efficiency was, admittedly, quite small,
誠然，效率提高非常有限，
but the space saving was significant—almost 16%.
而空間節省面積卻很高，減少近16%。
If solar power is to make up much of the world's electricity output in future, as supporters of alternative energy hope it will,
如果太陽能如可替代能源支持者所希望的一那樣，在未來成為世界電力的重要來源，
a lot of land will be needed for the power stations.
那么太陽能發電站勢必將需要占據更大的面積。
Reducing that requirement by a sixth, as this discovery promises, would be a big gain.
如果能像此次研究所發現的那樣，有希望將定向反射鏡所占地面積減少六分之一，那么這將是一個巨大的進步。
It would also show that if you look hard enough, there really is nothing new under the sun.
同樣讓我們認識到的是，地球上還有許多未知等待我們認真研究。
