taken from rivers, lakes, and reservoirs in the

採集的所有淡水中有39％

United States is earmarked for the cooling needs

專門用於滿足

of power plants that use fossil fuels

使用化石燃料的發電廠或核電廠

or nuclear power.

的冷卻需求。

The problem?

這造成了什麼問題呢？

A large portion of that water ends up floating away

大量的水最終都飄走進到了

in clouds of vapor.

蒸汽雲中。

In other words, hundreds of billions of gallons

換言之， 每年有數千億加侖

of clean, otherwise usable water are lost each year.

乾淨、可用的水流失。

But now, a new system devised by a team of MIT engineers

但是現在，由麻省理工學院工程師團隊設計的新系統

could provide an efficient, low-cost way

可以提供一種有效、低成本的方法

to capture a substantial amount of that lost water,

來留住那些大量失去的水，

ultimately making power plants less wasteful

最終使發電廠減少浪費

and more self sustaining.

且更加自給自足。

And the water collected could become a source

而收集的水可以成為

of potable water for parched cities around the world.

世界各地炎熱城市的飲用水源。

The motivation to develop this new system

開發這種新系統的動機

stems directly from the inefficiencies

相當直截了當，就是起因於目前

of current natural fog harvesting systems.

天然霧收集系統的低效率。

Existing systems, which generally consist of

現有系統一般是由

a plastic or wire mesh hung vertically in the path

垂直懸掛在霧提路徑上的塑膠或金屬絲網

of fog banks, only capture about one to three percent

所構成，僅能留住通過其

of the water droplets that pass through them.

約百分之一到三的水滴。

The reason for such a tiny percentage is the result

收集到這麼小百分比的原因是

of aerodynamics.

空氣動力學的結果。

As a stream of air passes an obstacle,

當一股氣流通過障礙物，

such as the wires in these mesh fog catching screens,

像是位在捕霧篩網中的金屬絲，

the air flow naturally deviates around the obstacle.

氣流會自然地在障礙物周圍偏離。

Thus, carrying droplets that were heading toward the wire

因此，會帶著朝向金屬絲的液滴

off to the side.

往側邊移動。

The researchers found once they zap the fog

研究人員發現一旦他們用

with a beam of electrically charged particles

被稱為離子的帶電粒子射束急速衝擊霧，

known as ions, the opposite effect happens.

就會發生相反的結果。

Not only do all the droplets that are in the path

不僅金屬絲網路徑上的

of the wires land on them, but even droplets

所有液滴都落在它們上面，甚至連

that were aiming for the holes in the mesh

對準網孔中的液滴

get pulled toward the wires due to the charge.

也會因為電荷而被拉向金屬線。

The droplets then collect on that mesh,

液滴接著會聚集在那個網上，

drain down into a collecting pan,

向下流到收集盤中，

and can be reused in the power plant

並可以在發電廠中重複使用

or sent to a city's water supply system.

或送至城市的供水系統。

The team is currently building a full-scale

該團隊目前正在打造他們系統的

test version of their system,

全方位測試版本，

to be placed on the cooling tower of MIT's

它會被置於麻省理工學院

central utility plant—

中央動力廠房的冷卻塔上──

a natural gas co-generation power plant

這個廠房是天然氣熱電聯產發電廠，

that provides most of the campus's electricity,

提供校園的大部分電力、

heating, and cooling.

暖氣和冷卻。

In a series of experiments, the researchers demonstrated

在一系列的實驗中，研究人員

the concept by building a small lab version

打造了一個小型實驗室的版本──

of a stack emitting a plume of water droplets.

會放射出羽狀水滴的排氣管──來證明這個概念。

They then placed their ion beam and mesh screen on it.

然後他們將離子射束和網篩放在上面。

When the condenser is off, a thick plume of fog droplets

當冷凝器關閉時，一層厚厚的羽狀霧滴

rise from the device.

就會從裝置上升起。

Once the condenser is turned on, the plume

一旦打開冷凝器，羽狀的煙雲

almost instantly disappears and liquid can be seen

幾乎是立即消失，並且可以看到液體

condensing on the wire dome.

冷凝在金屬線罩上。

The equipment is simple, and the amount of power

這個設備很簡單，所需的

required is minimal.

電量也很少。

And the result is something priceless.

結果是無價的。

Access to free, clean water.

得以取得免費、乾淨的水。

The researchers say this could be a great solution

研究人員表示，這會是解決全球水危機

to the global water crisis,

的一個絕佳解決方案，

by offsetting the need for about 70% of new

它可以抵銷未來十年對大約70％的

desalination plant installations in the next decade.

新海水淡化廠安裝的需求。

For example, a typical 600 megawatt power plant

例如，一座標準的600兆瓦發電廠

could capture 150 million gallons of water a year,

每年可以留住1.5億加侖的水，

representing a value of millions of dollars.

這表示其價值有數百萬美元。

The researchers aim to test the system

研究人員的目標是在秋季

at MIT's central utility plant in the fall.

於麻省理工學院的中央動力廠房測試該系統。

The campus's power plant tests will not only

這項校園發電廠測試不僅可以

de-risk the technology, but will also help

降低技術風險，還可以幫助

the MIT campus improve its water footprint.

麻省理工學院校園改善其水足跡。