Some years ago, I set out to try to understand

是否有辦法生產生質能源

if there was a possibility to develop biofuels

使之量大到可與石化燃料抗衡

on a scale that would actually compete with fossil fuels

卻不會與食用農業競爭水、肥料、或是土地

but not compete with agriculture for water,

卻不會與食用農業競爭水、肥料、或是土地

fertilizer or land.

以下是我想出來的方案

So here's what I came up with.

想像一個建造在水底下的空間

Imagine that we build an enclosure where we put it

我們把它裝滿處理過的廢水

just underwater, and we fill it with wastewater

並加入會製造油料的微藻

and some form of microalgae that produces oil,

然後這個空間的材料將會是有彈性的

and we make it out of some kind of flexible material

讓它能夠隨波移動

that moves with waves underwater,

當然，我們建造的這個系統

and the system that we're going to build, of course,

將利用太陽能使藻類生長

will use solar energy to grow the algae,

它們會消耗二氧化碳，這是件好事

and they use CO2, which is good,

然後在生長的過程中製造氧氣

and they produce oxygen as they grow.

微藻生長的空間能夠將多餘的熱能

The algae that grow are in a container that

分散傳導至四周圍的水中

distributes the heat to the surrounding water,

你可以收成它們來提煉生質能源

and you can harvest them and make biofuels

還有化妝品、肥料、及飼料的原料

and cosmetics and fertilizer and animal feed,

當然，你得讓它附蓋很大的面積

and of course you'd have to make a large area of this,

所以你得當心其他利益相關者

so you'd have to worry about other stakeholders

像是漁民和船等等，但這都是小事

like fishermen and ships and such things, but hey,

因為重要的是生質能源

we're talking about biofuels,

而大家都知道生產替代能源是多麼的重要

and we know the importance of potentially getting

而大家都知道生產替代能源是多麼的重要

an alternative liquid fuel.

為什麼我們要用微藻類?

Why are we talking about microalgae?

這個圖表顯示著目前考慮

Here you see a graph showing you the different types

用來生產生質能源的不同農作物

of crops that are being considered for making biofuels,

你可以看到像是黃豆

so you can see some things like soybean,

每英畝一年可生產五十加侖

which makes 50 gallons per acre per year,

或是向日葵、油菜籽、痲瘋樹、和油棕

or sunflower or canola or jatropha or palm, and that

然後那個很高的圖代表微藻的產量

tall graph there shows what microalgae can contribute.

和黃豆的五十加侖產量相比

That is to say, microalgae contributes between 2,000

微藻每英畝可在一年內生產

and 5,000 gallons per acre per year,

兩千至五千加侖的油

compared to the 50 gallons per acre per year from soy.

微藻是什麼?微藻是微生物

So what are microalgae? Microalgae are micro --

也就是說，他們很微小

that is, they're extremely small, as you can see here

你可以看看這些單細胞生物

a picture of those single-celled organisms

和頭髮大小相比的照片

compared to a human hair.

這些微生物已經存在幾百萬年了

Those small organisms have been around

而且世界各地有上千種

for millions of years and there's thousands

不同種類的微藻

of different species of microalgae in the world,

其中有些是世界上生長最快的植物

some of which are the fastest-growing plants on the planet,

並生產，就如我剛剛所說的，很多很多油

and produce, as I just showed you, lots and lots of oil.

那為什麼我們選擇在沿岸做這個計劃?

Now, why do we want to do this offshore?

選擇在都市沿岸的原因在於

Well, the reason we're doing this offshore is because

如果你觀察沿海都市，會發現其實別無選擇

if you look at our coastal cities, there isn't a choice,

這是因為如我剛剛提到，我們將利用廢水

because we're going to use waste water, as I suggested,

如果你看看我們的廢水處理廠的位置

and if you look at where most of the waste water

它們都在城市附近

treatment plants are, they're embedded in the cities.

這是舊金山，它地底已埋了

This is the city of San Francisco, which has 900 miles

總長約九百英里的廢水管

of sewer pipes under the city already,

並將這些廢水排放到海裡

and it releases its waste water offshore.

世界各地的都市處理廢水的方式各有不同

So different cities around the world treat their waste water

有些都市會加以處理

differently. Some cities process it.

有些都市會直接排放

Some cities just release the water.

但是無論如何，排出的廢水

But in all cases, the water that's released is

對於提供微藻生長是完全沒問題的

perfectly adequate for growing microalgae.

所以讓我們想想這個系統會長什麼樣子

So let's envision what the system might look like.

我們叫它OMEGA，它是

We call it OMEGA, which is an acronym for

「沿岸微藻生長包膜」的縮寫 (Offshore Membrane Enclosures for Growing Algae)

Offshore Membrane Enclosures for Growing Algae.

在NASA，有好的縮寫是很重要的

At NASA, you have to have good acronyms.

它將如何運作? 我剛剛已經敘述了大概

So how does it work? I sort of showed you how it works already.

我們輸入廢水和某二氧化碳源

We put waste water and some source of CO2

進入這些漂浮的結構中

into our floating structure,

然後廢水提供微藻生長所需的養分

and the waste water provides nutrients for the algae to grow,

而微藻消耗並固著二氧化碳

and they sequester CO2 that would otherwise go off

減少溫室氣體

into the atmosphere as a greenhouse gas.

它們當然是利用太陽能生長

They of course use solar energy to grow,

然後海浪會提供動能混合藻類

and the wave energy on the surface provides energy

而溫度將會由周圍的水溫所控制

for mixing the algae, and the temperature

而溫度將會由周圍的水溫所控制

is controlled by the surrounding water temperature.

就如我所提的，藻類將生產氧氣

The algae that grow produce oxygen, as I've mentioned,

它們也會生產生質能源和肥料、食物

and they also produce biofuels and fertilizer and food and

以及其他藻類生物副產品

other bi-algal products of interest.

而且這整個系統是自我封閉的。這是麼意思?

And the system is contained. What do I mean by that?

它是模塊化的。假設其中一個單元

It's modular. Let's say something happens that's

出乎意料外的停擺

totally unexpected to one of the modules.

它漏水了，或被閃電擊中

It leaks. It's struck by lightning.

流出來的廢水是原本就會被排放到海域的

The waste water that leaks out is water that already now

流出來的廢水是原本就會被排放到海域的

goes into that coastal environment, and

而那些藻類是會自然分解的

the algae that leak out are biodegradable,

因為它們原本存活於廢水中

and because they're living in waste water,

它們是淡水藻，這意味著

they're fresh water algae, which means they can't

它們無法於鹹水中生存，所以會死去

live in salt water, so they die.

我們將使用的塑膠材料

The plastic we'll build it out of is some kind of

是一種廣泛使用的材料，效果良好

well-known plastic that we have good experience with, and

而且我們將設計這些單元，使之能重複使用

we'll rebuild our modules to be able to reuse them again.

所以我們有可能超越現況思考

So we may be able to go beyond that when thinking about

來考慮這個系統的用途，我的意思是

this system that I'm showing you, and that is to say

我們需要考慮淡水的問題

we need to think in terms of the water, the fresh water,

淡水在未來將會是個急迫的課題

which is also going to be an issue in the future,

所以我們現在正研究開發

and we're working on methods now

重複利用廢水的方法

for recovering the waste water.

另外需要考慮的一點是架構本身

The other thing to consider is the structure itself.

它將在海洋中為生物提供表面積

It provides a surface for things in the ocean,

這些表面會被海藻占滿

and this surface, which is covered by seaweeds

還有海洋中的其他生物

and other organisms in the ocean,

它將提升海洋的棲地生態

will become enhanced marine habitat

並增加生物多樣性

so it increases biodiversity.

最後，因為它是在海岸邊的架構

And finally, because it's an offshore structure,

我們可以想像它如何能夠增進

we can think in terms of how it might contribute

海岸的水產養殖活動

to an aquaculture activity offshore.

所以你大概在想 "天啊

So you're probably thinking, "Gee, this sounds

這聽起來真是個好主意，我們如何試試看它能否成真?"

like a good idea. What can we do to try to see if it's real?"

我已在Santa Cruz設立實驗室

Well, I set up laboratories in Santa Cruz

在加州漁獵部的場地

at the California Fish and Game facility,

那裡有設施提供我們設立大型的海水箱

and that facility allowed us to have big seawater tanks

來測試這些想法

to test some of these ideas.

我們同時於舊金山設立實驗

We also set up experiments in San Francisco

在那三個廢水處理廠其中之一

at one of the three waste water treatment plants,

一樣來試驗我們的提案

again a facility to test ideas.

最後，我們想看看要在哪裡

And finally, we wanted to see where we could look at

能夠測試這個架構對海洋環境的影響

what the impact of this structure would be

所以我們設立了一個野地實驗

in the marine environment, and we set up a field site

在一個叫 Moss Landing 海洋實驗室的地方

at a place called Moss Landing Marine Lab

位於蒙特利灣，我們在海港內實驗

in Monterey Bay, where we worked in a harbor

看看這對海洋生物的影響會是什麼

to see what impact this would have on marine organisms.

在 Santa Cruz 的實驗室是我們的開發中心

The laboratory that we set up in Santa Cruz was our skunkworks.

我們在那裡培養藻類

It was a place where we were growing algae

融合塑膠、建造工具

and welding plastic and building tools

和出了很多差錯

and making a lot of mistakes,

或是如艾迪生所說的

or, as Edison said, we were

我們正發現這系統無法運作的一萬個原因

finding the 10,000 ways that the system wouldn't work.

所以我們在廢水中養微藻，並設計工具

Now, we grew algae in waste water, and we built tools

讓我們能夠融入藻類生活

that allowed us to get into the lives of algae

密切監測它們成長的方式

so that we could monitor the way they grow,

看如何讓它們開心生活

what makes them happy, how do we make sure that

以確保我們培養的藻類能夠生存茁壯

we're going to have a culture that will survive and thrive.

而我們最迫切需要設計的東西

So the most important feature that we needed to develop were these

是這些生物光合反應器，我們簡稱PBR (photobioreactor)

so-called photobioreactors, or PBRs.

這些就是將會漂浮於海面的結構

These were the structures that would be floating at the

用某種便宜的塑膠材料製作

surface made out of some inexpensive plastic material

使微藻能在其中成長，而我們也測試了

that'll allow the algae to grow, and we had built lots and lots

許許多多不同的設計，大多都是失敗的作品

of designs, most of which were horrible failures,

當我們找到一個成功的設計

and when we finally got to a design that worked,

在約三十加侖的大小

at about 30 gallons, we scaled it up

我們在舊金山把它放大到450加侖測驗

to 450 gallons in San Francisco.

讓我告訴你這系統如何運作

So let me show you how the system works.

我們基本上採用內含經挑選的藻類的廢水

We basically take waste water with algae of our choice in it,

並將之循環通過這個漂浮的結構

and we circulate it through this floating structure,

這個管狀、有彈性的塑膠結構

this tubular, flexible plastic structure,

然後它將在這裡面循環

and it circulates through this thing,

當然，太陽光會照在表面

and there's sunlight of course, it's at the surface,

然後藻類吸取養份成長

and the algae grow on the nutrients.

但這有點像把你的頭塞到塑膠袋裡

But this is a bit like putting your head in a plastic bag.

雖然藻類並不會像我們一樣因二氧化碳而窒息

The algae are not going to suffocate because of CO2,

雖然藻類並不會像我們一樣因二氧化碳而窒息

as we would.

但它們會因製造的氧氣而窒息

They suffocate because they produce oxygen, and they

它不是真的會窒息，但是它們產生的氧氣是個問題

don't really suffocate, but the oxygen that they produce

因為它們會把二氧化碳用完

is problematic, and they use up all the CO2.

所以我們的下一步便是想辦法移除氧氣

So the next thing we had to figure out was how we could

我們加了這個柱狀體

remove the oxygen, which we did by building this column

用來循環部分的水

which circulated some of the water,

並重新加入二氧化碳，我們再循環水之前

and put back CO2, which we did by bubbling the system

灌注氣泡在裡頭，解決問題

before we recirculated the water.

你再這裡看見的昰初成品

And what you see here is the prototype,

是我們第一次試著建造這個柱狀物

which was the first attempt at building this type of column.

我們將大型的柱狀結構安裝於舊金山

The larger column that we then installed in San Francisco

在我們安裝的系統裡

in the installed system.

這個柱狀的構造還有一個優點

So the column actually had another very nice feature,

就是藻類會沉澱到柱子底部

and that is the algae settle in the column,

這使我們能夠累積微藻體積

and this allowed us to accumulate the algal biomass

並方便收成

in a context where we could easily harvest it.

我們可以將累積於柱子底部的微藻移除

So we would remove the algaes that concentrated

我們可以將累積於柱子底部的微藻移除

in the bottom of this column, and then we could

然後讓它漂浮在水中，再用網子從表面撈取

harvest that by a procedure where you float the algae

以大量收成

to the surface and can skim it off with a net.

我們也想要了解這個結構

So we wanted to also investigate what would be the impact

對於海洋環境的影響

of this system in the marine environment,

而我之前提到我們有實際於野外實驗

and I mentioned we set up this experiment at a field site

在Moss Landing海洋實驗室

in Moss Landing Marine Lab.

我們理所當然地發現這些材料

Well, we found of course that this material became

會被海藻覆蓋，所以我們需要

overgrown with algae, and we needed then to develop

設計一個清潔的方法

a cleaning procedure, and we also looked at how

我們也觀察海洋哺乳類和鳥類的與此互動

seabirds and marine mammals interacted, and in fact you

你在這裡可見一隻海獺對這個挺有興趣的

see here a sea otter that found this incredibly interesting,

牠不時地於這個迷你水床中穿梭

and would periodically work its way across this little

我們好想要雇用這個小傢伙

floating water bed, and we wanted to hire this guy

或訓練他幫我們清理這些結構的表面之類的

or train him to be able to clean the surface

但那是未來的事

of these things, but that's for the future.

所以我們真正在做的昰

Now really what we were doing,

我們於四個方面進行研究

we were working in four areas.

我們的研究範圍包含這個系統的生物方面

Our research covered the biology of the system,

像是研究藻類的生長方式

which included studying the way algae grew,

什麼東西會吃掉微藻，還有什麼東西會殺死它

but also what eats the algae, and what kills the algae.

我們於工程方面了解我們需要什麼材料

We did engineering to understand what we would need

來建造整個結構

to be able to do to build this structure,

不止是小規模，而是如何建造

not only on the small scale, but how we would build it

我們最終需要的極大規模的成品

on this enormous scale that will ultimately be required.

我有提到我們研究鳥類和海洋哺乳類

I mentioned we looked at birds and marine mammals

並基本上全面評估它的環境影響

and looked at basically the environmental impact

最後我們解決經濟方面的問題

of the system, and finally we looked at the economics,

我所指的經濟是

and what I mean by economics is,

這系統需要多少能源來運作?

what is the energy required to run the system?

你能夠從系統提出

Do you get more energy out of the system

比你所輸入還要更多的能源嗎?

than you have to put into the system

比你所輸入還要更多的能源嗎?

to be able to make the system run?

它的運作成本多少?

And what about operating costs?

它需要多少資本?

And what about capital costs?

它整體的經濟架構穩固嗎?

And what about, just, the whole economic structure?

讓我告訴你這將不會是簡單的事

So let me tell you that it's not going to be easy,

我們在這四個方面都還有很多努力空間

and there's lots more work to do in all four

才有辦法讓這個系統真正運作

of those areas to be able to really make the system work.

但是我們時間不多，所以我想給你看

But we don't have a lot of time, and I'd like to show you

我們預計這個系統將會如何呈現

the artist's conception of how this system might look

於一個想像的海灣

if we find ourselves in a protected bay

在世界的某處，在背景中

somewhere in the world, and we have in the background

可見廢水處理廠

in this image, the waste water treatment plant

以及提供二氧化碳的排氣煙囪

and a source of flue gas for the CO2,

但是當你算算系統的經濟收支

but when you do the economics of this system,

你會發現僅這樣是很難運作的

you find that in fact it will be difficult to make it work.

除非你把這系統想成廢水處理的替代方式

Unless you look at the system as a way to treat waste water,

並有固碳、結合太陽發電

sequester carbon, and potentially for photovoltaic panels

或是海潮發電、風力發電等可能性

or wave energy or even wind energy,

如果你開始思考

and if you start thinking in terms of

如何結合各式各樣的活動

integrating all of these different activities,

你也可以在這個系統加入水產養殖

you could also include in such a facility aquaculture.

像是在這個系統底下我們有貝類養殖

So we would have under this system a shellfish aquaculture

可以生產蛤蠣或是淡菜

where we're growing mussels or scallops.

我們可以生產生蠔等等

We'd be growing oysters and things

可以提高經濟價值的食物和產品

that would be producing high value products and food,

然後利用這點來刺激市場

and this would be a market driver as we build the system

慢慢把系統越做越大，直到最後

to larger and larger scales so that it becomes, ultimately,

將之作為生產生質燃料來源的理由才有競爭力