Donald Sadoway: The missing link to renewable energy

譯者: Regina Chu 審譯者: Wang-Ju Tsai

The electricity powering the lights in this theater

點亮這個劇院有燈光所需的電力

was generated just moments ago.

剛剛才從發電廠產生

Because the way things stand today,

依目前電力使用的狀況

electricity demand must be in constant balance

電力需求必須與電力供應

with electricity supply.

持續取得平衡

If in the time that it took me to walk out here on this stage,

如果在我走上台的這段時間

some tens of megawatts of wind power

數百兆瓦的風力發電

stopped pouring into the grid,

停止輸送給輸電網路的話

the difference would have to be made up

這個不足

from other generators immediately.

該由其他的發電機立刻補上

But coal plants, nuclear plants

但是火力發電廠 核能發電廠

can't respond fast enough.

都不能立即增產做出反應

A giant battery could.

巨大的電池卻可以

With a giant battery,

用巨大的電池儲能

we'd be able to address the problem of intermittency

可以讓我們解決風力及太陽能發電

that prevents wind and solar

這種間歇性發電法

from contributing to the grid

所產生的供電波動的問題

in the same way that coal, gas and nuclear do today.

進而達到跟火力 天然氣 及核能一樣可以持續供電

You see, the battery

你看 電池

is the key enabling device here.

在這裡是個關鍵

With it, we could draw electricity from the sun

使用電池儲能 即使沒有太陽光

even when the sun doesn't shine.

我們仍可使用太陽能所產生的電力

And that changes everything.

而這將改變一切

Because then renewables

因為這麼做 使得可再生能源

such as wind and solar

像是風力及太陽能

come out from the wings,

不再是配角

here to center stage.

而成為主流

Today I want to tell you about such a device.

今天我要介紹一種新裝置

It's called the liquid metal battery.

叫做液態金屬電池

It's a new form of energy storage

這種新型態的能源儲存技術

that I invented at MIT

是我及我在麻省理工學院的

along with a team of my students

學生和博士後研究團隊

and post-docs.

發明的

Now the theme of this year's TED Conference is Full Spectrum.

今年的TED研討會的主題為全光譜

The OED defines spectrum

牛津英語詞典對光譜一詞的定義是

as "The entire range of wavelengths

所有波長範圍的

of electromagnetic radiation,

電磁波

from the longest radio waves to the shortest gamma rays

涵蓋從波長最長的無線電波到最短的伽瑪射線

of which the range of visible light

而可見光

is only a small part."

只是其中的一小部分

So I'm not here today only to tell you

所以今天我在這裡 不僅要告訴你們

how my team at MIT has drawn out of nature

我在麻省理工的團隊

a solution to one of the world's great problems.

如何解決這個世界最大的問題

I want to go full spectrum and tell you how,

我還要全方位解說

in the process of developing

發展此項新科技

this new technology,

的過程

we've uncovered some surprising heterodoxies

我們發現了幾件令人驚訝的事實

that can serve as lessons for innovation,

與一般認知相異 可以為發明家的鑑鏡

ideas worth spreading.

的確是值得傳播的好點子（TED標語）

And you know,

眾所皆知

if we're going to get this country out of its current energy situation,

如果我們要解決這個國家所面對的能源問題

we can't just conserve our way out;

我們不能只靠節約能源

we can't just drill our way out;

我們不能只靠鑽探能源

we can't bomb our way out.

我們也不能只靠開採能源

We're going to do it the old-fashioned American way,

我們要用傳統的美國作法

we're going to invent our way out,

我們要攜手合作

working together.

發明能源

(Applause)

（掌聲）

Now let's get started.

言歸正傳

The battery was invented about 200 years ago

電池是在約200年前

by a professor, Alessandro Volta,

由亞力山卓伏特教授所發明

at the University of Padua in Italy.

他當時在義大利帕度亞大學任教

His invention gave birth to a new field of science,

他的發明孕育了一門新的科學

electrochemistry,

即電化學

and new technologies

以及像電鍍這樣的

such as electroplating.

新科技

Perhaps overlooked,

綜觀歷史

Volta's invention of the battery

伏特發明電池這件事

for the first time also

也許也是第一次證明了

demonstrated the utility of a professor.

教授的用處

(Laughter)

（笑聲）

Until Volta, nobody could imagine

在伏特發明電池以前

a professor could be of any use.

沒有人知道到底教授有什麼用處

Here's the first battery --

這個世上最早的電池

a stack of coins, zinc and silver,

用銅板 鋅板 及銀堆疊而成

separated by cardboard soaked in brine.

其中夾著浸鹽水的紙板

This is the starting point

這是電池設計的

for designing a battery --

起始點

two electrodes,

兩端電極

in this case metals of different composition,

在這裡是兩種不同的金屬

and an electrolyte,

以及電解質

in this case salt dissolved in water.

在這裡是鹽水

The science is that simple.

科學原理就是這麼簡單

Admittedly, I've left out a few details.

我承認我省略了一些細節

Now I've taught you

我之前已經說了

that battery science is straightforward

電池的科學原理其實很簡單明瞭

and the need for grid-level storage

而我們對電網層級的大型儲電系統

is compelling,

需求很大

but the fact is

但事實是

that today there is simply no battery technology

現今沒有任何電池科技

capable of meeting

能達到

the demanding performance requirements of the grid --

電網所需的儲能負載條件

namely uncommonly high power,

就是要能負載非常高的電力

long service lifetime

要有很長的使用壽命

and super-low cost.

及極低的成本

We need to think about the problem differently.

所以我們要用不同的角度看問題

We need to think big,

就是規模要大

we need to think cheap.

價錢要便宜

So let's abandon the paradigm

所以就讓我們捨棄

of let's search for the coolest chemistry

先找出最酷的化學方程式

and then hopefully we'll chase down the cost curve

然後希望以大量生產的方法

by just making lots and lots of product.

來降低成本這種思維

Instead, let's invent

反之 讓我們發明

to the price point of the electricity market.

以現有電價就能負擔的材料

So that means

但如此一來

that certain parts of the periodic table

週期表裡的某些元素

are axiomatically off-limits.

就理當排除在外了

This battery needs to be made

這個電池需要

out of earth-abundant elements.

用藴藏豐富的元素來製造

I say, if you want to make something dirt cheap,

我是說 如果你要製作像土一樣便宜的東西

make it out of dirt --

就用土來做吧

(Laughter)

（笑聲）

preferably dirt

最好是找

that's locally sourced.

當地出產的土（美國人對有機農業的笑話）

And we need to be able to build this thing

而且還要用最簡單的科技

using simple manufacturing techniques and factories

及最簡單的工廠來製造這個東西

that don't cost us a fortune.

不要花很多錢

So about six years ago,

所以大約六年前

I started thinking about this problem.

我開始思索這個問題

And in order to adopt a fresh perspective,

為了要得到新的觀點

I sought inspiration from beyond the field of electricity storage.

我從蓄電學以外的地方尋求靈感

In fact, I looked to a technology

事實上我從一個跟蓄電或發電

that neither stores nor generates electricity,

一點都沒關聯的科技來看這件事

but instead consumes electricity,

這個科技反而還消耗

huge amounts of it.

大量電力

I'm talking about the production of aluminum.

我指的是煉鋁工業

The process was invented in 1886

煉鋁法是在1886年

by a couple of 22-year-olds --

由兩位22歲的人

Hall in the United States and Heroult in France.

美國的霍爾及法國的赫魯特所發明

And just a few short years following their discovery,

之後短短幾年

aluminum changed

鋁就從

from a precious metal costing as much as silver

跟銀一樣貴的貴金屬

to a common structural material.

變成再普通不過的結構材料

You're looking at the cell house of a modern aluminum smelter.

你現在看到的是一座現代煉鋁廠的電解車間

It's about 50 feet wide

約50呎寬

and recedes about half a mile --

延伸約半哩遠

row after row of cells

一排又一排的電解槽

that, inside, resemble Volta's battery,

裡面的結構就像伏特的電池

with three important differences.

但又有三個重要的不同點

Volta's battery works at room temperature.

伏特的電池在室溫下運作

It's fitted with solid electrodes

使用固體電極棒

and an electrolyte that's a solution of salt and water.

電解質為鹽及水組成的水溶液

The Hall-Heroult cell

而霍爾--赫魯特電解槽

operates at high temperature,

在高溫下運作

a temperature high enough

這個溫度高到

that the aluminum metal product is liquid.

可以讓鋁金屬變成液態

The electrolyte

而電解質

is not a solution of salt and water,

不是由水及鹽組成的水溶液

but rather salt that's melted.

而是熔化的鹽

It's this combination of liquid metal,

這種由液態金屬

molten salt and high temperature

熔鹽及高溫的組合

that allows us to send high current through this thing.

可以讓高電流通過這個電解槽

Today, we can produce virgin metal from ore

今天我們可以從礦砂直接生產鋁金屬

at a cost of less than 50 cents a pound.

每磅成本低於50分美元（約15元台幣）

That's the economic miracle

這就是現代電氣冶金術

of modern electrometallurgy.

創造的經濟奇蹟

It is this that caught and held my attention

也就是這項製程吸引了我的注意

to the point that I became obsessed with inventing a battery

到了著迷的地步 我一心一意要發明

that could capture this gigantic economy of scale.

這種具強大經濟效益的電池

And I did.

而我的確做到了

I made the battery all liquid --

我製造了全液態電池

liquid metals for both electrodes

兩端電極均為液態金屬

and a molten salt for the electrolyte.

使用熔鹽作電解質

I'll show you how.

現在就來看看過程

So I put low-density

我把低密度

liquid metal at the top,

液態金屬放在上端

put a high-density liquid metal at the bottom,

高密度的液態金屬放在底端

and molten salt in between.

兩者之間放熔鹽

So now,

問題來了

how to choose the metals?

要怎麼選金屬

For me, the design exercise

對我而言 設計這門功課

always begins here

永遠從這裡開始

with the periodic table,

就是拿出這張

enunciated by another professor,

由另一位有用的教授

Dimitri Mendeleyev.

門德列夫所發表的週期表

Everything we know

這世上的一切

is made of some combination

都由週期表上的元素

of what you see depicted here.

以不同的組態組合

And that includes our own bodies.

我們的身體也是如此

I recall the very moment one day

我還記得那天

when I was searching for a pair of metals

我在找一對金屬

that would meet the constraints

一對合乎

of earth abundance,

藴藏量大

different, opposite density

密度相反

and high mutual reactivity.

相互反應性高的條件

I felt the thrill of realization

當我知道我快要找到答案時

when I knew I'd come upon the answer.

我有一種恍然大悟的驚喜

Magnesium for the top layer.

鎂在頂層

And antimony

而銻

for the bottom layer.

放在底層

You know, I've got to tell you,

你知道嗎 我一定要告訴你

one of the greatest benefits of being a professor:

作教授的好處之一就是

colored chalk.

你可以用彩色粉筆

(Laughter)

（笑聲）

So to produce current,

為了製造電流

magnesium loses two electrons

鎂失去兩個電子

to become magnesium ion,

成為鎂離子

which then migrates across the electrolyte,

移動通過電解質

accepts two electrons from the antimony,

從銻那一端接受兩個電子

and then mixes with it to form an alloy.

然後與銻形成合金

The electrons go to work

電子是真正

in the real world out here,

產生電流的物質

powering our devices.

使我們的儀器有電

Now to charge the battery,

現在要使電池充電

we connect a source of electricity.

我們把電池接上電源

It could be something like a wind farm.

電源可以是風力發電廠

And then we reverse the current.

然後我們讓反應倒過來

And this forces magnesium to de-alloy

這使得鎂離開合金

and return to the upper electrode,

回到上端的電極

restoring the initial constitution of the battery.

使電池回到原來的組態

And the current passing between the electrodes

電流穿越兩極之間

generates enough heat to keep it at temperature.

產生足夠的熱能以維持溫度

It's pretty cool,

很酷吧

at least in theory.

至少理論上聽起來是如此

But does it really work?

但是要怎麼實際運作呢

So what to do next?

所以接下來該做什麼

We go to the laboratory.

我們去作實驗

Now do I hire seasoned professionals?

我聘請了資深的研究人員嗎

No, I hire a student

沒有 我找了一個學生

and mentor him,

而且親自指導他

teach him how to think about the problem,

教他如何從我的觀點

to see it from my perspective

來看這個問題

and then turn him loose.

然後就放牛吃草

This is that student, David Bradwell,

這就是那位學生 大衛布萊德威

who, in this image,

他在這張相片裡

appears to be wondering if this thing will ever work.

看起來不太相信這個東西能成功

What I didn't tell David at the time

我那時沒有告訴大衛

was I myself wasn't convinced it would work.

就是我自己也不太相信這能成功

But David's young and he's smart

但是大衛年青有為

and he wants a Ph.D.,

而且他想拿博士

and he proceeds to build --

他開始

(Laughter)

（笑聲）

He proceeds to build

他開始製作

the first ever liquid metal battery

第一個用這個化學理論為基礎

of this chemistry.

所創造的液態金屬電池

And based on David's initial promising results,

大衛的結果看起來前景大有可為

which were paid

本來這項實驗的原始經費

with seed funds at MIT,

是由麻省理工的種子創投基金所支付

I was able to attract major research funding

我因此可以藉著這個結果吸引更多的

from the private sector

私人企業及聯邦政府

and the federal government.

來投資這項計劃

And that allowed me to expand my group to 20 people,

這也讓我能擴充研究團隊至20人

a mix of graduate students, post-docs

包括研究生 博士後研究

and even some undergraduates.

甚至還有一些大學生

And I was able to attract really, really good people,

我可以吸引到很棒很棒的人

people who share my passion

這些人跟我一樣

for science and service to society,

對科學及對服務大眾充滿熱情

not science and service for career building.

這些人唸科學不是為了發展自己的事業

And if you ask these people

如果你問這些人

why they work on liquid metal battery,

為什麼要研究液態金屬電池

their answer would hearken back

他們會借用

to President Kennedy's remarks

甘乃迪總統在1962年

at Rice University in 1962

對萊斯大學的演講來回答

when he said -- and I'm taking liberties here --

甘乃迪說 容我篡改一下

"We choose to work on grid-level storage,

我們選擇做這項電網級大型儲電計畫

not because it is easy,

不是因為它很簡單

but because it is hard."

而是因為它很艱難

(Applause)

（掌聲）

So this is the evolution of the liquid metal battery.

以下是液態金屬電池的演進過程

We start here with our workhorse one watt-hour cell.

我們從這個一瓦時的電池開始

I called it the shotglass.

我稱它為小酒杯

We've operated over 400 of these,

我們把400個小酒杯放在一起運轉

perfecting their performance with a plurality of chemistries --

充分利用化學的多元化來找最好的反應組合

not just magnesium and antimony.

而不是只限於使用鎂及銻

Along the way we scaled up to the 20 watt-hour cell.

然後我們造了一個20瓦時的電池

I call it the hockey puck.

我稱之為冰上曲棍球

And we got the same remarkable results.

我們得到的結果一樣驚人

And then it was onto the saucer.

然後是這個茶盤

That's 200 watt-hours.

200瓦時的電力

The technology was proving itself

這個科技本身證明了

to be robust and scalable.

這個電池堅固耐用及可擴展性

But the pace wasn't fast enough for us.

但是我們對發展的速度不滿意

So a year and a half ago,

所以一年半前

David and I,

大衛和我

along with another research staff-member,

以及其他研究人員

formed a company

成立了一間公司

to accelerate the rate of progress

來加速製造過程

and the race to manufacture product.

加速產品商業化

So today at LMBC,

所以現在液態金屬電池公司

we're building cells 16 inches in diameter

製造直徑16英寸大

with a capacity of one kilowatt-hour --

儲電容量一千瓦時的電池

1,000 times the capacity

是那個原始小酒杯

of that initial shotglass cell.

的一千倍

We call that the pizza.

我們叫它比薩

And then we've got a four kilowatt-hour cell on the horizon.

現在四千瓦時的電池快要造好了

It's going to be 36 inches in diameter.

它的直徑將達36吋

We call that the bistro table,

我們說它是個小餐桌

but it's not ready yet for prime-time viewing.

不過這還不能端上檯面來看

And one variant of the technology

這項科技的變化之一

has us stacking these bistro tabletops into modules,

是把這些小餐桌堆成模組

aggregating the modules into a giant battery

然後將這些模組聚合成一個巨大的電池

that fits in a 40-foot shipping container

可以塞在一個40呎的貨櫃裡

for placement in the field.

運到發電廠

And this has a nameplate capacity of two megawatt-hours --

這個大電池的儲電容量為二兆瓦小時

two million watt-hours.

也就是兩百萬瓦時

That's enough energy

這樣的電力

to meet the daily electrical needs

足以維持200個美國家庭

of 200 American households.

每日所需

So here you have it, grid-level storage:

所以我們有了電網級大型儲電系統

silent, emissions-free,

安靜 零排汙

no moving parts,

沒有會動的機件

remotely controlled,

還可以遙控

designed to the market price point

以目前的電價就可使之運轉

without subsidy.

不需政府補助

So what have we learned from all this?

所以我們從中學到甚麼？

(Applause)

（掌聲）

So what have we learned from all this?

所以我們從中學到甚麼？

Let me share with you

讓我與在座各位分享

some of the surprises, the heterodoxies.

一些意外發現 與公認事實大庭相逕

They lie beyond the visible.

這些事實並不是那麼顯而易見

Temperature:

在溫度方面

Conventional wisdom says set it low,

一般都認為反應要設在低溫

at or near room temperature,

最好是在室溫下

and then install a control system to keep it there.

然後要架一個系統來控溫

Avoid thermal runaway.

不要讓溫度失控

Liquid metal battery is designed to operate at elevated temperature

但是液態金屬電池是設計在高溫下運作

with minimum regulation.

沒有甚麼溫度限制條件

Our battery can handle the very high temperature rises

這個電池可以忍受因突波電流

that come from current surges.

所產生的急劇增溫現象

Scaling: Conventional wisdom says

在規模方面 一般都認為

reduce cost by producing many.

要大量生產來減低成品

Liquid metal battery is designed to reduce cost

但液態金屬電池減低成本的方法

by producing fewer, but they'll be larger.

是少量生產但產品本身很大

And finally, human resources:

最後在人力資源方面

Conventional wisdom says

大家都說

hire battery experts,

你要聘請電池專家

seasoned professionals,

資深的教授來參與

who can draw upon their vast experience and knowledge.

所以你可以借鑒他們豐富的經驗和知識

To develop liquid metal battery,

但在發展液態金屬電池這個計劃上

I hired students and post-docs and mentored them.

我找了學生及博士後研究員 還親自指導他們

In a battery,

在製作電池時

I strive to maximize electrical potential;

我絞盡腦汁讓電池的電力發展到極致

when mentoring,

在指導學生時

I strive to maximize human potential.

我則絞盡腦汁讓他們的潛力發展到極致

So you see,

所以你看

the liquid metal battery story

發展液態金屬電池這件事

is more than an account

不是只有

of inventing technology,

發明新科技而已

it's a blueprint

這還是個藍圖

for inventing inventors, full-spectrum.

讓我們全方位培養發明家

(Applause)

（掌聲）