TEDxWarwick
David MacKay: A reality check on renewables
大衛麥凱：務實探討再生能源。
Filmed:
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再生能源廠需要耗費多少土地興建，才能有足夠的產能以應付像英國這種國家所需？全國規模。這場務實的演說中，大衛麥凱以基本數學為導覽向我們解說，選擇永續能源有哪些令人憂慮的限制，並解釋為何我們仍須以其為目標。 (Filmed at TEDxWarwick.)
David MacKay - Professor
As an information theorist and computer scientist, David MacKay uses hard math to assess our renewable energy options. Full bio
As an information theorist and computer scientist, David MacKay uses hard math to assess our renewable energy options. Full bio
Double-click the English transcript below to play the video.
00:16
When the Industrial Revolution started,
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工業革命開始時，
00:18
the amount of carbon sitting underneath
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埋藏在英國地下的
00:20
Britain in the form of coal was as big as the amount
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煤礦蘊藏量相等於
00:24
of carbon sitting under Saudi Arabia in the form of oil,
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沙烏地阿拉伯的石油蘊藏量，
00:29
and this carbon powered the Industrial Revolution,
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這些煤炭推動了工業革命，
00:31
it put the "Great" in Great Britain,
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讓大不列顛夠格稱為「大」國
00:33
and led to Britain's temporary world domination.
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也讓英國短暫地稱霸世界。
00:37
And then, in 1918, coal production in Britain peaked,
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時間來到1918年，英國的煤產量升至頂點，
00:42
and has declined ever since.
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此後便一蹶不振。
00:44
In due course, Britain started using oil and gas
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其間，英國開始使用北海的
00:47
from the North Sea, and in the year 2000,
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石油和石油氣，而2000年時，
00:50
oil and gas production from the North Sea
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北海石油與石油氣的產量
00:52
also peaked, and they're now on the decline.
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也達到了顛峰，現在正在衰退。
00:57
These observations about the finiteness of
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觀察這些有限的、容易開採的、
01:00
easily accessible, local, secure fossil fuels,
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本土的、安全的化石燃料，
01:04
this is a motivation for saying, "Well, what's next?
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讓我們有股衝動要問：「接下來會怎樣？
01:08
What is life after fossil fuels going to be like?
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化石燃料用盡後，生活會變成怎樣呢？
01:10
Shouldn't we be thinking hard about
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我們不是應該殫思竭慮
01:12
how to get off fossil fuels?"
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擺脫化石燃料的方法嗎？」
01:14
Another motivation, of course, is climate change.
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另一個動機，當然是氣候的轉變。
01:18
And when people talk about life after fossil fuels
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而人們論及化石燃料耗盡後的生活，
01:20
and climate change action, I think there's a lot of
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與氣候變化的補救措施時，我認為其中有很多誤解，
01:23
fluff, a lot of greenwash, a lot of misleading advertising,
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很多表裡不一的廠商，很多誤導的廣告，
01:27
and I feel a duty as a physicist to try to
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身為物理學家，我有責任
01:30
guide people around the claptrap and help people
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指引群眾避開譁眾取寵的話術陷阱，
01:33
understand the actions that really make a difference
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協助群眾瞭解那些能實質改變現狀的行動，
01:35
and to focus on ideas that do add up.
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並集中焦點於合情理的想法。
01:40
Let me illustrate this with what physicists call
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讓我以物理學家所謂的
01:43
a back-of-envelope calculation.
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「信封背面的算式」來闡述此事。
01:46
We love back-of-envelope calculations.
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我們喜歡「信封背面的算式」。
01:47
You ask a question, you write down some numbers,
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你提出一條問題，你寫下一些數字，
01:49
and you get yourself an answer.
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然後你自己找答案。
01:50
It may not be very accurate, but it may make you say,
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這樣未必能作到精準，但可能會讓你發出沉吟之聲：
01:53
"Hmm."
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「嗯。」
01:54
So here's a question: Imagine if
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那麼問題來了：想像一下，如果
01:56
we said, "Oh yes, we can get off fossil fuels.
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我們說：「是啊，我們能擺脫化石燃料。
01:59
We'll use biofuels. Problem solved.
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我們會使用生化燃料。問題解決。
02:00
Transport, we don't need oil anymore."
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運輸方面，我們不再需要石油了。」
02:02
Well, what if we grew the biofuels for a road
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好，我們用在路邊種草叢
02:09
on the grass verge at the edge of the road?
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來培植生化原油如何？
02:13
How wide would the verge have to be for that to work out?
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需要多少面積的草叢才能成事呢？
02:17
Okay, so let's put in some numbers.
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好，我們來代入一些數字。
02:18
Let's have our cars go at 60 miles per hour.
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假設我們的汽車以每小時60英哩行駛，
02:21
Let's say they do 30 miles per gallon.
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假設這些車子每加侖可以行駛30英哩。
02:23
That's the European average for new cars.
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那是歐洲新車款的平均數。
02:26
Let's say the productivity of biofuel plantations
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就是說生化燃料製造廠的產量
02:28
is 1,200 litres of biofuel per hectare per year.
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是每年每平方頃1,200升的生化燃料。
02:32
That's true of European biofuels.
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這是歐洲生化燃料界的現況。
02:34
And let's imagine the cars are spaced 80 meters
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再假設每輛汽車的間距是80米，
02:37
apart from each other, and they're just perpetually going
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而且每輛車都是恆動地
02:39
along this road.
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行駛於道路。
02:40
The length of the road doesn't matter, because the longer
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道路的長度無所謂，因為道路愈長，
02:42
the road, the more biofuel plantation we've got.
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我們的生化燃料廠就越多。
02:45
What do we do with these numbers?
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我們怎樣用這些數字運算呢？
02:46
Well, you take the first number, and you divide by
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好，你們用第一個數字，
02:48
the other three, and you get eight kilometers.
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然後用餘下的三個數字除之，結果是八公里。
02:50
And that's the answer.
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那就是答案。
02:51
That's how wide the plantation would have to be,
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那就是各廠房間該有的距離，
02:54
given these assumptions.
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基於以上的假設。
02:56
And maybe that makes you say, "Hmm.
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對此，你可能會說：「嗯，
02:59
Maybe this isn't going to be quite so easy."
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這件事好像沒那麼容易。」
03:03
And it might make you think, perhaps there's an issue
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你也許還會想，關於土地面積
03:07
to do with areas, and in this talk,
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可能有某些爭議，而今天這次演說，
03:09
I'd like to talk about land areas, and ask,
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我想談談土地面積，還要問問各位，
03:12
is there an issue about areas? The answer is going to be
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土地面積是否有爭議？答案是有，
03:16
yes but it depends which country you are in.
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但需取決於你居住的國家。
03:18
So let's start in the United Kingdom,
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所以我們就英國開始，
03:21
since that's where we are today.
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因為那是我們現在住的地方。
03:23
The energy consumption of the United Kingdom,
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英國的能源消耗，
03:25
the total energy consumption, not just transport, but everything,
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能源消耗總值，不只是運輸，而是囊括全部，
03:29
I like to quantify it in light bulbs.
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我喜歡以燈泡來量化這數字。
03:31
It's as if we've all got 125 light bulbs on all the time,
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那就像我們每個人全天開着125顆電燈泡，
03:35
125 kilowatt-hours per day per person
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每人每天125千瓦，
03:39
is the energy consumption of the U.K.
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這就是英國的能源消耗量。
03:42
So there's 40 light bulbs' worth for transport,
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所以共有40個電燈泡可用於交通，
03:45
40 light bulbs' worth for heating,
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40個電燈泡可用於暖氣。
03:46
and 40 light bulbs' worth for making electricity,
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40個電燈泡可用於發電，
03:49
and other things are relatively small
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比起那三條「大魚」，
03:51
compared to those three big fish.
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其他的相對來說小得多。
03:54
It's actually a bigger footprint if we take into account
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其實，如果我們將進口產品的實際耗能也計算進去，
03:56
the embodied energy in the stuff we import
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廠房所需的面積會更大
03:58
into our country as well, and 90 percent of this energy today
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而今天這些能源有百分之九十
04:03
still comes from fossil fuels, and 10 percent only
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仍來自化石燃料，只有百分之十
04:06
from other, greener -- possibly greener -- sources
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來自其他較環保的──可能較環保的──資源，
04:08
like nuclear power and renewables.
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如核能和再生能源。
04:11
So,
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因此，
04:13
that's the U.K., and the population density of the U.K.
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這就是英國的情況，而英國人口密度
04:16
is 250 people per square kilometer,
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是每平方公里250人，
04:19
and I'm now going to show you other countries
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現在我要讓你們看看其他國家
04:21
by these same two measures.
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以相同兩種計算方式的結果。
04:22
On the vertical axis, I'm going to show you
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在垂直軸，我會指出
04:24
how much light bulbs -- what our energy consumption
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有多少電燈泡──也就是我們的個人能源消耗量，
04:27
per person is, and we're at 125 light bulbs per person,
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我們的個人消耗量是125個電燈泡，
04:30
and that little blue dot there is showing you the land area
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而那個小藍點表示的是
04:33
of the United Kingdom,
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英國的土地面積，
04:36
and the population density is on the horizontal axis,
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而人口密度就在橫線軸，
04:38
and we're 250 people per square kilometer.
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我們每平方公里有250人。
04:41
Let's add European countries in blue,
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然後我們以藍色標示加入的歐洲國家，
04:44
and you can see there's quite a variety.
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你們會發現差異相當明顯。
04:46
I should emphasize, both of these axes
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我必須強調，這兩條軸線
04:49
are logarithmic. As you go from one gray bar
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都是對數。你們從這條灰線
04:51
to the next gray bar you're going up a factor of 10.
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移到另一條灰線時，差異是10的平方。
04:54
Next, let's add Asia in red,
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再來，我們用紅色標示加入的亞洲，
04:57
the Middle East and North Africa in green,
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以綠色標示中東和北非，
05:01
sub-Saharan Africa in blue,
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以藍色標示次撒哈拉非洲，
05:04
black is South America,
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黑色是南美洲，
05:07
purple is Central America,
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紫色是中美洲，
05:10
and then in pukey-yellow, we have North America,
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然後是噁心的黃色，北美洲、
05:13
Australia and New Zealand.
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澳洲和新西蘭在此。
05:16
And you can see the great diversity of population densities
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你們可看到，這些地區的人口密度
05:18
and of per capita consumptions.
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以及人均消耗量的差異極大。
05:22
Countries are different from each other.
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每國家各有不同之處。
05:24
Top left, we have Canada and Australia, with enormous
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左上方是加拿大和澳洲，土地面積龐大，
05:26
land areas, very high per capita consumption,
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人均消耗量也極高，
05:29
200 or 300 light bulbs per person,
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每人200 至300個電燈泡，
05:32
and very low population densities.
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而人口密度非常低。
05:36
Top right, Bahrain has the same energy consumption
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右上方的巴林的人平均能量消耗
05:38
per person, roughly, as Canada,
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幾乎和加拿大ㄧ樣。
05:41
over 300 light bulbs per person,
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每人超過300個電燈泡，
05:43
but their population density is a factor of 300 times greater,
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但是這國家的人口密度高了300倍，
05:46
1,000 people per square kilometer.
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每平方公里1,000人。
05:48
Bottom right, Bangladesh has the same population density
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右下方，孟加拉和巴林人口密度相若，
05:51
as Bahrain but consumes 100 times less per person.
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但人平均消耗量只有百分之ㄧ。
05:56
Bottom left, well, there's no one.
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左下方，嗯，罕無人煙。
05:59
But there used to be a whole load of people.
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但這裏從前有一大群人。
06:01
Here's another message from this diagram.
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這張圖表還蘊藏了另一則訊息。
06:03
I've added on little blue tails behind Sudan, Libya,
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我在蘇丹、利比亞、中國、印度、孟加拉
06:07
China, India, Bangladesh.
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後頭加上了藍色細線。
06:08
That's 15 years of progress.
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那是15年來的進展。
06:10
Where were they 15 years ago, and where are they now?
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15年前他們在何方？而今天他們又在哪兒呢？
06:13
And the message is, most countries are going to the right,
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另一個訊息是，大部分國家都在向右移，
06:15
and they're going up,
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還會向上移。
06:16
up and to the right -- bigger population density
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上右方，人口密度更高
06:19
and higher per capita consumption.
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人均消耗量也更高。
06:21
So, we may be off in the top right-hand corner,
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所以，也許我們還沒到最右邊的上面，
06:23
slightly unusual, the United Kingdom accompanied by
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有點奇怪的是，英國之後接著
06:26
Germany, Japan, South Korea, the Netherlands,
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德國、日本、南韓、荷蘭，
06:29
and a bunch of other slightly odd countries,
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和一連串有點古怪的國家，
06:31
but many other countries are coming up
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不過很多其他國家正向右上方移動，
06:34
and to the right to come and join us,
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準備加入我們。
06:36
so we're a picture, if you like, of what the future energy
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所以如果要用比喻，我們像是一種未來的寫照，
06:39
consumption might be looking like in other countries too.
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那些國家也可能會步上我們的後塵。
06:44
And I've also added in this diagram now some pink lines
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現在我在圖表上又加了幾條粉紅線，
06:47
that go down and to the right.
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由左上向右下。
06:49
Those are lines of equal power consumption
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用這幾條線劃分單位土地耗電量相同的區域，
06:51
per unit area, which I measure in watts per square meter.
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計算單位是每平方米消耗的瓦數。
06:55
So, for example, the middle line there,
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所以，舉例來說，中間線那條線，
06:57
0.1 watts per square meter, is the energy consumption
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每平方米0.1瓦，是沙地阿拉伯、挪威、
07:00
per unit area of Saudi Arabia, Norway, Mexico in purple,
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墨西哥的單位土地能源消耗，以紫色顯示，
07:05
and Bangladesh 15 years ago,
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和15年前的孟加拉，
07:08
and half of the world's population lives in countries
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而世界人口有一半都住在
07:11
that are already above that line.
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這條線右上方的國家。
07:15
The United Kingdom is consuming 1.25
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英國目前的消耗量是
07:18
watts per square meter.
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每平方米1.25瓦。
07:20
So's Germany, and Japan is consuming a bit more.
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德國亦然，而日本的消耗量稍高。
07:25
So, let's now
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好，我們現在來
07:27
say why this is relevant. Why is it relevant?
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說說為何這件事意義重大，為何意義重大？
07:30
Well, we can measure renewables in the same units
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我們用相同面積使用再生能源來計算，
07:33
and other forms of power production in the same units,
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或是相同面積使用其他形式製造的能源。
07:36
and renewables is one of the leading ideas for
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我們使用的能源有90%要依賴石化燃料，
07:39
how we could get off our 90 percent fossil fuel habit.
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使用再生能源是劃時代的解決方案之ㄧ。
07:43
So here come some renewables.
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我們現在有幾種再生能源。
07:44
Energy crops deliver half a watt per square meter
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歐洲地區的農產能源
07:47
in European climates.
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每平方米可提供0.5瓦。
07:50
What does that mean? And you might have anticipated
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這代表什麼？你們可能猜到答案了，
07:52
that result, given what I told you about the biofuel plantation
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基於我剛剛對你們說過的，
07:55
a moment ago.
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生化燃料製造廠。
07:56
Well, we consume 1.25 watts per square meter.
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好，我們每平方米消耗1.25瓦。
07:59
What this means is, even if you covered
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這代表即使我們將能源農作物
08:01
the whole of the United Kingdom with energy crops,
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種滿整個大英帝國，
08:04
you couldn't match today's energy consumption.
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也無法滿足現今的能源消耗量。
08:08
Wind power produces a bit more,
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風力能源的產值稍高，
08:10
2.5 watts per square meter, but that's only twice as big
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每平方米2.5瓦，但那也不過比每平方米1.25瓦
08:13
as 1.25 watts per square meter,
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多ㄧ倍而已。
08:16
so that means if you wanted literally to produce total
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那表示，如果我們要用風力發電來
08:20
energy consumption in all forms on average from
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供應全國所有的能源消耗，
08:22
wind farms, you need wind farms half the area of the U.K.
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我們需要的風力發電廠將占據半個英國。
08:27
I've got data to back up all these assertions, by the way.
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附帶一提，所有的假設我都有數據支持，
08:31
Next, let's look at solar power.
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其次，讓我們看看太陽能。
08:33
Solar panels, when you put them on a roof,
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太陽能板，在英國，我們在屋頂設置太陽能板時，
08:36
deliver about 20 watts per square meter in England.
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每平方米大約能產生20瓦。
08:41
If you really want to get a lot from solar panels,
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如果我們真的想大量使用太陽能板發電，
08:43
you need to adopt the traditional Bavarian farming method
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我們得採用傳統的巴伐利亞耕作法，
08:46
where you leap off the roof and coat the countryside
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鋪完屋頂後我們要跳下來，把郊野農地也鋪上
08:49
with solar panels too.
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太陽能板。
08:51
Solar parks, because of the gaps between the panels,
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太陽能電廠，因為板子之間有空隙，
08:53
deliver less. They deliver about 5 watts
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產能較少。太陽能產生的能量
08:55
per square meter of land area.
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大約是每平方米的土地 5 瓦。
08:57
And here's a solar park in Vermont with real data
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這是佛蒙特洲ㄧ間太陽能發電廠的實際數據，
09:00
delivering 4.2 watts per square meter.
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每平方米4.2瓦的產能。
09:03
Remember where we are, 1.25 watts per square meter,
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記着我們住哪兒，每平方米1.25瓦，
09:06
wind farms 2.5, solar parks about five.
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風力發電廠2.5瓦，太陽能發電廠大約5瓦。
09:10
So, whatever, whichever of those renewables you pick,
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所以，無論如何，無論我們選擇了哪種再生能源，
09:14
the message is, whatever mix of those renewables
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我們的啟發是，無論我們如何搭配使用這些再生能源，
09:16
you're using, if you want to power the U.K. on them,
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如果英國想依賴這些再生能源，
09:19
you're going to need to cover something like
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這些再生能源的裝置
09:21
20 percent or 25 percent of the country
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大約會覆蓋英國國土的
09:24
with those renewables.
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百分之 20 或 25。
09:26
And I'm not saying that's a bad idea.
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我不是在批評這個點子。
09:28
We just need to understand the numbers.
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我們必須了解這些數據。
09:29
I'm absolutely not anti-renewables. I love renewables.
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我絕對不是反對再生能源。我愛再生能源。
09:32
But I'm also pro-arithmetic. (Laughter)
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但我也喜歡算術。(眾笑)
09:36
Concentrating solar power in deserts delivers
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將太陽能發電裝置集中於沙漠，
09:39
larger powers per unit area, because you don't have
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產生的能量較高，因為這樣不會有
09:41
the problem of clouds,
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雲層遮蔽的問題，
09:42
and so this facility delivers 14 watts per square meter,
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所以這種設施的產能是每平方米14瓦，
09:45
this one 10 watts per square meter,
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這個是每平方米10瓦，
09:47
and this one in Spain 5 watts per square meter.
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西班牙的這個是每平方米5瓦。
09:50
Being generous to concentrating solar power,
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以太陽能做為發電主力，
09:52
I think it's perfect credible it could deliver 20 watts
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我認為每平方米20瓦的電力
09:55
per square meter. So that's nice.
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絕對沒問題，所以這是可行的。
09:57
Of course, Britain doesn't have any deserts.
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當然，英國沒有任何沙漠。
10:00
Yet. (Laughter)
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至少目前還沒有。(眾笑)
10:03
So here's a summary so far.
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這是至此為止的總結
10:06
All renewables, much as I love them, are diffuse.
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所有這些再生能源，和我對它們的愛一樣，到處都是。
10:09
They all have a small power per unit area,
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所有再生能源每單位面積的產能都不高，
10:11
and we have to live with that fact.
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我們要接受這項事實。
10:13
And that means, if you do want renewables
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那表示，今天如果我們真的想用再生能源
10:17
to make a substantial difference for a country like
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來大幅改變像英國這種國家的
10:19
the United Kingdom on the scale of today's consumption,
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能源消耗量，
10:23
you need to be imagining renewable facilities
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我們設想的再生能源設備的規模
10:25
that are country-sized, not the entire country
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是國家級的，不是蓋滿整個國家，
10:28
but a fraction of the country, a substantial fraction.
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而是國土的某個區域，可觀的區域。
10:33
There are other options for generating power as well
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還有其他方式能產生能源，
10:35
which don't involve fossil fuels.
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其中不包括化石燃料。
10:37
So there's nuclear power, and on this Ordnance
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那就是核能，而這張地形測量圖上，
10:40
Survey map, you can see there's a Sizewell B
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我們可以看到賽滋威爾 B 核電廠
10:42
inside a blue square kilometer.
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位於ㄧ片方形的藍色中。
10:44
That's one gigawatt in a square kilometer,
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意思是一平方公里 10 億瓦，
10:46
which works out to 1,000 watts per square meter.
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產量達到每平方米1,000瓦。
10:49
So by this particular metric, nuclear power
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由於這個度量的產值那麼高，核能
10:51
isn't as intrusive as renewables.
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不像再生能源那麼佔空間。
10:57
Of course, other metrics matter too, and nuclear power
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當然，其他的度量也很重要，而核能
10:59
has all sorts of popularity problems.
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有許多公共安全方面的問題。
11:02
But the same goes for renewables as well.
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但再生能源亦然。
11:04
Here's a photograph of a consultation exercise in full swing
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這是一場激進的諮詢行動現場照片，
11:06
in the little town of Penicuik just outside Edinburgh,
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地點是愛丁堡市郊的ㄧ座小鎮，潘尼庫克，
11:10
and you can see the children of Penicuik celebrating
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你們可以看到，潘尼庫克的小孩正對著
11:12
the burning of the effigy of the windmill.
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燃燒的風車高聲歡呼。
11:14
So people are anti-everything, and we've got to keep
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所以我們無法滿足所有人，我們必須
11:19
all the options on the table.
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秀出所有的選擇。
11:22
What can a country like the U.K. do on the supply side?
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像英國這種國家能提供甚麼選擇呢？
11:25
Well, the options are, I'd say, these three:
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其實，在我看來，選擇有三：
11:28
power renewables, and recognizing that they need to be
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再生能源，並承認這個產業需要整個國家
11:31
close to country-sized; other people's renewables,
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傾力支持；其他國家的再生能源，
11:34
so we could go back and talk very politely to the people
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我們能放下身段去找圖表左上方的
11:37
in the top left-hand side of the diagram and say,
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那些國家，非常有禮貌地說：
11:39
"Uh, we don't want renewables in our backyard,
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「嗯，我們不希望再生能源設備蓋在我們的後園，
11:41
but, um, please could we put them in yours instead?"
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然後，嗯，請容許我們把這些設備蓋在你那裏好嗎？
11:45
And that's a serious option.
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那個選擇需要嚴肅看待。
11:46
It's a way for the world to handle this issue.
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這是全世界解決這種議題的方法之ㄧ。
11:50
So countries like Australia, Russia, Libya, Kazakhstan,
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像是澳洲、俄羅斯、利比亞、哈薩克這些國家
11:54
could be our best friends for renewable production.
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可能是我們再生能源業最好的朋友。
11:59
And a third option is nuclear power.
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第三個選擇是核能。
12:01
So that's some supply side options.
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這幾個可供人民選擇。
12:03
In addition to the supply levers that we can push,
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除了推行方案供人民選擇之外，
12:06
and remember, we need large amounts,
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我們要記住，我們需要大量的再生能源，
12:08
because at the moment,
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因為此時此刻，
12:09
we get 90 percent of our energy from fossil fuels.
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我們有百分之九十的能源來自化石燃料。
12:12
In addition to those levers, we could talk about other ways
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除了那些手段之外，我們可以討論出其他方式
12:14
of solving this issue, namely, we could reduce demand,
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來解決這問題，也就是，我們能降低需求，
12:17
and that means reducing population
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而那表示減少人口
12:19
— I'm not sure how to do that —
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─ 我不確定該怎麼做 ─
12:21
or reducing per capita consumption.
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或減少人均消耗。
12:25
So let's talk about three more big levers
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所以我們來討論三個規模更大的手段，
12:27
that could really help on the consumption side.
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對於減少消耗有真正的幫助。
12:29
First, transport. Here are the physics principles that tell you
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首先是運輸。這裡的幾條物理定律告訴你
12:32
how to reduce the energy consumption of transport,
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如何減低運輸過程的能源消耗，
12:35
and people often say, "Oh, yes, technology can answer everything.
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人們通常會說：「對啊，科技能回答任何問題。
12:37
We can make vehicles that are a hundred times more
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我們能製造效率高 100 倍
12:39
efficient." And that's almost true. Let me show you.
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的汽車。」這就快要成真了。我讓你們看看，
12:42
The energy consumption of this typical tank here
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這款典型汽車的能源消耗
12:45
is 80 kilowatt-hours per hundred person kilometers.
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是每百人每公里每小時 80 千瓦。
12:48
That's the average European car.
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那是一般的歐洲車款。
12:53
Eighty kilowatt-hours. Can we make something a hundred times
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每小時 80 千瓦。我們能否利用我剛才列舉的
12:55
better by applying those physics principles I just listed?
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那些物理定律來製造效率高一百倍的東西嗎？
12:57
Yes. Here it is. It's the bicycle. It's 80 times better in energy
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可以。就是這個。那是款單車。這款單車的效率高了 80 倍，
13:02
consumption, and it's powered by biofuel, by Weetabix.
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而且是生化燃料推動的，提煉自維多麥。
13:05
(Laughter)
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(眾笑)
13:07
And there are other options in between, because maybe
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其中還有其它選擇，因為車裡的小姐
13:09
the lady in the tank would say, "No, no, no,
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可能會說：「不行，不行，
13:11
that's a lifestyle change. Don't change my lifestyle, please."
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那是生活形式的改變，請不要改變我的生活方式。」
13:13
So, well, we could persuade her to get into a train,
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好，沒關係，我們可以說服她搭火車，
13:16
and that's still a lot more efficient than a car,
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這還是比開車遠遠有效率，
13:18
but that might be a lifestyle change,
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不過這可能需要改變生活方式，
13:19
or there's the eco-car, top-left.
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1734
或是選擇環保汽車，在左上方。
13:21
It comfortably accommodates one teenager
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1994
車內的空間容納ㄧ位年輕人綽綽有餘，
13:23
and it's shorter than a traffic cone,
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高度比交通錐還矮，
13:24
and it's almost as efficient as a bicycle
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車子的效率幾乎和單車一樣，
13:27
as long as you drive it at 15 miles per hour.
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前提是你以每小時15英哩行駛。
13:30
In between, perhaps some more realistic options
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這些選擇中，也許還有更實際的手段
13:32
on this lever, transport lever, are electric vehicles,
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改善運輸，可用電動汽車，
13:35
so electric bikes and electric cars in the middle,
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所以選項中的電動單車和電動汽車
13:38
perhaps four times as energy efficient
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它們的效率也許能比汽油驅動的
13:40
as the standard petrol-powered tank.
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傳統車輛高出四倍。
13:44
Next, there's the heating lever.
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再來，還要解決暖氣。
13:46
Heating is a third of our energy consumption in Britain,
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我們的暖氣設備消耗了英國三分之一的能源，
13:50
and quite a lot of that is going into homes
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有許多是自宅暖氣。
13:51
and other buildings doing space heating and water heating.
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而其他的用於大樓的室溫加熱和熱水。
13:55
So here's a typical crappy British house.
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這是一間典型的英式破屋。
13:57
It's my house, with the Ferrari out front.
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這是我家，屋外停的是法拉利。
14:01
What can we do to it?
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我們該怎樣做呢？
14:02
Well, the laws of physics are written up there,
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嗯，物理定律寫在上面，
14:05
which describe what -- how the power consumption
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這些定律說明了 ── 你們能控制甚麼東西來
14:11
for heating is driven by the things you can control.
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影響加熱消耗的能量。
14:13
The things you can control are the temperature difference
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你們能控制的是溫度差異，
14:16
between the inside and the outside, and there's this
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2024
屋內和屋外的，另外還有這種
14:18
remarkable technology called a thermostat.
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特別的科技，叫恒溫器。
14:20
You grasp it, you rotate it to the left,
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1918
握着它，向左邊轉，
14:22
and your energy consumption in the home will decrease.
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你們家的能源消耗會減少。
14:24
I've tried it. It works. Some people call it a lifestyle change.
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我試過。真的有用。有些人稱之為生活方式的改變。
14:28
You can also get the fluff men in to reduce the leakiness
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你們可以請清洗管道的人過來，察看大樓的管線有沒有破損
14:32
of your building -- put fluff in the walls, fluff in the roof,
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1920
── 將絨毛靠在牆上，將絨毛放在屋頂
14:34
and a new front door and so forth,
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還有新裝好的前門，以此類推，
14:38
and the sad truth is, this will save you money.
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令人傷心的事實是，這樣能幫你們省錢。
14:41
That's not sad, that's good, but the sad truth is, it'll only
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這不傷心，這是好事，令人傷心的事實是，這樣
14:44
get about 25 percent of the leakiness of your building,
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只能減少你們家大樓約四分之一的外洩量。
14:47
if you do these things, which are good ideas.
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這些都是好主意，如果你們願意執行。
14:49
If you really want to get a bit closer to Swedish
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如果你們真的希望這種破房子
14:52
building standards with a crappy house like this,
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能更接近瑞典的建築標準，
14:55
you need to be putting external insulation on the building
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你們要在建築物外牆鋪設絕緣體，
14:58
as shown by this block of flats in London.
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正如這棟倫敦的大樓。
15:02
You can also deliver heat more efficiently using heat pumps
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你們還能用熱力泵來大幅提升加熱效率，
15:05
which use a smaller bit of high grade energy like electricity
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那就是少用點像電力這種的高階能源，
15:08
to move heat from your garden into your house.
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將熱能由你們的後園轉移到屋內。
15:12
The third demand side option I want to talk about,
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我想說的第三個選擇替代方案，
15:14
the third way to reduce energy consumption is,
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第三個減少能源消耗的方法是，
15:16
read your meters.
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注意你們的電表。
15:18
And people talk a lot about smart meters,
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大家常常提到智能量錶，
15:19
but you can do it yourself.
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不過你們可以自己來。
15:20
Use your own eyes and be smart, read your meter,
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用你們眼睛，放聰明一點，注意你們的電錶，
15:24
and if you're anything like me, it'll change your life.
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如果你們跟著我做，能改變自己的生活。
15:26
Here's a graph I made.
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這是我製作的圖表。
15:28
I was writing a book about sustainable energy,
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我正在寫ㄧ本有關永續能源的書，
15:30
and a friend asked me, "Well how much energy do you use
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有個朋友問我：「你在家會用多少能源？」
15:33
at home?" And I was embarrassed. I didn't actually know.
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我尷尬不已。我自己也不太清楚。
15:35
And so I started reading the meter every week,
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所以我開始每星期察看電錶，
15:37
and the old meter readings are shown
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這張圖表的上半部是
15:39
in the top half of the graph, and then 2007
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就是電表的度數，然後最底下的綠色數字
15:42
is shown in green at the bottom, and that was when
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是 2007 年的度數，我從那時開始
15:44
I was reading the meter every week, and my life changed,
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每週查看量錶，我的生活因而改變了，
15:46
because I started doing experiments and seeing
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因為我開始實驗各種方式，
15:49
what made a difference, and my gas consumption
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看看會造成何種差異，我使用的天然氣
15:51
plummeted because I started tinkering
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大幅度下跌，因為我開始著手
15:52
with the thermostat and the timing on the heating system,
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修補恆溫裝置的管路，然後我留意加熱的時間，
15:55
and I knocked more than a half off my gas bills.
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而我的天然氣帳單少了不止一半。
15:57
There's a similar story for my electricity consumption,
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我的用電量也是類似的情況，
16:00
where switching off the DVD players, the stereos,
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將一直開着的DVD播放機，音響，
16:04
the computer peripherals that were on all the time,
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和電腦周邊設備的電源關掉，
16:07
and just switching them on when I needed them,
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只在需要的時候打開，
16:09
knocked another third off my electricity bills too.
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讓我的電費帳單減去三分一。
16:13
So we need a plan that adds up, and I've described for you
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所以我們需要循序漸進的計劃，我跟你們說過了
16:16
six big levers, and we need big action because we get
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六種大動作的手段，我們需要高調進行，因為我們有
16:19
90 percent of our energy from fossil fuels,
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九成能源來自化石燃料，
16:22
and so you need to push hard on most if not all of these levers.
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因此你們需要努力推行這些方法，至少要推行大部分。
16:26
And most of these levers have popularity problems,
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這些手段大部分都有公共安全的問題，
16:29
and if there is a lever you don't like the use of,
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而如果有哪個手段不合你意，
16:32
well please do bear in mind that means you need
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那麼請謹記，這表示你們需要
16:35
even stronger effort on the other levers.
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付出更多的努力來執行其他手段。
16:39
So I'm a strong advocate of having grown-up conversations
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我個人大力倡導理性對話，
16:42
that are based on numbers and facts, and I want to close
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討論要基於數據和事實，而我想要
16:45
with this map that just visualizes for you
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這地圖做總結，將土地與其他方面的需求
16:48
the requirement of land and so forth in order to get
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具像化給你們看，務求能讓每個人
16:52
just 16 light bulbs per person
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分到 16 個電燈泡，
16:54
from four of the big possible sources.
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由這四個有潛力的豐富資源提供。
16:58
So, if you wanted to get 16 light bulbs, remember,
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如果你們想分到 16 個電燈泡，請記住，
17:01
today our total energy consumption is 125 light bulbs' worth.
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現今我們的能源消耗量等同於 125 個電燈泡。
17:05
If you wanted 16 from wind, this map visualizes a solution
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如果你們想讓風力提供16個燈泡，這幅地圖把英國的
17:09
for the U.K. It's got 160 wind farms,
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解決方案具象化了。160 座風力發電廠，
17:12
each 100 square kilometers in size,
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每座的大小是100平方公里，
17:15
and that would be a twentyfold increase
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是今天風力發電廠總面積的
17:16
over today's amount of wind.
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二十倍大。
17:19
Nuclear power, to get 16 light bulbs per person, you'd need
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核能，如果要每人分到 16 個電燈泡，你們需要
17:22
two gigawatts at each of the purple dots on the map.
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讓這張地圖上的每個紫點提供二十億瓦的能源
17:24
That's a fourfold increase
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這個升幅是現今核能發電量的
17:26
over today's levels of nuclear power.
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四倍之多。
17:29
Biomass, to get 16 light bulbs per person, you'd need
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至於生質發電，如果要每人分到 16 個電燈泡，你們需要
17:32
a land area something like three and a half Wales' worth,
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的土地面積大約是三個半的威爾斯公國，
17:36
either in our country, or in someone else's country,
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不是蓋在我們國家，就是蓋在別的國家，
17:40
possibly Ireland, possibly somewhere else. (Laughter)
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可能是愛爾蘭，可能是其他地方。(眾笑)
17:43
And a fourth supply side option, concentrating solar power
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而第四個替代供應方案，把別人的沙漠
17:46
in other people's deserts,
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的太陽能集中運用，
17:48
if you wanted to get 16 light bulbs' worth,
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如果你們想分到 16 個電燈泡的電力，
17:50
then we're talking about these eight hexagons
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那我們就要說到右下方
17:53
down at the bottom right.
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這八個六角形。
17:54
The total area of those hexagons
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這些六角形的總面積
17:57
is two Greater London's worth of someone else's Sahara,
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是別人的撒哈拉沙漠，佔地是大倫敦地區的兩倍，
18:01
and you'll need power lines all the way across Spain
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你們需要架設輸電纜，橫越西班牙和法國，
18:03
and France to bring the power from the Sahara to Surrey.
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才能將電力由薩哈拉沙漠牽到 (英國南方的) 薩里郡。
18:08
We need a plan that adds up.
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我們需要循序漸進的方案。
18:12
We need to stop shouting and start talking,
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我們要停止吵鬧，開始討論，
18:16
and if we can have a grown-up conversation,
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如果我們的對話夠理性，
18:19
make a plan that adds up and get building,
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設定一個循序漸進的計劃，開始建設，
18:22
maybe this low-carbon revolution
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或許這場低碳革命
18:24
will actually be fun. Thank you very much for listening.
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到頭來會相當有趣。非常感謝大家的聆聽。
18:26
(Applause)
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(掌聲)
ABOUT THE SPEAKER
David MacKay - ProfessorAs an information theorist and computer scientist, David MacKay uses hard math to assess our renewable energy options.
Why you should listen
David MacKay is a professor of Natural Philosophy in the Physics department at the University of Cambridge and chief scientific adviser to the UK Department of Energy and Climate Change. He received a degree in Experimental and Theoretical Physics from Trinity College and a PhD. in Computation and Neural Systems as a Fulbright Scholar at Caltech. In 1992, MacKay was made the Royal Society Smithson Research Fellow at Darwin College at University of Cambridge and was elected a Fellow of the Royal Society in May 2009. He has also taught at the African Institute for Mathematical Sciences in Cape Town. In 2003, his book Information Theory, Inference, and Learning Algorithms was published and, in 2008, he self-published Sustainable Energy — Without the Hot Air. Both books are fully available for free online.
David MacKay | Speaker | TED.com