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When the Industrial Revolution started,

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the amount of carbon sitting
underneath Britain in the form of coal

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was as big as the amount of carbon
sitting under Saudi Arabia

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in the form of oil.

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This carbon powered
the Industrial Revolution,

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it put the "Great" in Great Britain,

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and led to Britain's temporary
world domination.

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And then, in 1918,
coal production in Britain peaked,

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and has declined ever since.

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In due course, Britain started using
oil and gas from the North Sea,

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and in the year 2000,

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oil and gas production
from the North Sea also peaked,

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and they're now on the decline.

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These observations about the finiteness

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of easily accessible, local,
secure fossil fuels,

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is a motivation for saying,
"Well, what's next?

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What is life after fossil fuels
going to be like?

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Shouldn't we be thinking hard
about how to get off fossil fuels?"

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Another motivation,
of course, is climate change.

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And when people talk
about life after fossil fuels

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and climate change action,

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I think there's a lot of fluff,

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a lot of greenwash,
a lot of misleading advertising,

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and I feel a duty as a physicist to try
to guide people around the claptrap

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and help people understand the actions
that really make a difference,

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and to focus on ideas that do add up.

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Let me illustrate this

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with what physicists call
a back-of-envelope calculation.

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We love back-of-envelope calculations.

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You ask a question,
write down some numbers,

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and get an answer.

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It may not be very accurate,
but it may make you say, "Hmm."

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So here's a question:

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Imagine if we said, "Oh yes,
we can get off fossil fuels.

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We'll use biofuels. Problem solved.

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Transport ... We don't need oil anymore."

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Well, what if we grew
the biofuels for a road

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on the grass verge
at the edge of the road?

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How wide would the verge
have to be for that to work out?

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OK, so let's put in some numbers.

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Let's have our cars go
at 60 miles per hour.

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Let's say they do 30 miles per gallon.

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That's the European average for new cars.

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Let's say the productivity
of biofuel plantations

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is 1,200 liters of biofuel
per hectare per year.

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That's true of European biofuels.

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And let's imagine the cars are spaced
80 meters apart from each other,

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and they're perpetually
going along this road.

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The length of the road doesn't matter,

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because the longer the road,
the more biofuel plantation.

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What do we do with these numbers?

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Take the first number, divide by the other
three, and get eight kilometers.

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And that's the answer.

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That's how wide the plantation
would have to be,

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given these assumptions.

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And maybe that makes you say, "Hmm.

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Maybe this isn't going
to be quite so easy."

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And it might make you think,

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perhaps there's an issue to do with areas.

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And in this talk, I'd like to talk
about land areas, and ask:

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Is there an issue about areas?

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The answer is going to be yes,
but it depends which country you are in.

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So let's start in the United Kingdom,

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since that's where we are today.

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The energy consumption
of the United Kingdom,

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the total energy consumption --
not just transport, but everything --

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I like to quantify it in lightbulbs.

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It's as if we've all got
125 lightbulbs on all the time,

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125 kilowatt-hours per day per person

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is the energy consumption of the UK.

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So there's 40 lightbulbs'
worth for transport,

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40 lightbulbs' worth for heating,

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and 40 lightbulbs' worth
for making electricity,

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and other things are relatively small,

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compared to those three big fish.

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It's actually a bigger footprint
if we take into account

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the embodied energy in the stuff
we import into our country as well.

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And 90 percent of this energy, today,
still comes from fossil fuels,

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and 10 percent, only, from other,
greener -- possibly greener -- sources,

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like nuclear power and renewables.

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So.

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That's the UK.

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The population density of the UK
is 250 people per square kilometer.

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I'm now going to show you other countries
by these same two measures.

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On the vertical axis, I'm going
to show you how many lightbulbs --

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what our energy consumption per person is.

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We're at 125 lightbulbs per person,

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and that little blue dot there
is showing you the land area

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of the United Kingdom.

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The population density
is on the horizontal axis,

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and we're 250 people per square kilometer.

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Let's add European countries in blue,

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and you can see there's quite a variety.

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I should emphasize,
both of these axes are logarithmic;

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as you go from one gray bar
to the next gray bar,

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you're going up a factor of 10.

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Next, let's add Asia in red,

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the Middle East and North Africa in green,

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sub-Saharan Africa in blue,

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black is South America,

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purple is Central America,

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and then in pukey-yellow,
we have North America,

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Australia and New Zealand.

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You can see the great diversity
of population densities

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00:05:03,374 --> 00:05:05,961
and of per capita consumptions.

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Countries are different from each other.

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Top left, we have Canada and Australia,
with enormous land areas,

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very high per capita consumption --
200 or 300 lightbulbs per person --

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and very low population densities.

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Top right: Bahrain has
the same energy consumption

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per person, roughly, as Canada --

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over 300 lightbulbs per person,

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but their population density
is a factor of 300 times greater,

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1,000 people per square kilometer.

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Bottom right: Bangladesh has
the same population density as Bahrain,

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but consumes 100 times less per person.

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Bottom left: well, there's no one.

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But there used to be
a whole load of people.

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Here's another message from this diagram.

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I've added on little blue tails
behind Sudan, Libya,

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China, India, Bangladesh.

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That's 15 years of progress.

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Where were they 15 years ago,
and where are they now?

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And the message is,

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most countries are going to the right,
and they're going up.

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Up and to the right:
bigger population density

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and higher per capita consumption.

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00:06:05,626 --> 00:06:09,581
So, we may be off in the top
right-hand corner, slightly unusual,

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the United Kingdom accompanied by Germany,

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Japan, South Korea, the Netherlands,

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and a bunch of other
slightly odd countries,

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but many other countries are coming
up and to the right to join us.

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So we're a picture, if you like,

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of what the future energy consumption

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might be looking
like in other countries, too.

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I've also added in this diagram
now some pink lines

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that go down and to the right.

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Those are lines of equal
power consumption per unit area,

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which I measure in watts per square meter.

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So, for example, the middle line there,
0.1 watts per square meter,

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is the energy consumption
per unit area of Saudi Arabia,

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Norway, Mexico in purple,
and Bangladesh 15 years ago.

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Half of the world's population
lives in countries

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that are already above that line.

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The United Kingdom is consuming
1.25 watts per square meter.

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So is Germany, and Japan
is consuming a bit more.

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So, let's now say why this is relevant.

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Why is it relevant?

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Well, we can measure
renewables in the same units

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and other forms of power
production in the same units.

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Renewables is one of the leading ideas

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for how we could get off
our 90 percent fossil-fuel habit.

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So here come some renewables.

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Energy crops deliver
half a watt per square meter

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in European climates.

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What does that mean?

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You might have anticipated that result,

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given what I told you about the biofuel
plantation a moment ago.

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Well, we consume 1.25 watts
per square meter.

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What this means is,

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even if you covered the whole
of the United Kingdom with energy crops,

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you couldn't match
today's energy consumption.

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Wind power produces a bit more --
2.5 watts per square meter.

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But that's only twice as big
as 1.25 watts per square meter.

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So that means if you wanted, literally,
to produce total energy consumption

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in all forms, on average, from wind farms,

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you need wind farms
half the area of the UK.

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I've got data to back up
all these assertions, by the way.

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Next, let's look at solar power.

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Solar panels, when you put them on a roof,

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deliver about 20 watts
per square meter in England.

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If you really want to get
a lot from solar panels,

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you need to adopt the traditional
Bavarian farming method,

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where you leap off the roof,

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and coat the countryside
with solar panels, too.

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Solar parks, because of the gaps
between the panels, deliver less.

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They deliver about 5 watts
per square meter of land area.

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And here's a solar park
in Vermont, with real data,

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delivering 4.2 watts per square meter.

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Remember where we are,
1.25 watts per square meter,

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wind farms 2.5, solar parks about five.

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So whichever of those renewables you pick,

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the message is, whatever mix
of those renewables you're using,

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if you want to power the UK on them,

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00:09:04,129 --> 00:09:06,230
you're going to need
to cover something like

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00:09:06,254 --> 00:09:09,112
20 percent or 25 percent of the country

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00:09:09,136 --> 00:09:10,775
with those renewables.

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I'm not saying that's a bad idea;
we just need to understand the numbers.

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I'm absolutely not anti-renewables.
I love renewables.

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00:09:17,282 --> 00:09:18,918
But I'm also pro-arithmetic.

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00:09:18,942 --> 00:09:20,647
(Laughter)

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00:09:20,671 --> 00:09:24,803
Concentrating solar power in deserts
delivers larger powers per unit area,

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00:09:24,827 --> 00:09:27,178
because you don't have
the problem of clouds.

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So, this facility delivers
14 watts per square meter;

195
00:09:30,430 --> 00:09:32,141
this one 10 watts per square meter;

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00:09:32,165 --> 00:09:34,921
and this one in Spain,
5 watts per square meter.

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00:09:34,945 --> 00:09:37,119
Being generous
to concentrating solar power,

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00:09:37,143 --> 00:09:40,807
I think it's perfectly credible it could
deliver 20 watts per square meter.

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00:09:40,831 --> 00:09:41,997
So that's nice.

200
00:09:42,021 --> 00:09:44,573
Of course, Britain
doesn't have any deserts.

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00:09:44,955 --> 00:09:46,111
Yet.

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00:09:46,135 --> 00:09:47,820
(Laughter)

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00:09:47,844 --> 00:09:50,209
So here's a summary so far:

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00:09:51,035 --> 00:09:53,659
All renewables, much
as I love them, are diffuse.

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00:09:53,683 --> 00:09:55,722
They all have a small power per unit area,

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00:09:55,746 --> 00:09:57,541
and we have to live with that fact.

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00:09:58,271 --> 00:10:03,563
And that means, if you do want renewables
to make a substantial difference

208
00:10:03,587 --> 00:10:05,375
for a country like the United Kingdom

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00:10:05,399 --> 00:10:07,491
on the scale of today's consumption,

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00:10:07,515 --> 00:10:11,916
you need to be imagining renewable
facilities that are country-sized.

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00:10:11,940 --> 00:10:13,253
Not the entire country,

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00:10:13,277 --> 00:10:16,644
but a fraction of the country,
a substantial fraction.

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00:10:17,684 --> 00:10:20,231
There are other options
for generating power as well,

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00:10:20,255 --> 00:10:21,939
which don't involve fossil fuels.

215
00:10:21,963 --> 00:10:25,118
So there's nuclear power,
and on this ordinance survey map,

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00:10:25,142 --> 00:10:28,881
you can see there's a Sizewell B
inside a blue square kilometer.

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00:10:28,905 --> 00:10:30,908
That's one gigawatt in a square kilometer,

218
00:10:30,932 --> 00:10:33,357
which works out to 1,000 watts
per square meter.

219
00:10:33,381 --> 00:10:35,517
So by this particular metric,

220
00:10:35,541 --> 00:10:40,736
nuclear power isn't
as intrusive as renewables.

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00:10:41,322 --> 00:10:43,317
Of course, other metrics matter, too,

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00:10:43,341 --> 00:10:46,051
and nuclear power has
all sorts of popularity problems.

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00:10:46,964 --> 00:10:49,001
But the same goes for renewables as well.

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00:10:49,025 --> 00:10:51,853
Here's a photograph of a consultation
exercise in full swing

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00:10:51,877 --> 00:10:54,565
in the little town of Penicuik
just outside Edinburgh,

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00:10:54,589 --> 00:10:57,083
and you can see the children
of Penicuik celebrating

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00:10:57,107 --> 00:10:59,477
the burning of the effigy of the windmill.

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00:10:59,501 --> 00:11:00,660
So --

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00:11:00,684 --> 00:11:01,734
(Laughter)

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00:11:01,758 --> 00:11:03,087
People are anti-everything,

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00:11:03,111 --> 00:11:05,769
and we've got to keep
all the options on the table.

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00:11:06,328 --> 00:11:09,967
What can a country like the UK
do on the supply side?

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00:11:09,991 --> 00:11:12,910
Well, the options are,
I'd say, these three:

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00:11:12,934 --> 00:11:14,112
power renewables,

235
00:11:14,136 --> 00:11:17,847
and recognizing that they need
to be close to country-sized;

236
00:11:17,871 --> 00:11:19,117
other people's renewables,

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00:11:19,141 --> 00:11:21,268
so we could go back and talk very politely

238
00:11:21,292 --> 00:11:24,329
to the people in the top left-hand side
of the diagram and say,

239
00:11:24,353 --> 00:11:26,604
"Uh, we don't want
renewables in our backyard,

240
00:11:26,628 --> 00:11:29,222
but, um, please could we put
them in yours instead?"

241
00:11:29,246 --> 00:11:31,211
And that's a serious option.

242
00:11:31,235 --> 00:11:34,819
It's a way for the world
to handle this issue.

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00:11:34,843 --> 00:11:38,975
So countries like Australia,
Russia, Libya, Kazakhstan,

244
00:11:38,999 --> 00:11:41,999
could be our best friends
for renewable production.

245
00:11:43,356 --> 00:11:45,392
And a third option is nuclear power.

246
00:11:45,416 --> 00:11:47,632
So that's some supply-side options.

247
00:11:47,656 --> 00:11:50,948
In addition to the supply levers
that we can push --

248
00:11:50,972 --> 00:11:53,007
and remember, we need large amounts,

249
00:11:53,031 --> 00:11:56,558
because at the moment, we get 90 percent
of our energy from fossil fuels --

250
00:11:56,582 --> 00:11:57,942
in addition to those levers,

251
00:11:57,966 --> 00:12:01,017
we could talk about other ways
of solving this issue.

252
00:12:01,041 --> 00:12:04,437
Namely, we could reduce demand,
and that means reducing population --

253
00:12:04,461 --> 00:12:06,276
I'm not sure how to do that --

254
00:12:06,300 --> 00:12:09,112
or reducing per capita consumption.

255
00:12:09,136 --> 00:12:11,599
So let's talk about three more big levers

256
00:12:11,623 --> 00:12:13,949
that could really help
on the consumption side.

257
00:12:13,973 --> 00:12:15,127
First, transport.

258
00:12:15,151 --> 00:12:16,694
Here are the physics principles

259
00:12:16,718 --> 00:12:19,768
that tell you how to reduce
the energy consumption of transport.

260
00:12:19,792 --> 00:12:22,238
People often say,
"Technology can answer everything.

261
00:12:22,262 --> 00:12:25,038
We can make vehicles
that are 100 times more efficient."

262
00:12:25,062 --> 00:12:27,042
And that's almost true. Let me show you.

263
00:12:27,066 --> 00:12:29,534
The energy consumption
of this typical tank here

264
00:12:29,558 --> 00:12:32,982
is 80 kilowatt hours
per hundred person kilometers.

265
00:12:33,006 --> 00:12:36,801
That's the average European car.

266
00:12:37,347 --> 00:12:38,498
Eighty kilowatt hours.

267
00:12:38,522 --> 00:12:40,610
Can we make something 100 times better

268
00:12:40,634 --> 00:12:42,947
by applying the physics
principles I just listed?

269
00:12:42,971 --> 00:12:44,614
Yes. Here it is. It's the bicycle.

270
00:12:44,638 --> 00:12:47,284
It's 80 times better
in energy consumption,

271
00:12:47,308 --> 00:12:49,532
and it's powered by biofuel, by Weetabix.

272
00:12:49,556 --> 00:12:51,694
(Laughter)

273
00:12:51,718 --> 00:12:53,585
And there are other options in between,

274
00:12:53,609 --> 00:12:55,736
because maybe the lady
in the tank would say,

275
00:12:55,760 --> 00:12:58,916
"No, that's a lifestyle change.
Don't change my lifestyle, please."

276
00:12:58,940 --> 00:13:02,587
We could persuade her to take a train,
still a lot more efficient than a car,

277
00:13:02,611 --> 00:13:04,386
but that might be a lifestyle change.

278
00:13:04,410 --> 00:13:05,994
Or there's the EcoCAR, top-left.

279
00:13:06,018 --> 00:13:09,753
It comfortably accommodates one teenager
and it's shorter than a traffic cone,

280
00:13:09,777 --> 00:13:11,813
and it's almost as efficient as a bicycle,

281
00:13:11,837 --> 00:13:14,877
as long as you drive it
at 15 miles per hour.

282
00:13:15,299 --> 00:13:17,526
In between, perhaps
some more realistic options

283
00:13:17,550 --> 00:13:20,515
on the transport lever
are electric vehicles,

284
00:13:20,539 --> 00:13:22,918
so electric bikes
and electric cars in the middle,

285
00:13:22,942 --> 00:13:27,968
perhaps four times as energy efficient
as the standard petrol-powered tank.

286
00:13:28,778 --> 00:13:30,676
Next, there's the heating lever.

287
00:13:30,700 --> 00:13:34,191
Heating is a third of our energy
consumption in Britain,

288
00:13:34,215 --> 00:13:36,288
and quite a lot of that
is going into homes

289
00:13:36,312 --> 00:13:37,695
and other buildings,

290
00:13:37,719 --> 00:13:39,696
doing space heating and water heating.

291
00:13:39,720 --> 00:13:42,004
So here's a typical crappy British house.

292
00:13:42,028 --> 00:13:44,747
It's my house, with a Ferrari out front.

293
00:13:44,771 --> 00:13:45,836
(Laughter)

294
00:13:45,860 --> 00:13:47,013
What can we do to it?

295
00:13:47,037 --> 00:13:50,698
Well, the laws of physics
are written up there,

296
00:13:50,722 --> 00:13:55,970
which describe how the power
consumption for heating

297
00:13:55,994 --> 00:13:57,902
is driven by the things you can control.

298
00:13:57,926 --> 00:14:00,820
The things you can control
are the temperature difference

299
00:14:00,844 --> 00:14:02,527
between the inside and the outside.

300
00:14:02,551 --> 00:14:05,165
There's this remarkable technology
called a thermostat:

301
00:14:05,189 --> 00:14:06,925
you grasp it, rotate it to the left,

302
00:14:06,949 --> 00:14:09,478
and your energy consumption
in the home will decrease.

303
00:14:09,502 --> 00:14:12,605
I've tried it. It works.
Some people call it a lifestyle change.

304
00:14:12,629 --> 00:14:13,713
(Laughter)

305
00:14:13,737 --> 00:14:17,217
You can also get the fluff men
in to reduce the leakiness

306
00:14:17,241 --> 00:14:20,210
of your building -- put fluff
in the walls, fluff in the roof,

307
00:14:20,234 --> 00:14:22,028
a new front door, and so forth.

308
00:14:23,452 --> 00:14:26,037
The sad truth is,
this will save you money.

309
00:14:26,061 --> 00:14:27,401
That's not sad, that's good.

310
00:14:27,425 --> 00:14:28,603
But the sad truth is,

311
00:14:28,627 --> 00:14:31,826
it'll only get about 25 percent
of the leakiness of your building

312
00:14:31,850 --> 00:14:34,545
if you do these things,
which are good ideas.

313
00:14:34,569 --> 00:14:37,828
If you really want to get a bit closer
to Swedish building standards

314
00:14:37,852 --> 00:14:39,502
with a crappy house like this,

315
00:14:39,526 --> 00:14:42,972
you need to be putting
external insulation on the building,

316
00:14:42,996 --> 00:14:45,268
as shown by this block of flats in London.

317
00:14:46,652 --> 00:14:49,657
You can also deliver heat
more efficiently using heat pumps,

318
00:14:49,681 --> 00:14:53,151
which use a smaller bit
of high-grade energy like electricity

319
00:14:53,175 --> 00:14:55,740
to move heat from your garden
into your house.

320
00:14:56,676 --> 00:14:59,046
The third demand-side option
I want to talk about,

321
00:14:59,070 --> 00:15:02,216
the third way to reduce energy
consumption is: read your meters.

322
00:15:02,240 --> 00:15:04,069
People talk a lot about smart meters,

323
00:15:04,093 --> 00:15:05,440
but you can do it yourself.

324
00:15:05,464 --> 00:15:07,389
Use your own eyes and be smart.

325
00:15:07,413 --> 00:15:11,076
Read your meter, and if you're anything
like me, it'll change your life.

326
00:15:11,100 --> 00:15:12,532
Here's a graph I made.

327
00:15:12,556 --> 00:15:14,700
I was writing a book
about sustainable energy,

328
00:15:14,724 --> 00:15:15,878
and a friend asked me,

329
00:15:15,902 --> 00:15:17,716
"How much energy do you use at home?"

330
00:15:17,740 --> 00:15:19,760
I was embarrassed; I didn't actually know.

331
00:15:19,784 --> 00:15:21,985
And so I started reading
the meter every week.

332
00:15:22,009 --> 00:15:25,801
The old meter readings are shown
in the top half of the graph,

333
00:15:25,825 --> 00:15:28,050
and then 2007 is shown
in green at the bottom.

334
00:15:28,074 --> 00:15:30,396
That was when I was reading
the meter every week.

335
00:15:30,420 --> 00:15:31,586
And my life changed,

336
00:15:31,610 --> 00:15:34,965
because I started doing experiments
and seeing what made a difference.

337
00:15:34,989 --> 00:15:36,394
My gas consumption plummeted,

338
00:15:36,418 --> 00:15:38,637
because I started tinkering
with the thermostat

339
00:15:38,661 --> 00:15:40,460
and the timing on the heating system,

340
00:15:40,484 --> 00:15:42,697
and I knocked more than half
off my gas bills.

341
00:15:42,721 --> 00:15:45,604
There's a similar story
for my electricity consumption,

342
00:15:45,628 --> 00:15:49,190
where switching off the DVD
players, the stereos,

343
00:15:49,214 --> 00:15:52,008
the computer peripherals
that were on all the time,

344
00:15:52,032 --> 00:15:54,227
and just switching them on
when I needed them,

345
00:15:54,251 --> 00:15:56,876
knocked another third
off my electricity bills, too.

346
00:15:58,142 --> 00:15:59,908
So we need a plan that adds up.

347
00:15:59,932 --> 00:16:02,522
I've described for you six big levers.

348
00:16:02,546 --> 00:16:03,712
We need big action,

349
00:16:03,736 --> 00:16:06,498
because we get 90 percent
of our energy from fossil fuels,

350
00:16:06,522 --> 00:16:10,568
and so you need to push hard
on most, if not all, of these levers.

351
00:16:11,288 --> 00:16:13,574
Most of these levers
have popularity problems,

352
00:16:13,598 --> 00:16:17,264
and if there is a lever
you don't like the use of,

353
00:16:17,288 --> 00:16:21,105
well, please do bear in mind
that means you need even stronger effort

354
00:16:21,129 --> 00:16:23,010
on the other levers.

355
00:16:23,456 --> 00:16:26,607
So I'm a strong advocate
of having grown-up conversations

356
00:16:26,631 --> 00:16:28,892
that are based on numbers and facts.

357
00:16:28,916 --> 00:16:32,692
And I want to close with this map
that just visualizes for you

358
00:16:32,716 --> 00:16:36,253
the requirement of land and so forth

359
00:16:36,277 --> 00:16:39,341
in order to get just
16 lightbulbs per person

360
00:16:39,365 --> 00:16:42,053
from four of the big possible sources.

361
00:16:42,474 --> 00:16:45,634
So, if you wanted to get 16 lightbulbs --

362
00:16:45,658 --> 00:16:49,979
remember, today our total energy
consumption is 125 lightbulbs' worth --

363
00:16:50,003 --> 00:16:52,226
if you wanted 16 from wind,

364
00:16:52,250 --> 00:16:55,077
this map visualizes a solution for the UK.

365
00:16:55,101 --> 00:16:59,258
It's got 160 wind farms,
each 100 square kilometers in size,

366
00:16:59,282 --> 00:17:03,166
and that would be a twentyfold increase
over today's amount of wind.

367
00:17:03,190 --> 00:17:06,098
Nuclear power:
to get 16 lightbulbs per person,

368
00:17:06,122 --> 00:17:09,211
you'd need two gigawatts
at each of the purple dots on the map.

369
00:17:09,235 --> 00:17:13,418
That's a fourfold increase
over today's levels of nuclear power.

370
00:17:14,069 --> 00:17:16,767
Biomass: to get 16 lightbulbs per person,

371
00:17:16,791 --> 00:17:21,053
you'd need a land area something
like three and a half Wales' worth,

372
00:17:21,823 --> 00:17:24,405
either in our country,
or in someone else's country,

373
00:17:24,429 --> 00:17:26,472
possibly Ireland, possibly somewhere else.

374
00:17:26,496 --> 00:17:27,575
(Laughter)

375
00:17:27,599 --> 00:17:29,390
And a fourth supply-side option:

376
00:17:29,414 --> 00:17:32,131
concentrating solar power
in other people's deserts.

377
00:17:32,554 --> 00:17:34,993
If you wanted to get 16 lightbulbs' worth,

378
00:17:35,017 --> 00:17:38,032
then we're talking
about these eight hexagons

379
00:17:38,056 --> 00:17:39,367
down at the bottom right.

380
00:17:39,391 --> 00:17:43,616
The total area of those hexagons
is two Greater London's worth

381
00:17:43,640 --> 00:17:45,729
of someone else's Sahara,

382
00:17:45,753 --> 00:17:48,760
and you'll need power lines
all the way across Spain and France

383
00:17:48,784 --> 00:17:52,154
to bring the power
from the Sahara to Surrey.

384
00:17:52,595 --> 00:17:53,745
(Laughter)

385
00:17:53,769 --> 00:17:55,363
We need a plan that adds up.

386
00:17:56,295 --> 00:17:58,797
We need to stop shouting
and start talking.

387
00:18:00,209 --> 00:18:04,432
And if we can have
a grown-up conversation,

388
00:18:04,456 --> 00:18:06,917
make a plan that adds up and get building,

389
00:18:06,941 --> 00:18:09,945
maybe this low-carbon revolution
will actually be fun.

390
00:18:09,969 --> 00:18:11,707
Thank you very much for listening.

391
00:18:11,731 --> 00:18:14,237
(Applause)