What would the world’s energy system need to look like
in 2040 in order to limit climate change to two degrees? What would
it take to get there?

One possible set of answers to those questions has
been provided by the International Energy Agency, which
published its latest World
Energy Outlook
(WEO) earlier this month.

The WEO is a set of projections looking at the future
of the world’s energy system out to 2040. It explores three
different ways today’s energy system might evolve, depending on the
policy choices we make now.

It looks at a world where no new policies are enacted,
leaving us on a path towards nearly six degrees of warming. It
considers a world where we stick to climate pledges made by
governments but not yet fulfilled. These would reduce warming below
four degrees.

Finally it considers the policy and energy system
changes that would be needed to limit climate change this century
to two degrees of warming above pre-industrial levels.

We’ve used the WEO’s findings to produce a series of
maps and charts illustrating the energy system we would need in
2040 to meet this goal. It’s going to take some big changes, but it
boils down to five massively ambitious steps.

Use energy more productively

The WEO is expecting the world’s population to
reach 9 billion in 2040, a 29 per cent increase on 2012 levels.
Global wealth is expected to more than double over the same period,
growing at 3.4 per cent per year.

Without new policies those changes would
drive a 50 per cent increase in energy use, the WEO says. But in a
two degrees world it sees the increase in energy demand being held
to just 17 per cent, going from 13,361 million tonnes of oil
equivalent in 2012 to 15,629 in 2040.

Source: World
Energy Outlook 2014
, graphic by Carbon Brief

In order to limit energy use growth in this way,
the world would have to become more than twice as productive with
its energy. On average it took the equivalent of 184 tonnes of oil
to generate a million dollars of wealth in 2012. This would need to
fall to 85 tonnes, slightly better than the current energy
productivity of the UK economy.

Even with a more energy-efficient economy it
will be a challenge to meet energy demand, as we will see below.
But if energy efficiency didn’t improve, it would be much more
difficult. That’s why the
UN Environment Program
and others emphasise
importance of using energy more productively

if we are to get on to a two degrees path.

The sorts of policies needed to drive energy
efficiency include an end to fossil fuel consumption subsidies,
worth $548 billion in 2012, and the implementation of mandatory
building efficiency standards in most parts of the

Regulations requiring new buildings to produce as much
energy as they consume would need to be rolled out from as early as
next year in the EU and follow later in other regions. The whole
world would need mandatory consumer product efficiency

Global targets for energy efficiency in the steel and
cement industries and vehicle efficiency standards that would cut
fuel use in half between 2020 and 2040 would also be needed.

Stop burning so much coal and oil

The source of our energy in a two degrees world
would also need to change. Fossil fuels’ share of global energy
supplies would need to fall from 82 per cent in 2012 to 59 per cent
in 2040.

In absolute terms the amount of energy we get
from fossil fuels would also fall by 15 per cent, meaning a shift
away from burning coal and oil, as the chart below


Source: World
Energy Outlook 2014
, graphic by Carbon Brief

Falling coal and oil use would be partially balanced
by growth in the use of cleaner-burning gas, which has carbon
emissions that are roughly half those of coal per unit of energy

However, much more energy would come from
low-carbon energy sources. Energy generated by nuclear would nearly
triple. Output from hydropower and biomass would almost double. The
largest increase in energy supplies would come from non-hydro
renewables, which would increase ten-fold and on their own more
than offset the fall in coal energy output.

Aim for net zero energy emissions

These changes would have a big impact on carbon
dioxide emissions from the energy sector, which have risen almost
every year for decades. Emissions need to reach
net zero by 2070
in order to limit dangerous climate change,
according to a recent UNEP study.

Under its two degrees scenario the IEA expects
us to be well on the way towards that goal by 2040, with
energy-related emissions 39 per cent below 2012 levels.


Source: World
Energy Outlook 2014
, graphic by Carbon Brief

Gas emissions would increase slightly and claim
a much larger share of total energy-related emissions. Most of the
drop in emissions would come from using less coal, which would fall
by two-thirds between 2012 and 2040 (left hand column,


Source: World
Energy Outlook 2014
, graphic by Carbon Brief

Coal emissions would fall a lot faster than coal
use itself. That’s because the IEA’s two degrees scenario is
heavily reliant on the widespread adoption of carbon capture and
storage (CCS), allowing some coal use to continue with much reduced

global CCS industry
is in its early stages.
Without CCS the world would either need to phase out coal more
quickly or ramp up low-carbon energy sources even faster. To get an
idea of what this means, with CCS in the mix wind power output
would need to increase ten-fold to 2040 to help limit warming to
two degrees. Without CCS wind would need to increase

Switch to electric cars and biofuel

The remaining fall in emissions shown in the two
charts above would come through burning less oil. Emissions from
oil would need to fall by a third as part of climate

When it comes to reducing oil demand it is
unsurprisingly the transport sector that comes to the fore. More
than two-thirds of the 30 per cent fall in oil use by 2040 would
come from the transport sector, the WEO shows.

Achieving this reduction would not be a case of
scrapping cars and grounding planes. Instead it would require a
major shift towards more fuel-efficient vehicles, alongside a
change in the types of fuel used.

For instance there would need to be a six-fold
increase in the amount of transport energy supplied by biofuels, as
the chart below shows. The use of “other” fuels (mainly natural
gas) would also need to increase. Some vehicles already run on gas,
usually called liquified petroleum gas (LPG).


Source: World
Energy Outlook 2014
, graphic by Carbon Brief

Finally there would need to be a six-fold
increase in the use of electricity for transportation, meaning a
massive roll-out of electric vehicles.

Close coal plants and build

But electric cars only help reduce emissions if
the electricity they run on is lower-carbon than today’s average.
Power sector decarbonisation should be one of the
top priorities
in securing a two degrees
world, the IEA says.

We’ve mapped changes to the electricity
generating capacity of different parts of the world using data from
the two degrees scenario.

The are two striking features. First, 471
gigawatts of coal-fired capacity needs to close across the US,
China and EU. Second the US, China and EU would have to add 1,991
gigawatts of non-hydro renewables capacity.


Source: World
Energy Outlook 2014
, graphic by Carbon Brief

To reach that renewables target the US, EU and
China would need to collectively add the equivalent of 381,000
onshore wind turbines at a rate of 14,000 each year until 2040. And
they would need to put solar panels on the equivalent of 214
million roofs at a rate of eight million per year. For comparison
the UK currently has around 6,000 wind turbines and 600,000 solar
roofs in total.

The map also shows the need for greater capacity
from other types of low-carbon generation, such as nuclear and
hydroelectric plants. This is particularly true in rapidly growing
developing economies in Africa, China and India. Chinese and Indian
nuclear capacity would need to grow more than ten-fold, for

The map also shows how India’s plans to expand
coal-fired generation and give its poorest citizens access to
electricity may be compatible with global action on climate – up to
a point.

The two main messages remain clear, however. The
US and EU would have to close two-thirds of their coal plants.
Chinese coal capacity would have to shrink too. Many of the coal
plants that remain would need CCS.

And the world’s non-hydro renewables capacity
would need to increase nearly ten-fold from 496 gigawatts in 2012
to 4,128 gigawatts in 2040.

The WEO is just one set of scenarios showing how
the world could change its energy use in order to limit climate
change to just two degrees of warming. Other paths to that goal
might be possible, using fewer nuclear plants, greater efforts on
energy efficiency or a more rapid roll-out of electric vehicles for

But the scale of the challenge is so large
that it’s hard to comprehend. Whichever path the world takes, that
won’t change.

Via: http://www.carbonbrief.org/blog/2014/11/the-five-massive-changes-to-how-we-use-energy-that-could-limit-climate-change/