Net Zero The UK’s contribution to stopping global

warming

Committee on Climate Change

3 June 2019

1) Science and international context

Climate science and international circumstances

The world is warming due to human influence and has already reach 1°C above preindustrial levels

Source: HadCRUT4, NOAA, NASA and Cowtan & Way datasets; IPCC (2018) Chapter 1 - Framing and Context 6

Observed and human-induced warming

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1850

1860

1870

1880

1890

1900

1910

1920

1930

1940

1950

1960

1970

1980

1990

2000

2010

Warm

ing

(°

C -

rela

tive t

o 1

850

-19

00

)

Observations

Human-inducedwarming

The Paris Agreement refers to a range of temperature outcomes. It needs to be interpreted for

setting national long-term targets

7

Paris Agreement long-term temperature goal:

… holding the increase in the global average temperature to well below 2°C above

pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C

above pre-industrial levels, recognizing that this would significantly reduce the risks

and impacts of climate change.

Source: HadCRUT4, NOAA, NASA and Cowtan & Way datasets; IPCC (2018) Chapter 1 - Framing and Context 8

Observed and human-induced warming

0

0.5

1

1.5

2

2.5

3

2010

2015

2020

2025

2030

2035

2040

2045

2050

2055

2060

2065

2070

2075

2080

2085

2090

2095

2100

Wa

rmin

g (°C

-re

lati

ve

to

18

50

-1900)

Indicative >50% 1.5°Cpathway

Indicative >66% 2°Cpathway

The Paris Agreement refers to a range of temperature outcomes. It needs to be interpreted for

setting national long-term targets

-20

-10

0

10

20

30

40

50

60

1990

2000

2010

2020

2030

2040

2050

2060

2070

2080

2090

2100CO

2 e

mis

sio

ns

(GtC

O2

/yr)

Global emissions pathways consistent with Paris show declining CO2 emissions rapidly to net-zero

9

Global emissions pathways consistent with ParisCO2 (left) Aggregated GHGs (right)

-20

-10

0

10

20

30

40

50

60

1990

2000

2010

2020

2030

2040

2050

2060

2070

2080

2090

2100

Gre

en

ho

use

gas

em

issi

on

s (G

tCO

2e/y

r)

>66% 2°C -

Range

>50% 1.5°C -

Range

>50% 1.5°C -

Median

>66% 2°C -

Median

Historical

Source: Huppmann, D. et al. (2018) A new scenario resource for

integrated 1.5°C research.

-20

-10

0

10

20

30

40

50

60

1990

2000

2010

2020

2030

2040

2050

2060

2070

2080

2090

2100CO

2 e

mis

sio

ns

(GtC

O2

/yr)

Global emissions pathways consistent with ParisCO2 (left) Aggregated GHGs (right)

-20

-10

0

10

20

30

40

50

60

1990

2000

2010

2020

2030

2040

2050

2060

2070

2080

2090

2100

Gre

en

ho

use

gas

em

issi

on

s (G

tCO

2e/y

r)

>66% 2°C -

Range

>50% 1.5°C -

Range

>50% 1.5°C -

Median

>66% 2°C -

Median

Historical

Source: Huppmann, D. et al. (2018) A new scenario resource for

integrated 1.5°C research.

13

Global emissions pathways consistent with Paris show declining CO2 emissions rapidly to net-zero

Source: Huppmann, D. et al. (2018) A new scenario

resource for integrated 1.5°C research.

13

Timing of peak warming is much more closely connected to the timing of net-zero CO2 than for all GHGs

2030

2040

2050

2060

2070

2080

2090

2100

2110

2030

2040

2050

2060

2070

2080

2090

2100

2110

Date

of

peak w

arm

ing

Date of net-zero emissions

GHG

CO₂

1:1 line

Reaching net-zero GHG will end the UK’s impact on global warming

12

UK impact on global temperature under hypothetical future emissions pathways

Source: CCC Analysis

0.000

0.001

0.002

0.003

0.004

0.005

0.006

2020

2025

2030

2035

2040

2045

2050

2055

2060

2065

2070

UK

co

ntr

ibu

tio

n t

o w

arm

ing

(°

C -

rela

tive t

o 2

020)

Net-zero 2045

Net-zero 2050

Net-zero 2060 (90%reduction in 2050)

Net-zero 2070 (80%reduction in 2050)

80% reduction in 2050(maintained)

1) Science and international context

An appropriate UK contribution to the global effort

A revised UK long-term emissions target should reflect the structure of the Paris Agreement

14

Key features of the Paris Agreement:

• Largely ‘bottom-up’ structure. Emissions allowances are not and will not be

allocated centrally to countries

• Reductions to be set according to ‘highest possible ambition’

• Equity and fairness remain core principles, developed countries are expected to

take the lead.

Historical rates of per person emissions reduction in the UK have been similar to what is required from world as a whole

Source: Huppmann, D. et al. (2018) A new scenario resource for integrated 1.5°C research 16

Evolution of global per capita emissions over time

-5

-3

-1

1

3

5

7

9

11

13

15

1990

2000

2010

2020

2030

2040

2050

2060

2070

2080

2090

2100G

HG

em

issi

on

s p

er

cap

ita

(tC

O2e/p

ers

on

/yr)

>66% 2°C - Range

>50 %1.5°C - Range

>50% 1.5°C - Median

>66% 2°C - Median

Historical - World

Source: Huppmann, D. et al. (2018) A new scenario resource for integrated 1.5°C research 17

Evolution of global per capita emissions over time

-5

-3

-1

1

3

5

7

9

11

13

15

1990

2000

2010

2020

2030

2040

2050

2060

2070

2080

2090

2100G

HG

em

issi

on

s p

er

cap

ita

(tC

O2

e/p

ers

on

/yr)

>66% 2°C - Range

>50 %1.5°C - Range

>50% 1.5°C - Median

>66% 2°C - Median

Historical - World

Historical - UK

Historical rates of per person emissions reduction in the UK have been similar to what is required from world as a whole

1) Science and international context

Supporting increased global ambition

A UK net-zero target would support raising international ambition ahead of the UN climate summit in September

22

2019: conclude Article 6 market

mechanisms negotiations

By 2020: updated NDCs by all parties;

submit low-emissions

development pathways

2021

2022

2023: 1st stocktake on mitigation,

adaptation, finance & technology

transfer

2024

By 2025: next-round

NDCs submission

by all parties

Near-term diplomatic timetable

June 2019:

indication of COP26

hosting (Bonn); G20

(Japan)

Sep 2019: NDC’s 1st

possible uplift (UN

S.G. Summit, NY)

Dec 2019: COP26

hosting decision

(COP25, Chile)

Early 2020: EU

updated long-

term target

submission

Nov 2020:

COP26 (in

UK?)

2) Reaching net-zero emissions in the UK

UK scenarios

Reaching net-zero emissions in the UKBuilding UK net-zero scenarios

There is a range of technologies and behaviour changes that can help reduce emissions.

We split these into ‘Core’, ‘Further Ambition’ and ‘Speculative’ options:

• Core options are low-cost, low-regret options that make sense under most strategies to meet the current 80% 2050 target

• Further Ambition options are more challenging and generally more expensive than the Core options

• Speculative options currently have very low levels of technology readiness, very high costs, or significant barriers to public acceptability

24

Reaching net-zero emissions in the UKHow UK net-zero scenarios can be delivered

25

H2 H2H2H2 H2H2

Energy supply Energy use Land

CO2 storage

H2H2H2 H2H2

Reaching net-zero emissions in the UKHow UK net-zero scenarios can be delivered

26

H2 H2H2H2 H2H2

Energy supply Energy use Land

CO2 storage

H2H2H2 H2H2

Reaching net-zero emissions in the UKRemaining emissions in the Further Ambition scenario

27

Remaining emissions by sector (left) and type of gas (right)

-80

-60

-40

-20

0

20

40

60

80

100

2050 2050

MtC

O2

e

F-gases

Nitrous oxide

Methane

Carbon dioxide

Shipping

F-gases

Surface transport

Power

Hydrogen production

Buildings

Waste

Industry

Agriculture

Aviation

Engineered removals

LULUCF

Source: CCC analysis

Reaching net-zero emissions in the UKA mix of Speculative options is likely to be needed

28

Source: CCC analysis

0 10 20 30 40 50 60

Carbon-neutral

synthetic fuels

Engineered removals

Deeper roll-out of

Further Ambition

options

MtCO2e

Diet change

Afforestation

Aviation demand

Higher CCS capture rate

Peatland restoration

Bioenergy crops

Hydrogen in buildings

Hydrogen in industry

Hydrogen trains

AR5 GWPs

BECCS DACCS

In aviation, industry & buildings

Range for

net-zero

Additional abatement potential from Speculative options in 2050

Reaching net-zero emissions in the UKPeople need to be engaged

29

Role of societal and behavioural changes

38%

53%

9%

Low-carbon technologies or fuels not

societal / behavioural changes

Measures with a combination of low-

carbon technologies and societal /

behavioural changes

Largely societal or behavioural changes

Source: CCC analysis

2) Reaching net-zero emissions in the UK

Costs and benefits

Reaching net-zero emissions in the UKCosts are far lower than we imagined

31

The importance of innovationCosts of example low-carbon technologies compared to past projections

Offshore wind (left) Battery packs for electric vehicles (right)

0

50

100

150

200

250

2016

2020

2025

2030

Leveli

sed

cost

of

ele

ctri

city

-£

/MW

h

(£2

01

8)

DECCestimate(2012)

Contractssigned in2013

Contractssigned in2015

Contractssigned in2017

0

200

400

600

800

1000

1200

2010

2015

2020

2025

2030

Batt

ery

pack

co

st -

$/K

Wh

(£

20

18

)

CCCcentralestimate(2011)

Actualaveragecost

Source: Offshore wind costs, CCC analysis based on DECC (2012) Electricity generation costs and LCCC (2019) CfD register. Battery forecasts,

CCC (2015) Sectoral scenarios for the 5th Carbon Budget, outturn costs from BNEF (2018) Electric cars to reach price parity by 2022

Reaching net-zero emissions in the UKThe sooner we switch to electric vehicles the better

32

A 2030 switchover to electric vehicles would save more money than a 2040 switchover

-12

-10

-8

-6

-4

-2

0

2

2020

2022

2024

2026

2028

2030

2032

2034

2036

2038

2040

2042

2044

2046

2048

2050

Net co

st o

f sw

itch

ing t

o e

lect

ric

cars

and

vans

(£b

n/y

ear) 2040 phase-out

2030 phase-out

Source: CCC analysis

Reaching net-zero emissions in the UKNo extra cost than already expected

33

2050 target (v 1990) Estimated cost

2003: -60% CO2 0.5-2.0% of GDP

2008: -80% GHG 1-2% of GDP

Now: -100% GHG 1-2% of GDP

Co-benefits Clean Growth

More effort

Same cost

3) Recommendations