1. Shale gas and climate change: worse than coal?
Kees van der Leun
11 April 2011

2. EU long-term goal for GHG emissions
European Council: -80 … -95% by 2050, compared to 1990
Consequence: zero-emission energy supply by 2050
The Energy Report (WWF/Ecofys 2010) shows how this can be done on a global scale

3. Fossils are phased out over time as renewables take up the challenge
The Energy Report - Transition to a fully sustainable global energy system by 2050
Fossils are phased out over time as renewables take up the challenge
Explain axes:
Horizontal: time
Vertical: final energy (Final energy means energy as purchased by end user; as opposed to ‘primary energy’, i.e. the (higher) quantity needed before conversion (e.g. in power plants).
In the baseline, energy demand would almost double by 2050, much of this increase having to be met by non-renewable energy sources.
In contrast, the main assumptions in the TER approach are (in order of priority!):
Reduce energy demand through ambitious energy efficiency and shift demand to the power sector through electrification without a reduction in energy services
Supply this reduced energy demand from renewable sources in this priority order:
Non-bio RES (mostly for power)
Bio RES (mostly for fuel and heat)
Fossil & Nuclear (when RES not sufficient)
Use currently available technology only
Source: Ecofys

4. 95% renewable energy worldwide by 2050 is possible
The Energy Report - Transition to a fully sustainable global energy system by 2050
95% renewable energy worldwide by 2050 is possible
Source: Ecofys
… but needs strong commitments from both: governments and companies.
Ambitious policy instruments in place by 2010 – 2012 leading to:
Peak in worldwide energy demand by 2020
Total final consumption of ~260 EJ/a in 2050
95% of supply from renewable sources by 2050
Groups are :
Bio (mainly for heat and fuel): shades of green
Other renewables (mainly for electricity, some heat): the rainbow below that
Grey: Remaining fossil (5%) is for processes for which at present no renewable energy alternative is available
Bio priority:
First use all other renewables, then Bio.
In Bio: First take residues, then crops.
From 2030, algae come into the equation (too expensive before that)
Overall Bio % in final energy in 2050: 40% (~100EJ)
Wind/Solar: ~45%
Other RES: ~10%

5. Natural gas as transition fuel
Lower GHG emissions than coal
Clean-burning
Allows for flexible power plants, necessary in a system with varying supply (wind, solar) and demand (air conditioning)

6. Emissions from ‘conventional’ natural gas
Direct emissions
56 kg/GJ i.e. 40% less than bituminous coal
Indirect emissions from fossil fuel use in extraction and transport
4 kg/GJ
Indirect emissions from fugitive methane
Strongly dependent on leaking fraction (%) and time horizon
Leaking fraction: 1.7 – 6.0%

7. Methane emissions
Methane is more powerful greenhouse gas than CO2: a molecule leaking has much larger effect than a molecule being burned
Global Warming Potential (GWP) is effect of 1 kg CH4 relative to 1 kg CO2

8. Methane concentration rising again

9. Fugitive methane emissions (Howarth e.a.)