The Role and Design of
a CO2 Standard for
Dan Rutherford, Ph.D.
NGO Observer to ICAO Emissions and Technology
Environmental Working Group
14 April 2010
Overview of the climate challenge
Introduction to an aircraft CO2 standard
– Recent policy developments
– Why an aircraft standard?
– Key design criteria
What can’t a standard do?
Business As Usual: 4X CO2 by 2050
ICAO 2050 projection
Source: IPCC Working Group III 4th Assessment Report, 2007.
In total, 3.5~5.0% of global RF in 2005, counting NOx
and cirrus impacts (Lee 2009)
Aviation CO2 missing from international
Kyoto protocol coverage of global aviation CO2 emissions
assuming no post-2004 growth
CO2 emissions covered (MMT)
Worldwide total Kyoto now
Source: ICCT, from data in SAGE Version 1.5 Global Aviation Emissions Inventories for 2000 through 2004.
What is the international community doing?
ICAO High Level Declaration (10/2009)
– 2% fuel efﬁciency improvement target to
– 2% “aspirational goal” 2020~2050
– Development of a CO2 standard for
new aircraft “types”
– Ultimately silent on the issue of
– Much interest in marine and aviation as
source of adaptation funding
– Reafﬁrmed intent to set CO2 standard
for new aircraft
– Work may be completed 2013 with
possible interim deliverables
Why an aircraft CO2 standard?
Traditional industry position: Aviation is fuel price sensitive
--> sufﬁcient driver for efﬁciency already
Evidence suggests room for improvement:
– Efﬁciency gains from new equipment declined markedly after 1990,
approximately ﬂat since 2000
– Large jet manufacturers slow to develop new single-aisle aircraft
– Race for speed and range impose efﬁciency penalty
– Under-optimization of aircraft to allow for general use (stage length,
belly freight capacity)
An aircraft CO2 standard, properly designed, can:
– Provide an incentive to deploy new technologies
– Minimize emissions vs. performance tradeoffs
– Promote increased optimization of aircraft to mission
– “Force” technology???
Lack of new designs driving stagnation
Average Age of Aircraft Manufacturer Production Lines, 1960-2008
Seat-km Fuel Burn (1960=100)
Age of Production Line (yr)
1960 1965 1970 1975 1980 1985 1990 1995 2000 2005
ICCT (2009). “Efficiency Trends for New Commercial Jet Aircraft, 1960 to 2008.”
Emissions and performance tradeoffs exist
Two ﬂight options, San Francisco to Italy
Estimated CO2 emissions (one-way)
SFO-ZRH-FLR (6100 miles): 969 kg CO2
SFO-JFK-PSA (6700 miles): 794 kg CO2
ICCT analysis, kayak.com and Piano-X model
Standard design issues
Metrics: How to measure/compare aircraft efﬁciency?
Applicability: cover all new aircraft or just new designs?
Thresholds: need to cover turboprops, BJs?
Certiﬁcation procedure: what is an aviation “duty cycle”
Stringency: How strict?
– Pass/fail at the aircraft level?
– Averaging within an aircraft family?
– Corporate averaging?
Criteria for cost/cost effectiveness
Certification test points matter
Relative block CO2 reductions at various operating points for
an historical narrowbody replacement
ICCT analysis using Piano-X model
Alternative compliance mechanisms important
for an aircraft CO2 standard
Efficiency standards enforced on a “pass/fail” basis tend not to raise
– “Pass/fail” used to regulate vehicle emissions, but rarely efficiency, and
only in developing markets with large gap between best and worst
– Sets up high stakes game where viability of particular models and even
manufacturers is on the line
– Favors “bottom scraper” rather than “top runner” standards
Need to think flexibly about alternatives to traditional certification
– Averaging within an aircraft family (commonality issue)
– Corporate average: set a single target for a manufacturer --> let
comply through means of their choice
– “Soft” (e.g. financial, etc.) penalties for non-compliance?
– Other ideas?
What can’t an aircraft CO2 standard do?
A standard cannot:
– Put a general price on aviation carbon
– Improve the efficiency of in-service aircraft
– Promote operational improvements in fuel burn (ATM,
– Address NOx, AIC impacts
Aircraft standard is only one part of a comprehensive
climate strategy for aviation
– Market-based measures
– Incentives for operational improvements
– Measures to address non-CO2 impacts of aviation
Non-CO2 climate impact may be the low hanging fruit
Normalized operating costs vs. normalized 100 yr global warming impact
for various designs of a narrowbody aircraft
Schwartz, E. and Kroo, I.M. Aircraft Design: Trading Cost and Climate Impact. AIAA 2009-1261.
Aviation climate challenge is a massive one that
requires new thinking
ICAO work on aircraft CO2 standard underway
Potentially, standards can:
– Speed technology deployment
– Manage emissions vs. performance tradeoffs
– Promote better optimization of aircraft to mission
Standard one part of a comprehensive strategy
– MBMs to price carbon
– Measures to improve operational efﬁciency
– Action on non-CO2 climate effects
ClimateWorks and Hewlett Foundations
Mazyar Zeinali, Fanta Kamakate, and
Drew Kodjak (ICCT)
CAEP WG3 colleagues