|Summary of CO2 emissions for BAU and Maximum Impact (MI ) scenarios. The MI scenario anticipates complete tailpipe decarbonization of road and rail. Click to enlarge.|
The entire UK transport sector could see a 76% reduction in CO2 emissions by 2050 compared with business-as-usual under a Maximum Impact (MI) scenario that applies all feasible interventions to achieve a “near zero
carbon” UK transport sector, according to a new study from researchers at the University of York and the Stockholm Environment Institute (SEI) York. Under the MI Scenario, road and rail are projected to become carbon neutral (rail via 100% electrification).
The recommended measures and assumptions to achieve the MI scenario are grouped into four areas: Spatial planning, Fiscal, Behavioral and Technology. With the first three categories, the report recommends specific policy actions designed to reduce demand or change high-consumption behavior, that in turn, can influence the technology end-points.
The authors note that the 76% reduction falls short of the zero carbon target, due entirely to CO2 emissions from aviation and shipping. However:
…the MI Scenario for road and rail transport depends on the decarbonisation of the electricity supply system. A detailed analysis of policy
pathways leading to such a decarbonised electricity supply in the UK is outside the scope of this study. However, if the electrical power sector decarbonisation
by 2050 is less than 100 per cent, CO2 emissions from
road and rail transport will be substantially higher than
projected for the MI Scenario.
—“Towards a Zero Carbon Vision for UK Transport”
Road transport. The report outlines measures under each of the four main areas to bring road transport CO2 emissions down to zero.
Measures for Spatial Planning include:
- Pedestrian-oriented design: urban car VKT
reduced by 10%.
- Road space reallocation: urban car CO2
emissions reduced by 11%.
- High occupancy only vehicle (HOV) lanes:
urban car VKT reduced by 1.4%.
- Compact development: for cities >100K
population, all traffic VKT reduced by 30%.
- Regional co-operation model for HGVs:
assume 50% reduction in total VKT.
Fiscal assumptions include:
Road user charges resulting in a 3% reduction in all
Workplace car parking charges: CO2 emissions
from commuting by car reduced by 12%. Thus, assuming 25% of
total car CO2 emissions are due to commuting, this equates to a 3% reduction in total passenger car CO2
Urban, non-commuting car parking charges: A 13% reduction in urban car VKT assuming: (a) VKT elasticity factor of -0.07; (b) 75% of car CO2 emissions are for non-commuting purposes assuming that this also applies to urban car use;
and (c) average parking charges increase in real
terms by 10% per annum from 2010 to
2030, to give a 570% final increase.
Fuel price: A 5% per annum fuel price
escalator is introduced from 2010 onwards producing a 600% fuel price increase by
2050 for all road vehicles. A short-term elasticity
factor of -0.25 for fuel consumption applied annually results in a 40 per
cent reduction in CO2 emissions for all fossil
fuel powered road vehicles by 2050. (An implicit
assumption here is that there will be progressive
availability of non-CO2 emitting alternatives such
as electric vehicles powered by carbon neutral
electricity, and carbon neutral public transport
VED circulation tax: Increased differentiation
reduces VKT for all cars by 4.8%.
Car purchase tax and ‘Feebate’ systems based on
fuel consumption: Reduces VKT for all cars by 4%.
Public transport fares subsidy: a 30%
reduction in fares will reduce CO2 emissions for
all cars by 2%.
Requisite Behavioral changes include:
- Ecological driving: 8% reduction in car
- Reducing motorway speed limit to 60 mph and
enforcing it: 10% reduction in motorway
- Car share: reduction in car VKT for urban (8.3%) and rural (3.6%) driving.
- Modal shift for road freight: 20% reduction
in CO2 emissions from HGVs.
The assumptions in the MI Technology package differ from the prior three in that they represent desired technology end-points rather than a set of policy prescriptions. The end-points include:
All passenger cars, LDVs, motorcycles and
HGVs/buses less than 12 tonnes in weight to be
plug-in electric vehicles (PEV) using 100% renewable electricity or
hydrogen fuel cell powered (using carbon neutral
Heavier HGVs and buses/coaches (>12 tonnes)
to be powered by either H2 fuel cells (with carbon
neutral sourced hydrogen) or sustainable biofuel.
Liquefied petroleum gas (LPG) vehicles
completely phased out.
These technology end-points
could arise simply as a result of the spatial, fiscal and
behavioural measures described earlier. In particular, the
fiscal measures alone may render petrol/diesel powered
vehicles prohibitively expensive compared with say,
PEVs. Alternatively, a society being adversely affected
by climate change in forty years time may reasonably
decide to ban any remaining petrol/diesel vehicles
completely. In this case the technology assumptions
would in a sense, also represent policy interventions.
Of course, significant policy interventions would be
required to produce the carbon neutral UK electricity
power generation sector on which the above assumptions
are based, but a detailed analysis of these is beyond the
scope of this study.
“Towards a Zero Carbon Vision for UK Transport”
The results of this research and the clear policy recommendations have been sent to the Minister of Transport and the Minister responsible for climate change policy, the Chairs of the Regeneration and Transport Board and Environment Board of the Local Government Association, the AA and RAC, the Association of Train Operating Companies, the bus industry, the British Shipping Council, British Airways, Easyjet and Ryanair, BAA and the Freight Transport Association.