Car Wars: Revenge of the SUV

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In 2015, transport became Scotland’s single largest source of greenhouse gas emissions. In 2018, Scottish transport produced emissions equivalent to 14.8 million tonnes of CO2 – just 0.5% lower than was produced in 1990.  By contrast, total Scottish greenhouse gas emissions fell by 45.5% over the same period. The biggest generator of Scottish transport emissions in 2018 were cars, accounting for 39% of total transport emissions.

Reducing greenhouse gas emissions from cars has been a key aim of Scottish Government climate policy since the publication of its first Report on Proposals and Policies, the previous name for the Climate Change Plan, in March 2011.  In anticipation of the publication of newest version of the Plan later this month, this post looks at these emission reduction goals, progress towards meeting them and wider trends in greenhouse gas emissions from cars.

Scottish Government greenhouse gas emission reduction targets

The first (2011) and second (2013) versions of the Report on Proposals and Policies stated that by 2020 there would be a mature market for low carbon cars in Scotland.  Average emissions from new cars registered in 2020 would be less than 95 grams of CO2equivalent per kilometre travelled (written as gCO2e/km). This milestone was supported by more detailed proposals set out in Switched On Scotland: A Roadmap to Widespread Adoption of Plug-in Vehicles (2013), in which 2020 was seen as the year when the market for plug-in vehicles would take off. 

The Climate Change Plan, effectively the third version of the Report on Proposals and Polices and published in February 2018, replaced this milestone with two policy outcomes and several “output indicators”, which measure progress towards achieving the policy outcomes, allowing the Scottish Government to determine whether implementation is on track.  These were: 

  • Policy outcome 1: Average emissions per kilometre of new cars and vans registered in Scotland to reduce in line with current and future EU/UK vehicle emission standards. The monitoring section included the following output indicators:
Year
2018
2019
2020
2021
Average emissions per kilometre for new cars, measured by grams of CO2equivalent per kilometre
107
103
99
95
  • Policy outcome 2: Proportion of new ultra-low emission cars (that is a car which emits less than 75g of CO2e/km) registered in Scotland annually to reach 100% by 2032.  The monitoring section included the following output indicators:
Year
2018
2019
2020
2021
Total % share of car sales that are classified as low emissions
2.1
3.6
4.7
6.1

The following sections go on to explore progress in meeting these policy outcomes and associated output indicators, which for brevity are simply referred to as “indicators”.

Average greenhouse gas emissions from new cars

In 2018, new cars registered in Scotland emitted an average of 123.6 grams of CO2 equivalent per kilometre travelled (gCO2e/km) .  This was 16.6gCO2e/km (15.5%) higher than the 2018 indicator set in the Climate Change Plan.  While Scottish figures for 2019 are not yet available, GB-wide figures show that average emissions from new cars registered that year had increased to 127.8gCO2e/km.  That is 24.8gCO2e/km (24%) higher than the 2019 indicator.

This increase in average emissions from newly registered cars appears to be the start of a trend, as illustrated in the chart below.  Average emissions from new cars have increased every year since 2016.   

Average greenhouse gas emissions from all cars registered in Scotland

As newer, less polluting cars have entered the vehicle fleet, average emissions of greenhouse gasses emitted per kilometre driven by car have fallen, as set out in the chart below. Between 2011 and 2018 the average level of emissions per kilometre driven in a car have fallen by approximately 15% (see Table 13.6b).

Total emissions from cars registered in Scotland

Total greenhouse gas emissions from cars registered in Scotland have increased since 2011, as set out in the chart below.  Cars registered in Scotland emitted 120,000 tonnes (2%) more CO2e in 2018 than 2011.

Ultra-low Emission Cars in Scotland

An ultra-low emission car is one which emits less than 75 grams of CO2 equivalent per kilometre travelled.  Typically, these are pure electric cars, hydrogen fuel cell cars and some plug-in hybrid cars. While the Climate Change Plan indicators relate solely to the annual proportion of new cars sold that fall within this definition, it is worth noting that there were 17,181 ultra-low emission cars registered in Scotland at the end of June 2020.  There were 2,524,477 cars registered in Scotland at the end of 2019 (the latest figures available), meaning ultra-low emission cars accounted for approximately 0.68% of all cars registered in Scotland in mid-2020. 

Sales of new cars

The most recent year for which detailed Scottish car sales figures are publicly available is 2018.  One hundred and eighty eight thousand new cars were registered in Scotland during 2018, 1.8% of which were classed as ultra-low emission.  That is 0.3% below the 2018 indicator of 2.1% of total car sales.  Although detailed 2019 sales figures for Scotland are not yet available, sales of ultra-low emission cars across Great Britain during 2019 accounted for 3.14% of all new registrations – 0.46% less than the 3.6% indicator for 2019. 

Analysis

Two significant, but linked, questions arise from the data set out above:

  1. Why have total emissions risen as the average level of emissions per kilometre driven by car have fallen?
  2. Why are average emissions from newly registered cars rising year-on-year, in direct contrast to national policy?

The first question can be answered, at least in part, by the fact that the total distance driven by car has continued to increase as average vehicle emissions have fallen, as set out in the chart below. 

Compared with 2011, during 2018 cars were driven an extra 2.8bn kilometres (8.4% more) in Scotland. A significant factor in this increase is that the number of cars on Scotland’s roads grew by 222,000 (9.4%) between 2011 and 2018.

The reasons behind the rise in average emissions from newly registered cars, in spite of policies aimed at reducing such emissions and encouraging the purchase of ultra-low emission cars, was explored by researchers at the UK Energy Research Centre in a Review of Energy Policy published in December 2019.  This highlighted that:

While attention has been directed towards the somewhat mislabelled ‘EV [Electric Vehicle] revolution’, we have failed to see what has been happening right in front of our eyes: the immense rise in sales of larger cars, particularly dual-purpose vehicles, known as Sport Utility Vehicles (SUVs). In 2018, SUVs accounted for 21.2% of new car sales, three times their share a decade earlier and up from 13.5% just three years earlier. SUV sales over the past four years totalled almost 1.8 million compared to a cumulative total of 47 thousand BEVs [Battery Electric Vehicles], a 37:1 ratio. SUVs emit about a quarter more CO2 than a medium-size car and nearly four times more than a medium sized BEV.

Over the last 10 years, Scottish Government climate and transport policy has failed to produce a reduction in total greenhouse gas emissions from cars.  Milestones, outputs and indicators set, and then revised, for the uptake of ultra-low emission cars and average emissions from new vehicles have been missed.  Given how significant cars are as a source of greenhouse gas emissions, the new Climate Change Plan, the National Transport Strategy 2 and Strategic Transport Projects Review 2 will have to quickly produce step changes in the uptake of ultra-low emission cars, significantly reduce demand for car travel and substantially increase the proportion of trips made on foot, by bike and public transport if emissions reduction targets are to be met.  The type and scale of the changes needed were touched upon by Professor Iain Docherty in evidence to the Rural Economy and Connectivity Committee in September 2020, where he indicated that:

…although people have begun to think about our recovery phase from the pandemic lasting until, perhaps, the end of 2021, that is only nine years before the date for the first decarbonisation target that the Scottish Government has adopted, which is 2030. In round terms, we know that we are going to have to do without roughly a third of our road vehicle fleet, even if the rest of it is completely emission free at the point of use, in order to meet those net zero targets.

Alan Rehfisch, Senior Researcher, Transport and Planning