Fuel Consumption of Cars and Vans

Not on track
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In this report

Global average fuel consumption of new cars sold in 2017 improved only 0.7% year-on-year, slowing from the average 2005-16 improvement rate of 1.85% per year. To get on track with the SDS, which is aligned with the 2030 GFEI targets, annual improvements of 3.7% are needed. It is vital that standards become significantly more stringent and that vehicles comply with them in real-world driving conditions. Ambitious but achievable CO2 standards passed by the European Union and stricter standards in China inspire confidence, and rapid EV adoption will also help achieve efficiency goals.

Tracking progress

Average fuel consumption of new light-duty vehicles sold, 2005-17, and SDS trajectory to 2030

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Fuel consumption is most intuitively measured as the fuel required to travel a unit of distance (L/100km). Another common metric is fuel economy, which is the inverse of fuel consumption, or the distance travelled per one unit of fuel (e.g. km/L or MPG). This metric is calculated for each vehicle model through standardised testing procedures and drive cycles. Technologies that improve vehicle fuel efficiency are important for CO2 emission reductions because they enable the emission of less CO2 for the same amount of transport activity.

A vehicle’s fuel consumption is based primarily on its powertrain technology and size.

The vast majority of light-duty vehicles are equipped with gasoline-powered spark-ignition-engine powertrains, and they tend to have higher fuel consumption. Diesel engines consume 10-20% less fuel thanks to more efficient engine operations, whereas hybrid vehicles, usually powered by gasoline, have even lower fuel consumption because the engine almost always operates near peak efficiency and it accommodates some energy from regenerative braking. Electric vehicles have the lowest consumption (of course, pure battery EVs do not use liquid fuel at all) owing to the intrinsically higher efficiency of electric motors compared with ICEs.

Vehicle size, which is usually based on vehicle weight, generally determines fuel consumption: larger vehicles such as SUVs consume more energy than smaller, lighter vehicles on average. Fuel consumption of hybrid and electric vehicle depends less on their weight because they are able to recover a portion of the energy lost when breaking.

Vehicle fuel consumption as a function of weight for various powertrains, 2017

Fuel consumption Lge/100 km

Battery electric

Gasoline

Diesel

Hybrid

Plug-in hybrid

12

9

6

3

0

500

1125

1750

2375

3000

Empty weight (kg)

Vehicle fuel consumption as a function of weight for various powertrains, 2017

Fuel consumption Lge/100 km

Battery electric

Gasoline

Diesel

Hybrid

Plug-in hybrid

12

9

6

3

0

500

1125

1750

2375

3000

Empty weight (kg)

Vehicle fuel consumption as a function of weight for various powertrains, 2017

Gasoline

Diesel

Hybrid

Fuel consumption Lge/100 km

Battery electric

Plug-in hybrid

12

9

6

3

0

3000

1125

1750

2375

500

Empty weight (kg)

Notes: Lines show exponential correlation. The line gradients show that the dependency of fuel consumption on vehicle mass is much lower for electrified vehicles. The flatter the line, the lower the dependency. Fuel consumption has been normalised across test cycles. Source: IEA analysis based on IHS Markit (2018).

Rated fuel consumption – performance as measured in the testing facility – depends on the choice of drive cycle and testing procedure. Countries use different testing procedures, with each cycle designed, in theory, to better represent local driving patterns. Tracking the fuel economy of new LDVs sold worldwide requires that testing procedures and cycles be standardised, as modelled in the latest GFEI benchmarking report, which expresses values according to the NEDC, WLTC, EPA two-cycle and five-cycle, Indian Drive Cycle and JC08 national testing procedures.

There is much regional divergence in recent trends for average sales-weighted fuel consumption of newly sold LDVs. In the United States, average fuel consumption in 2018 had improved 0.8% from the previous year, reaching 9.4 L/100 km (according to the five-cycle EPA test), and preliminary figures indicate a further improvement of 1.6% in 2019.

In Europe, after 16 years of continuous improvement, fuel consumption worsened in 2017 and 2018, with estimates indicating it had risen to 5.1 L/100 km in 2018 (NEDC test). While no European data are available for 2019, powertrain sales shares at least suggest that fuel consumption did not continue to rise from 2018 to 2019. 

Despite ongoing efficiency improvements within each vehicle segment, consumer demand for larger vehicles has risen significantly. This trend is common to all vehicle markets and has led to a slackening – or in some cases even reversal – of national rates of fuel consumption improvements.

The worldwide market share of SUVs rose 15 percentage points between 2014 and 2019, to make up 40% of the global LDV market. Shares in North America and Australia were particularly high, around 50%. In addition to SUVs, pickup trucks – which tend to be even larger – also make up a significant share of sales in these markets.

Markets that traditionally have smaller vehicles, such as Europe and Japan, have also joined this global trend: in Europe 38% of new vehicles are SUVs, compared with 10% in 2010. The greatest market share growth has been in the small SUV segment, which includes many crossover versions of popular passenger cars. The average fuel consumption of a small SUV/pickup is more than 15% higher than for an average medium-sized car, for which market shares have fallen the most in recent years.

Share of SUVs in total car sales in key markets, 2010-2019

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In 2009, the European Union put in place a corporate average CO2 emissions standard that requires OEMs to reach target emission levels for cars sold within the European Union. With EU Regulation 2019/631, in April 2019 the European Council and the European Parliament approved new CO2 emissions standards for LDVs. The new targets are defined as percentage reductions in CO2 emissions per km from the baseline year 2021.

The targeted reduction for 2030 is 37.5% for cars and 31% for light commercial vehicles. This new goal builds on the previous requirement of maximum 95 gCO2/km of emissions for newly registered LDVs in 2020 and corresponds to 4.1 L/100 km for gasoline-powered vehicles (WLTC test) and 3.6 L/100km for diesel vehicles (WLTC test).

Each manufacturer therefore needs to ensure that the newly registered EU fleet’s average CO2 emissions per km remain within the limits by 2030, as penalties will be issued for noncompliance. To help OEMs meet the targets, selling EVs provides them with extra credits that make compliance easier by reducing the limit’s stringency by up to 5%.

The US EPA and NHTSA have finalised Part II of the Safer Affordable Fuel-Efficient Vehicles (SAFE) fuel economy and CO2 requirements for 2021‑26. The new SAFE rule, which was made law in March 2020, sets Corporate Average Fuel Economy (CAFE) and CO2 requirements for 2026-model vehicles at 5.82 L/100km1 (EPA two-cycle test) – an annual improvement of 1.5% from the 2020 level of 6.39 L/100km (EPA two-cycle test).

The SAFE rule drastically scales back the previous administration’s MY 2025 target of 4.31 L/100km (EPA two-cycle test), which would have required a 5% year-on-year improvement from 2017. Compliance pathways and flexibility options remain largely unchanged, but of particular concern is the phasing out of the credit multiplier for EVs and FCEVs after 2021 and for natural gas vehicles through 2026.

Given that Canada’s GHG emissions standards are linked to those set federally in the United States, the rollback of US CAFE standards directly affects the fuel economy of LDVs sold on the Canadian market. If Canada remains aligned with US standards, its required energy efficiency improvements will fall substantially – from 5% to 1.5% for model years 2021 to 2026.

In 2015, India adopted the two-phase implementation of corporate average fuel consumption (CAFC) regulations that include super credits for EVs, with a current target of 4.78 L/100 km for 2023 (Indian Driving Cycle test). As the average fuel consumption of new LDVs sold in 2018 was 5.5 L/100km (roughly 9% above the target for that year), the fleet was already only 7% away from meeting the 2023 target.

Compared with 4-5% annual CO2 reductions in other regions, India’s CAFC target translates into only 1.5% annually, which is lower than the 2.1% annual reductions it achieved during 2006-17.

China’s Phase V passenger car fuel consumption standards include a minimum weight-indexed fuel consumption rate per vehicle (ranging from 5.2 L/100 km to 11.9 L/100 km) and a fleetwide CAFC regulation. China’s CAFC targets have been progressively tightened by 30-40% with each phase from its Phase 3 limit of 6.5 L/100 km for 2015 to 5 L/100 km for 2020 under Phase 4234. Standards up to the present have been set using a modified NEDC testing procedure5.

The current Phase 4 standards incentivise electrified powertrains by granting credits: 1.5 credits for ultra-low fuel consumption vehicles; and 2-5 credits for NEVs (New Energy Vehicles) ─ EVs, PHEVs, and FCEVs (see the IEA Global EV Outlook 2020 for more details on these credits). NEV mandates are based on NEV credits (and not on sales targets) and are expressed as a percentage of total passenger car sales. The target for 2020 is 12% NEV credits, with a 2% increase every year to 18% in 2023.

Phase 5 of China’s CAFC published at the end of 2019 targets 4.0 L/100 km by 2025 (NEDC test). In this phase, both the targets and minimum fuel economy standards will be measured against the WLTC. Incentives for NEVs will also continue, albeit with modified coefficients.

In 2019, Japan approved a rule to tighten its fuel economy standards for LDVs through 2030 and shifted from using the JC08 to the WLTC testing procedure. The new standards require corporate average fuel efficiency of 3.95 L/100 km (WLTC test) by 2030, which implies an improvement of about 32% from average consumption in 2016 – or 2.9% average annual improvement. The new standards are set on a well-to-wheel basis to enable vehicle performance comparisons across powertrains, including for EVs.

Korea’s fuel economy standards have been in place since 2006. The target of 4.15 L/100 km (US two-cycle test) by 2020 was recently updated to 3.56 L/100 km (US two-cycle test) by 2030, which implies an annual average improvement of 1.4%.

In ASEAN countries,6 the sales-weighted fuel consumption7 of the LDV fleet was 7.3 L/100 km in 2015 (NEDC cycle). The ASEAN strategic road map envisions 5.4 L/100 km by 2025, which entails a 26% reduction in fuel consumption between 2016 and 2025, or an annual average improvement rate of 2.8% – a significant increase from historical improvements of 1.5% during 2005‑15.

Getting on track with the Sustainable Development Scenario (SDS) and achieving the 2030 GFEI target at the global level will require the widespread tightening of regulations to set ambitious but achievable fuel consumption reductions and/or mandate higher shares of efficient powertrains. Financial incentives are also needed to stimulate consumer demand for the best-performing vehicle technologies. 

There is a direct correlation between a country’s long-term fuel prices and the average fuel economy of the vehicles its citizens purchase. Morocco is one country that has successfully phased out road fuel subsidies in recent years, while others such as India, Mexico and Indonesia have been working on lifting them.

Globally, direct subsidies for road transport fuels are still in place in at least 38 countries, mostly developing ones. As these subsidies disincentivise the designing and marketing of efficient vehicle equipment, countries should reduce or remove them to reach the SDS goals by promoting the uptake of technologies that improve average fuel economy. 

Countries that do not subsidise road fuels but also do not levy taxes tend to have vehicles with 50% higher fuel consumption than countries where fuels are taxed. This is particularly true for developed countries with relatively low fuel prices such as the United States, Canada and Australia.

To reach the SDS targets, these countries should consider increasing fuel taxation to encourage the purchase of more efficient vehicles and thereby decrease road transport CO2 emissions.

While most new vehicle sales are covered by fuel economy regulations, there is still scope for some countries – especially in the developing world – to introduce fuel economy standards, as the ASEAN countries have done recently. These regulatory tools have been proven effective to introduce better engine and vehicle technologies into the market and to decrease fuel consumption, and they are needed now to put the world on track with the SDS goals. Furthermore, implementing fuel economy regulations would prevent developing countries from becoming dumping grounds for outdated vehicle technologies that are becoming uncompetitive or prohibited in their home markets.

When setting new standards, countries should aim to increase the rate of average fuel consumption improvement rather than keep it constant or decrease it. As new technologies become available and costs decrease, more ambitious targets become technically achievable.

The current market trend of greater average vehicle size and weight increases the cost of reducing fuel consumption. To curb or reverse this trend, governments could discourage the purchase of larger vehicles by enacting fuel economy standards in two ways. First, adopting footprint-based standards would encourage OEMs to decrease vehicle weight for a given footprint. Second, governments could set standards at a level that flattens the fuel economy curve, making it more difficult for heavier vehicles to comply.

In addition, “feebates”, which subsidise the purchase of the most fuel-efficient and lowest-polluting vehicles and tax the least-efficient and most-polluting ones (and can be designed as revenue-neutral so that the taxes completely finance the purchase subsidies), can effectively complement standards to hinder the trend of increasing vehicle size and weight.

Tightening the rules governing fuel consumption measurement during tests as well as standards to guarantee on-road-driving compliance are essential to ensure that all stakeholders take action to meet policy goals.

As the Dieselgate scandal so vividly demonstrated, it is possible for car manufacturers to comply with testing requirements even while selling vehicles that emit pollutants with serious health impacts in real-world driving conditions. The same applies to CO2 emissions, but there are ways to improve regulatory procedures to avoid this, as demonstrated by efforts to: (a) devise a more representative testing procedure that incorporates real-world driving emissions (the WLTP); and (b) monitor in-use emissions of local air pollutants (The Real Urban Emissions (TRUE) initiative). These systems must be scaled up and adopted by more countries, however, and always at the national level.

Resources
References
  1. The 2026 SAFE fuel economy and CO2 requirements by vehicle class are: cars = 4.93 L/100 km; and light trucks = 6.89 L/100 km. Both are measured using the EPA two-cycle test.

  2. MIIT (Ministry of Industry and Information Technology, China) (2011), GB 27999-2011 and GB19578-2004: Fuel consumption evaluation method and targets for passenger cars. Phase 3 standards, MIIT, Government of China.

  3. MIIT (2014), GB19578-2014 and GB27999-2014 Fuel consumption limits for passenger cars. Phase 4 standards, MIIT, Government of China.

  4. MIIT (2019), Phase 5 fuel consumption standards (GB 19578) and fuel consumption evaluation methods and targets for (GB 27999) passenger cars, MIIT, Government of China. 

  5. GIZ (Deutsche Gesellschaft für Internationale Zusammenarbeit GmbH) (2019), China transport policy briefing, The Periodical Update of GIZ in China, No. 5.

  6. Indonesia, Thailand, Singapore, Malaysia, the Philippines, Vietnam, Cambodia, Laos, Brunei and Myanmar (Burma).

  7. Estimated from LDV fleets in Thailand, Indonesia, Malaysia, the Philippines and Singapore, which combined account for 95% of the ASEAN LDV market.

  8. CA vs. Chao, Lawsuit challenging the National Highway Traffic Safety Administration's final rule preempting state regulation of carbon dioxide emissions from vehicles, 1:19-cv-02826 (D.D.C 2019), http://climatecasechart.com/case/california-v-chao/.

  9. EPA. (2020). The 2019 EPA Automotive Trends Report. Retrieved from https://www.epa.gov/automotive-trends/download-automotive-trends-report 

  10. GFEI. (2019). GFEI re-launch document. Retrieved from https://www.globalfueleconomy.org/data-and-research/publications/gfei-re-launch-document

  11. ICCT. (2019). Comments on China's proposed 2021-2025 fuel consumption limits, evaluation methods, and targets for passenger cars. Retrieved from https://theicct.org/news/comments-chinas-proposed-2021-2025-fuel-consumption-limits-evaluation-methods-and-targets 

  12. MoRTH (Ministry of Road Transport and Highways, India) (2018), Test Method, Testing Equipment and Related Procedures for Type Approval and Conformity of Production (COP) Testing of L2 Category Vehicles for Bharat Stage VI Emission Norms as per CMV Rules 115, 116 and 126, MoRTH, Government of India, New Delhi, https://morth.nic.in/sites/default/files/ASI/AUTOMOTIVE%20_INDUSTRY_STANDARD.pdf.

  13. MoRTH (2016), Notification G.S.R. 889 (E) of 12 September Regarding Implementation of Bharat Stage VI Norms for 2-, 3- and 4-Wheelers, The Gazette of India, Government of India, New Delhi, http://egazette.nic.in/WriteReadData/2016/171776.pdf.

  14. Motie. (2016). Realization of energy consumption structure of advanced countries in 2030 through energy efficiency innovation. Retrieved from http://www.motie.go.kr/motie/ne/presse/press2/bbs/bbsView.do?bbs_cd_n=81&bbs_seq_n=161993

  15. OECD. (2019). Update on recent progress in reform of inefficient fossil-fuel subsidies that encourage wasteful consumption. Retrieved from https://www.oecd.org/fossil-fuels/publication/OECD-IEA-G20-Fossil-Fuel-Subsidies-Reform-Update-2019.pdf

  16. Office of Attorney General Maura Healey (2020), AG Healey to sue Trump administration over rollback of clean car standards, press release, 31 March, Mass.gov., Commonwealth of Massachusetts, https://www.mass.gov/news/ag-healey-to-sue-trump-administration-over-rollback-of-clean-car-standards.

  17. Reuters (2020), China says no significant cut in new energy vehicle subsidies in 2020, https://www.reuters.com/article/us-china-autos/china-says-no-significant-cut-in-new-energy-vehicle-subsidies-in-2020-idUSKCN1ZA09Z.

  18. technode (2020), Electric vehicle subsides in China extended to 2022, https://technode.com/2020/04/02/electric-vehicle-subsides-in-china-extended-to-2022/.