Switching on auxiliary devices in vehicular fuel efficiency tests can help cut CO2 emissions by millions of tons

Journal Article
Switching on auxiliary devices in vehicular fuel efficiency tests can help cut CO2 emissions by millions of tons
Zhang, D., et al. (2021)
One Earth, 4, 135–145 (doi: 10.1016/j.oneear.2020.12.010)

Abstract/Summary:

Abstract: Enhancing automobile fuel efficiency is crucial to decarbonizing the transport sector. Recent studies have revealed a gap between real-world fuel efficiency and results from laboratory tests, where “off-cycle” auxiliary devices, like air conditioning (AC) systems, are not turned on. AC consumes the most energy among all off-cycle devices; however, the exact contribution of AC to fuel consumption remains unclear.

Here, by analyzing 1 million trip-level fuel efficiency records from China, we show that AC use when the temperature exceeds 25°C increases gasoline consumption annually by 1.3%. The amount differs across car models, with those produced by Chinese manufacturers showing relatively lower AC efficiency. Improving AC efficiency could cost-effectively reduce CO2 emissions by 1.6–2.4 million tons in China every year.

Therefore, we suggest integrating off-cycle devices into future fuel efficiency regulations, which will reveal the fuel efficiency gap, incentivize car manufacturers to develop high-efficiency devices, and further tap this emissions reduction potential.

Citation:

Zhang, D., et al. (2021): Switching on auxiliary devices in vehicular fuel efficiency tests can help cut CO2 emissions by millions of tons. One Earth, 4, 135–145 (doi: 10.1016/j.oneear.2020.12.010) (https://www.cell.com/one-earth/fulltext/S2590-3322(20)30656-4?_returnURL=https%3A//linkinghub.elsevier.com/retrieve/pii/S2590332220306564%3Fshowall%3Dtrue)
  • Journal Article
Switching on auxiliary devices in vehicular fuel efficiency tests can help cut CO2 emissions by millions of tons

Zhang, D., et al.

4, 135–145 (doi: 10.1016/j.oneear.2020.12.010)
2021

Abstract/Summary: 

Abstract: Enhancing automobile fuel efficiency is crucial to decarbonizing the transport sector. Recent studies have revealed a gap between real-world fuel efficiency and results from laboratory tests, where “off-cycle” auxiliary devices, like air conditioning (AC) systems, are not turned on. AC consumes the most energy among all off-cycle devices; however, the exact contribution of AC to fuel consumption remains unclear.

Here, by analyzing 1 million trip-level fuel efficiency records from China, we show that AC use when the temperature exceeds 25°C increases gasoline consumption annually by 1.3%. The amount differs across car models, with those produced by Chinese manufacturers showing relatively lower AC efficiency. Improving AC efficiency could cost-effectively reduce CO2 emissions by 1.6–2.4 million tons in China every year.

Therefore, we suggest integrating off-cycle devices into future fuel efficiency regulations, which will reveal the fuel efficiency gap, incentivize car manufacturers to develop high-efficiency devices, and further tap this emissions reduction potential.

Posted to public: 

Tuesday, February 16, 2021 - 15:11