Controlling idling: a ready-made solution for reducing exhaust emissions from agricultural tractors

Mechanised agriculture accounts for nearly 70 million tonnes of CO2 emissions annually. To mitigate these CO2 emissions, powertrains running on alternative fuels and hybrid powertrains are under development. However, such solutions have not yet reached the technical maturity required for the marketplace. To make significant progress, considering the pressure imposed by the European Commission and others, ready-made solutions must be deployed to achieve rapid and large-scale reductions of greenhouse gas emissions. One such solution is to reduce unnecessary engine idling. This paper presents an investigation of the duration of idling stops, the energy required for starting the engine, and the time at which the engine should be turned off to avoid higher emissions from continued idling. Four tractors with different engine displacements were used in experiments. For the tractors, the energy required for engine start-up was measured and real-world data were collected over several months. From data analysis, it was found that shutting off the engines for idling stops longer than 4.4 s resulted in lower emissions. The four tractors showed different idling patterns; turning off the engine during unnecessary idling stops led to fuel savings of 1.1%–5.1%. Based on these results, 770,000 tonnes of CO2 annually could be saved by equipping tractors with the proper technology for turning off the engine during unnecessary idling stops.