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The objectives of this research were to develop simulation models for agricultural tractors with different powertrain technologies and evaluate the energy consumption in typical agricultural operations. Simulation models were developed for conventional, parallel hybrid electric, series hybrid electric, fuel cell hybrid, and battery electric powertrains. Autonomie vehicle simulation software (version 2022) was used for the simulations and the tractor models were simulated in two tilling cycles and in a road transport cycle with a trailer. The alternative powertrains were configured to have at least the same tractive performance as the conventional, diesel engine-powered tractor model. The simulation results showed that the potential of the parallel and series hybrid powertrains to improve energy efficiency depends heavily on the tractor size and the operating cycle conditions. The fuel cell hybrid and battery electric powertrains have a higher potential to reduce energy consumption and emissions but still have inherent technical challenges for practical operation. The battery-powered electric tractor would require improvements in the storage energy density to have a comparable operational performance in comparison to other powertrains. The fuel cell hybrid tractor already provided an adequate operating performance but the availability of hydrogen and refueling infrastructure could be challenging to resolve in the farming context. [ABSTRACT FROM AUTHOR]

Highlights: [•] Capital and battery costs are important for hybrid and electric city buses. [•] Plug-in hybrid and electric buses have the best potential for high cost efficiency. [•] Fleet operation has significant effects on the cost efficiency of city buses. [•] Hybrid and electric city buses reduce energy consumption and emissions. [ABSTRACT FROM AUTHOR]

The objective of this paper is to evaluate technical requirements for electrochemical energy storage systems (ESSs) in hybrid mining loaders. These requirements take into account power and energy capacity, costs, life cycle, and safety-related requirements. The evaluation of the requirements is based on the characteristics of the current energy storage technology and vehicle simulation results. The evaluation shows that lithium-based batteries offer sufficient power and energy capacity; meanwhile, the requirements for cost and cycle life durability are dependent on the operating strategy and configuration of the loader. In particular, the power-intensive duty cycle of a mining loader can be challenging for batteries in terms of cycle life and thermal management. [ABSTRACT FROM PUBLISHER]

Uncertainty in operation factors, such as the weather and driving behavior, makes it difficult to accurately predict the energy consumption of electric buses. As the consumption varies, the dimensioning of the battery capacity and charging systems is challenging and requires a dedicated decision-making process. To investigate the impact of uncertainty, six electric buses were measured in three routes with an Internet of Things (IoT) system from February 2016 to December 2017 in southern Finland in real operation conditions. The measurement results were thoroughly analyzed and the operation factors that caused variation in the energy consumption and internal resistance of the battery were studied in detail. The average energy consumption was 0.78 kWh/km and the consumption varied by more than 1 kWh/km between trips. Furthermore, consumption was 15% lower on a suburban route than on city routes. The energy consumption was mostly influenced by the ambient temperature, driving behavior, and route characteristics. The internal resistance varied mainly as a result of changes in the battery temperature and charging current. The energy consumption was predicted with above 75% accuracy with a linear model. The operation factors were correlated and a novel second-order normalization method was introduced to improve the interpretation of the results. The presented models and analyses can be integrated to powertrain and charging system design, as well as schedule planning. [ABSTRACT FROM AUTHOR]