As part of an online event, the DLG (German Agricultural Society) specialist center for agriculture, in cooperation with DLG Mitteilungen, focused on alternative drive concepts and fuels for agriculture. Experts from academia, product development, and agricultural practice presented the current state of development and discussed the advantages and disadvantages of various approaches.
Germany Aims to Reduce Greenhouse Gas Emissions by 65% by 2030
By 2030, Germany aims to reduce its greenhouse gas emissions by at least 65% compared to 1990 levels. The Climate Protection Act stipulates that annual emissions in agriculture must be reduced to 56 million tons of CO2 equivalents by 2030 through several binding interim steps. This goal is theoretically achievable, as only a 5% reduction is currently necessary to meet this limit. However, the situation is complicated by the fact that some of the emissions caused by agriculture are attributed to other sectors in the climate balance, meaning the actual reduction needed for greenhouse gas emissions may be significantly higher.
A frequently discussed approach in public discourse is the transition away from fossil fuels for vehicle propulsion. The focus is on moving away from gasoline and diesel toward alternatives such as electric mobility, driven by the ongoing transition in the passenger car sector as well as promising developments in on-road commercial vehicles.
Two-Hour Online Event by DLG
The main challenge in agriculture is the high power density in tractors, forage harvesters, combines, and similar machinery, which is why agricultural technology worldwide still predominantly relies on diesel engines and fossil fuels. However, the government is increasing pressure on the agricultural sector in Germany to transition quickly to more sustainable alternatives. For example, tax incentives for agricultural diesel are set to be eliminated in the future. Against this backdrop, manufacturers of agricultural machinery are under significant pressure to intensively engage with the topic of alternative drives. In addition to the agriculture and forestry machinery sector, industries such as manufacturers of commercial vehicles and construction machinery in both on-road and off-road heavy-duty segments are also affected.
To assess the current situation and explore potential solutions for the near, medium, and distant future, a two-hour online event was held where scientists, product developers from engine and agricultural technology manufacturers, and representatives from agricultural practice discussed these issues. The event, which took place on October 1, 2024, was organized by the DLG specialist center for agriculture in cooperation with DLG Mitteilungen. It targeted practitioners from agriculture and contract farming, members of machinery rings, employees from organizations and associations, students, and other interested parties, reaching a total of over 180 participants from across the agricultural sector and its surrounding community.
Opening of the Event
The event was opened by DLG Vice President Prof. Dr. Till Meinel from TH Köln, who outlined the key aspects of climate protection and sustainability in his introductory remarks. He called for a collaborative dialogue to increase the use of alternative drive concepts and fuels. It is essential to bring together knowledge and skills based on the DLG principle of a round table to find the best possible solutions for practice.
The moderation of the event was handled by Prof. Roger Stirnimann from the University of Agricultural, Forest and Food Sciences (HAFL), part of Bern University of Applied Sciences, who also leads the DLG's Technical Committee on “Vehicle Technology.”
Alternative Drive Concepts
What alternative drive concepts are available as substitutes for diesel, and which of these should be discussed? Which concepts have the potential to replace agricultural diesel in the short, medium, and long term?
Dr. Jens Grube from KTBL in Darmstadt introduced the topic and provided an overview of the political background that led to climate legislation. He presented the relevant alternative fuels for agriculture and assessed the state of development regarding their use and potential in various agricultural applications. He covered a range from pure vegetable oils to biodiesel, HVOs, CNG, LNG, hydrogen, and electricity. At this point, the uniqueness of electric drives became apparent; while they achieve significantly higher efficiencies, they currently require about 20 times the weight for energy storage compared to conventional fuels. According to him, it is primarily the power requirements in agriculture that lead to preferences for different fuels. High power demands, such as those for soil cultivation and harvesting, can currently only be met with energy-dense liquid fuels. In mid-range applications, methane may be suitable, while he sees electrification as a viable option for low power requirements in farm-related areas. By around 2045, he envisions a scenario where the complete reliance on fossil fuels could be replaced.
Dr. Markus Schwaderlapp from Deutz AG in Cologne addressed the electrification of agricultural machinery and examined its possibilities and limitations. Unlike individual transportation, a shift to alternative transport modes, such as public transport, is not feasible in agriculture, nor is widespread electrification. He compared the battery capacity and weight of a typical electric car with 75 kWh and 500 kg to that of a typical tractor, which would require 1,500 kWh, equating to about 10,000 kg. However, Schwaderlapp also broadened his discussion to the entire off-highway sector, warning against viewing electrification as a one-size-fits-all solution. He advocated for a range of tailored solutions in the off-highway sector to meet the diverse load profiles of various applications and customer requirements. He believes that there will still be a need for fuels alongside electricity.
Dr. Benno Pichlmaier from AGCO/Fendt also discussed the opportunities and limitations of electric drives in agricultural machinery. His focus included the efficiencies of different systems and the challenges related to energy storage for a full workday in the field. AGCO anticipates a wide spectrum and increasing diversity of drive technologies, starting with battery-electric drives in lower power segments, extending through hybrid drives and various renewable fuels, and ultimately including diesel vehicles in the high-performance range. In addition to the limitations mentioned for battery-electric drives, Pichlmaier noted that a hydrogen tank for a modern high-performance Fendt tractor would need a volume of approximately 6,500 liters, compared to a 450-liter diesel tank. Nevertheless, AGCO sees high potential in hydrogen and continues to conduct research and development in this area.
Broader Perspectives
Dr. Bouzid Seba from Liebherr contributed insights from the construction machinery sector. Here too, robust and durable drive solutions for harsh environments are in demand, with combustion engines powered by alternative fuels currently in focus. The construction sector is also experiencing an evolution of the powertrain, leading to a broader technology offering. Depending on the load profile of different machines and machine sizes, various alternatives are conceivable. In this context, tank strategy is gaining importance. Internally, Liebherr typically evaluates this based on the energy and power needs and the typical distance to refueling options.
Farmer Dr. Lars Fliege from the Agrargesellschaft Pfiffelbach highlighted the carbon footprint of his production processes while considering the practical requirements of his 5,000-hectare operation. He emphasized that in extraordinary situations like harvest time, any disruptions in operational chains are unacceptable across all machine sizes. For a battery-electric loader at the farm, refueling during work breaks might be feasible in practice; however, the additional costs of a fully electric loader compared to a combustion engine are currently unjustifiable. He sees a compromise with swap batteries in the mid-power range, as maximum operating times of five hours are often not exceeded. In particular, for maintenance or fertilization tasks, the tractor frequently returns to the farm and could swap batteries. He envisions gas-powered tractors primarily around biogas plants, especially those that are written off and no longer benefit from EEG subsidies. Regarding overarching goals and tasks for the industry, Fliege was quite clear in his remarks. He criticized the approach of measuring emissions at the exhaust and called for evaluating the CO2 balance from the production of machinery and fuel to their recycling. Additionally, he urged agriculture and society to rethink production processes concerning CO2 reduction, mentioning chemical plant protection, band drives, the elimination of rotary harrows, and the optimization of workflows. He also urged the government to create financial incentives for CO2 binding by farmers. Fliege believes that farmers could produce alternative fuels themselves and sees this as a potential new business area. He urged the government to provide innovative support for agriculture in this regard.
