21.06.2022

Meeting the environmental challenge

An independent study has evaluated the ideal power sources for mobile cranes - now and for the longer term.

Most manufacturers are of course striving to make their new products more environmentally friendly especially when it comes to how they are powered, driven by growing demand from end users. While battery electric is now feasible for most aerial work platforms and small telehandlers, the same is not true - at least not yet - for larger road going mobile cranes and larger telehandlers.

In order to obtain a definitive take on what power sources and fuel provides the lowest environmental impact, Liebherr commissioned Frontier Economics - one of Europe’s largest economic consultancies - to conduct a life cycle analysis of the greenhouse gas emissions of typical construction machines equipped with various drive technologies.

Frontier is a consultancy with a difference. Founded in 1999 it is wholly owned by its 326 employees working across 60 countries from offices in Berlin, Brussels, Cologne, Dublin, London, Madrid and Paris. The full study, which involved a number of experts from different fields, looked at how much CO2 is generated by a machine from its production and operation right the way though to recycling. The aim of the analysis was to comprehensively calculate the emissions of three types of machine - wheeled loaders, truck mixers and mobile cranes.

Stephen Albrecht of Liebherr International said: “Emissions analyses are generally limited to the operating phase. This is not enough for our products because greenhouse gas emissions also occur in the upstream and downstream phases of construction machines’ lifecycle. To get a complete picture, we examined all stages of the life cycle, including the production of energy and provision of the infrastructure. These results are combined in a so-called product carbon footprint, which describes the emissions of a product throughout the entire life cycle.”

The study indicated that for truck mixers, electric drives makes the biggest contribution to emission reductions, provided they use 100 percent renewable electricity for charging. The same applied to most wheeled loaders, but when it came to mobile cranes it showed that the use of HVO (Hydrotreated Vegetable Oil) offered the greatest savings potential. However, it is important to note, that the HVO needs to be certified as produced from plant and food waste, and in particular does not contain palm oil.

Over the longer term the study found that hydrogen made from CO2 neutral sources looks like the optimal solution, however, until the required hydrogen infrastructure and drive technologies have matured, HVO pushes it into second place, but only as an interim technology, particularly in existing fleets with combustion engines.

“The results of the life cycle analysis show that there is no uniform solution for climate neutral drives for construction machines,” added Albrecht. "A wheel loader on an urban construction site for example, is exposed to different conditions than a mobile crane used in the construction of wind turbines. The former can often be powered by electricity. In contrast, infrastructure projects in rural areas often lack the necessary power supply for an electrical connection. In addition, more energy is often required than can be provided with a battery operated electric drive."

The company concluded that for the moment HVO is of most interest, because it is already available, and has the advantage that it can be used in older diesel powered equipment, including developing markets.