Lifecycle Carbon Footprint Calculation of Hand-Held Tool Propulsion Concepts

Following the recent trend in the automotive industry, hybrid and pure electric powertrain systems are more and more preferred over conventional combustion powertrain systems due to their significant potential to reduce greenhouse-gas emissions. Although electric powertrains do not produce direct emissions during their operational time, the indirect emissions over their whole life cycle have to be taken into consideration. In this direction, the carbon footprint due to the electrification of the hand-held power tool industry needs to be examined in the preliminary design phase. In this paper, after defining the carbon footprint calculation framework, assumptions and simplifications used for the calculations, a direct comparison of the total carbon dioxide equivalent (CO2eq) emissions of three equivalent power and range powertrain systems - a combustion-driven, a hybrid-driven, and a cordless electric-driven - is presented. The relative comparison of their life cycle CO2eq emissions delivers important insights for the future design considerations of hand-held power tools. Furthermore. as the energy storage system has the leading influence on CO2eq emissions for the hybrid and electric powertrains, a sensitivity analysis by examining different battery charging conditions and scenarios is presented. The aim of this study is to introduce useful knowledge of life cycle assessment for these small powertrains and forward an argumentation for different powertrain alternatives in the hand-held tool industry.