Energy Efficiency of Tunnel Boring Machines.

Abstract: Herrenknecht AG is a German world-leading Tunnel Boring Machines manufacturer showing strong awareness and concern regarding environmental issues. The company supports research on the Energy Efficiency (EE) of their products, aimed at the development of intelligent design for a green Tunnel Boring Machine. The aim of this project is to produce a ’status quo’ report on EE of three types of Tunnel Boring Machines (Hardrock, EPB and Mixshield TBM). In the framework of this research 39 projects are analysed using calculation tools, plotting and statistical functionalities of Excel and Matlab. The findings of this study inter alia confirm the existence of data quality issue and highlight the necessity of data quality control, allow identification of specific distinctions between energy consumption of the three investigated TBM types, and stress the necessity for optimisation of the layout of TBMs energy supply units and main consumers. Moreover the results of the survey suggest that there is a certain energy saving potential, which is achievable by e.g. an adequate selection of the machine type prior to start of a given project and better adjustment of the machines’ layout to the particular local geological environments. An EE implementation strategy, indicating further research needs, is suggested and discussed.