Comparison of Connection Possibilities for Powering Zero-Emissions Construction Sites from Traction Grids

Abstract

This paper investigates the feasibility of supplying zero-emissions construction sites directly from traction grids using the metro of Amsterdam, The Netherlands, as a case study. Three construction site sizes are investigated in this paper for either an AC or a DC-side connection and for either a daytime or nighttime energy supply. It is concluded that AC side connections are cheaper, more predictable, and have an abundance of commercial power electronics and protection solutions compared to the DC-side connection, yet they do not allow the harvesting of braking energy, and they can breach the AC grid energy contract limits. Meanwhile, DC side connections have recovered over 25% of the small construction site demand and 18% for medium and large ones from the otherwise-wasted braking energy of the public transport fleet.However, still no solution in this paper is found to be better than the previously investigated construction site mobile batteries, which can supply even the large sites with over a third of their energy from braking energy and offer both the public transport and construction site operators all the benefits of controllability, on-site charging, and logistical flexibility.