Solar potential assessment of public bus routes for solar buses ...

Highlights
∼8.5% of electric demand can be offset by installing rooftop PV panels on electric buses.
Abstract
Current work investigates a method for evaluating the solar potential of public bus routes for solar electric buses. As access of solar radiation to roads is generally hindered by natural and man-made structures in the surroundings, the methodology involved taking several fisheye images along the chosen bus route. The visible sky and the structures were then separated using an automated image processing algorithm, also presented in this work. Then, these processed images were deployed in a solar assessment model to yield the weighted average yearly solar irradiation on the route. This was then compared with the energy requirements of an electric bus to see what fraction of its demand could be offset. For the case study, an existing public bus route in Invercargill (New Zealand) was analyzed. An appropriate fisheye camera was installed on the rooftop of a vehicle to obtain the images. It was found that installing solar panels on the rooftop of an electric bus may offset ∼8.5% of the electricity demand. This study will help councils (and/or bus contractors) to make decisions about moving to solar photovoltaic integrated electric buses, based on their designated routes.