Public buses fitted with ultra-thin solar panels started plying Singaporean roads on March 30 in a six-month proof-of-concept trial by bus operator Go-Ahead Singapore.

The panels are expected to help Go-Ahead Singapore save 1,400 litres of diesel per bus per year. (Photo: straitstimes.com)

The panels, which are 1.6 mm thick, flexible and shatterproof, were installed on the roof of two Man A22 Euro 6 diesel-powered buses. The buses are operated on service 15, which starts and ends at Pasir Ris Bus Interchange, in a trial that runs until September.

Weighing less than 20kg, the solar panels will supply 1,000 watts of power. This will be used to charge the battery on the buses, which would otherwise have to rely on the vehicle's alternator. This will in turn reduce the load on the engine.

The bus battery is typically used for ignition and to power components like lights and security cameras when the engine is turned off.

The panels are expected to help Go-Ahead Singapore save 1,400 litres of diesel per bus per year. This is about 3 to 4 percent of the fuel that is typically consumed by such diesel buses, and translates to a reduction of 3.7 tonnes of carbon emissions per bus per year.

The six-month trial aims to evaluate how effective the panels are in harnessing solar energy here and to ensure the panels can withstand the higher temperatures and daily washing of the buses.

The solar panel efficiency is expected to be higher in tropical Singapore, said Go-Ahead Singapore managing director Andrew Thompson.

Go-Ahead Singapore said the two buses with solar panels underwent rigorous safety assessments by the Land Transport Authority and are approved for public road trials.

The panels, which are at least three times thinner than some conventional solar panels, will be inspected weekly in the first two months. The operator will then do a review to determine the appropriate examination schedule.

Source: VNA