Council bosses are starting trials which will see Perth bin lorries run on vegetable oil instead of diesel.
The three-month scheme will involve six vehicles.
If it proves a success, the method could be widened out through the Perth and Kinross Council fleet.
Backers hope it will help to reduce the local authority’s carbon emissions.
A bin lorry powered on diesel emits around 31 tonnes of CO² per year.
Switching to hydrotreated vegetable oil (HVO) could lead to a 90% reduction.
The HVOÂ fuel trial was approved in February.
Councillors had hoped it would start straight away, but it has taken until now for the preparations to be completed.
Groundwork in place for trial
Perth councillor Liz Barrett is vice-convener of the climate change and sustainability committee.
She said: “Further work was needed to change the fuel tanks pipes to ensure clear separation of HVO and diesel, before the fuel was ordered and delivered.
“This has delayed the very welcome start of the trial of HVO fuel in six vehicles.
“If it’s successful – as we expect – I look forward to it being rolled out to more of the fleet.”
HVO refers to fuels derived from sources such as rapeseed oil and waste cooking oil.
Supporters say it also produces fewer contaminants than traditional fuels.
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