The Scottish Government has announced £1.6 million of funding to reduce emissions from buses.
It is the first phase of the Bus Emissions Abatement Retrofit Programme (BEAR), an open competition delivered through the Energy Saving Trust.
It will support bus operators with the financial costs associated with exhaust retrofit kits, which aims to reduce nitrogen dioxide emissions from older buses and achieve the Euro VI emissions standard.
The air quality performance of the buses will also be monitored, with up to £25,000 per bus being provided.
Scottish Transport Minister Humza Yousaf said: “Many bus operators have already taken advantage of the previous seven rounds of the Scottish Green Bus Fund, where over £16 million of funding has resulted in over 360 new low emission vehicles being brought into the fleet.
“For many operators, the right decision is also to invest in retrofit technology for their existing fleet. This will breathe new life into older buses, reduce harmful nitrogen dioxide emissions and help to progressively improve the quality of the air in our towns and cities.”