Transport Scotland and Energy Saving Trust are set to end taxi modernization grants in just two weeks.
Modernization experts say there is no further news on future rounds of funding to help drivers make their taxi engines cleaner and meet EURO 6 emission levels.
The Scottish Government introduced the new fund in 2019 to help commercial organisations, including taxi drivers, impacted by the introduction of low emission zones.
A spokesperson for Cybrand, a UK refurbishment and emissions solutions company, warned: “We heard this morning that funding for Euro 6 refurbishment in Scotland will close to new applicants on February 21.
“No news at this time if there will be further rounds of funding.”
Several major councils across England and Scotland have and continue to offer grants to taxi drivers wishing to upgrade taxis.
Taxi drivers could switch to greener taxis for as little as £1,300 in some towns.
Besides purchasing a new Zero Emissions Capability (ZEC) taxi, upgrading existing cabs to meet Euro 6 compliance standards is seen as a way to eliminate daily charges and future-proof licensed taxis.
The accreditation required to be exempt from emission zone charges in the LEZ or CAZ is known as the Clean Vehicle Retrofit Accreditation Scheme (CVRAS) and is administered by the Energy Saving Trust. Cybrand is the only approved installer with this certification able to offer a retrofit conversion on taxis that does not involve a completely new engine.
On a Euro 5 compliant taxi, the exhaust gases from the turbocharger pass directly into the combined catalytic converter and diesel particulate filter and from there through the silencer to the tailpipe.
On a retrofitted Euro 6 compliant cab, a new Selective Catalytic Reduction (SCR) system is installed in the exhaust system further downstream. This incorporates a thermoelectric element that helps bring the exhaust to an ideal temperature to promote efficient catalytic conversion. With the introduction of AdBlue, which is a diesel exhaust fluid, the SCR system reduces NOx to levels that exceed Euro 6 requirements.
SCR is beneficial as it reduces NOx by up to 90% and is one of the most cost effective and fuel efficient technologies available.