The Welsh Government's official fleet has just one electric car, despite being the first UK parliament to declare a ''climate emergency''.
Out of 77 official cars used by the Welsh Government, 95% of those in operation are diesel.
While diesel cars produce less CO2 than petrol cars, exhausts can emit damaging pollutants like nitrogen oxide.
According to the RAC, the newer the diesel, the less damaging it will be to our environment, though how much they emit can be dependent on real world driving - tests that measure the pollutants a car produces while being driven on real roads.
In May, the Welsh Government committed to reach net-zero greenhouse gas emissions by 2050.
Speaking after the announcement, Minister for Environment, Energy and Rural Affairs, Lesley Griffiths said tackling climate change required ''collective action and the government has a central role to making that collective action possible.''
Plaid Cymru's Shadow Minister for Environment and Rural Affairs, Llyr Gruffydd AM described the statistics as ''astonishing.''
In figures obtained by a Freedom of Information request, trips made by official cars to deliver documents increased by nearly 50% in the last financial year.
In response to the findings, a Welsh Government spokesperson said the majority of these are "commercial vehicles used for highway maintenance and by traffic officers and our marine and fishery patrols."
They added the government has "significantly reduced the environmental impact of our fleet over the past 10 years and recently added an electric vehicle to our official car pool of 12 vehicles."
"We will continue to do everything we can to reduce the environmental impact of our fleet whilst providing value for money for the taxpayer."