A senior councillor has questioned whether Dorset Council's level of spending on projects linked to climate and ecological change can be justified.

Swanage councillor Bill Trite admitted that his challenge was likely to be unpopular – his comment being met with an immediate defence from council leader Spencer Flower.

Cllr Trite said that with the UK as a whole only contributed less than one per cent to global carbon emissions, and the tiny amount Dorset was likely to be able to save was negligible.

"We need to consider this in context… if all our expenditure on attempts to deal with our emissions were successful tomorrow and our emissions became zero tomorrow – globally it would make next to no difference," he said.

"I'm emphatically not a climate change denier but it's against this, less than one per cent, that our expenditure, all expenditure in this area, should be assessed and justified. I don't think it ever is.

"Don't you think it should be assessed and justified with respect to that less than one percent context?"

"I'm reflecting what people have said to me. By not even mentioning it, it does make us look as if we are trying to avoid something that might not be to our advantage, that's how it come across to some people, because there's a lot of money being spent.

"This global context is always avoided. You can say we're just following government directions, nevertheless I think it does need to be justified if we want people to have confidence in what we are spending that money on."

Council leader Cllr Spencer Flower said the council's work on climate and ecological change was entirely justified – resulting in savings for council taxpayers, a cleaner environment and helping to protect the health of local people.

He said it was also important that Dorset Council set an example on climate to the people of Dorset which he hoped others would follow.

"We shouldn't be shy about what we are achieving," he said.

"We should put a bit more of a narrative around about the importance we have attached to climate change and how it reflects in our budget."

Weymouth's Green councillor Brian Heatley had earlier asked for greater transparency about the council's spending on climate, claiming that some of it is not easily identifiable in budget figures and cannot easily be separated from other spending across a range of departments.

"I do think we should be producing some kind of account about what climate change work is costing us on the revenue side which estimates what those costs and benefits are across the organisation," he said.

"This is partly a matter of transparency – to be honest to the world what it is costing."

The funding identified includes a five-year £10million capital spending programme for projects linked to the environment and climate change.

Figures are also shown for a small staff team, costing £169,000 a year, which deals with the council's approach to the climate and ecological emergency it declared at its first meeting more than three years ago.

In the current financial year, the council has spent about £19million on making about 200 public buildings more energy efficient, mainly through solar power, low energy lighting and insulation, with another £2.7million to provide electric vehicle charge points.

Both amounts were grants and have not come out of payments from Dorset council taxpayers, although a relatively small amount of staff time will have been involved.

About £17million has also been achieved by Low Carbon Dorset on a range of projects, largely funded by European money which is now at an end, although other funding streams are being explored for the team to continue its work.

Corporate director for climate and ecology, Steven Ford, told councillors that if the authority's good progress on climate so far was to continue, all of its services would have to be "re-aligned" in the way they operate to make fundamental changes to reduce carbon emissions.

Environment portfolio holder Cllr Ray Bryan said he would like to see more council vehicles not running on fossil fuels, but admitted that the technology was not yet ready for larger vehicles such as refuse lorries, which were likely to be powered by hydrogen when they become available, with a hydrogen production plant already based locally at Canford.

The meeting heard that the council already had a small number of electric vehicles (10), with 14 more on order when existing vehicles come to the end of their working life.

Mr Ford said that energy saving measures already introduced could "soften" the upward curve of energy costs by £1million in the coming year.

The council is currently generating around 5MW of power from its own solar panels and is looking at ways of retaining at least some of it in battery storage rather than feeding into the national grid.