The warning comes amid mounting concerns about the way buildings of all shapes and sizes are designed.

Many designs simply do not consider what power bills end up being once a building starts operating, sustainability expert Ian McBurney says.

Business as usual approaches simply will not work, he says.

"We can't keep building buildings that are expensive to run, especially when budgets are tight. It adds to ongoing operational budgets forever," Mr McBurney said.

He pointed to Kangaroo Flat's new power-guzzling indoor pool, the Gurri Wanyarra Wellbeing Centre which helped drive the City of Greater Bendigo's carbon footprint up to 17,618 tonnes in 2018-19, nearly double that of the year before.

The council is yet to decide whether to install solar panels or a gas powered "co-generation" system capable of recycling emissions at the pool.

Both could help cut down on costs, both were considered before the council built the centre and neither have been installed.

The council decided to wait until it had been running for a year to get a better sense of how it would use power - something it has pointed out was recommended by the Office of the Victorian Government Architect.

But the decision has been criticised by some including the Bendigo Sustainability Group's president Trevor Smith.

"This (decision on solar panels) definitely should have been dealt with in the planning stage. It's pretty black and white to me," Mr Smith said.

He acknowledged that building projects often have limited budgets but was not convinced ratepayers saved money by spending less on the build, given power bills since the centre opened.

Mr McBurney said he did not highlight Gurri Wanyarra to bash the council.

"Too many organisations and people do this. It has to change," he said.

Mr McBurney is concerned that best intentions for sustainable features in government and private builds can be trumped by budget pressures as projects unfold.

"To get a building up you trumpet the sustainability features. When it comes to the capital budget stage you drop them off," he said.

That is not to say that the council did not go to any trouble to add sustainable features as it built Gurri Wanyarra.

A council document from 2016, before it was built, shows that the council planned 22 of them, not including solar panels or a co-generation system.

All but three ended up being built. The dropped items included openable windows installed in dry areas to provide ventilation and a viewing window to show efficiency measures in the plant room.

The final building also does not have a rainwater tank to flush toilets with, but technology has been installed to save 3000 litres of water used in pools every day, the council confirmed when asked about the list this week.

"Aquatic centres are known to be big consumers of energy and the utility consumption for the facility over the first 12 months was expected in this very large 5900 square meter building," active and healthy lifestyles manager Lincoln Fitzgerald said.

The council is now using data it collected about energy use to decide whether it will install solar panels or a co-generation plant.

The grounds for that decision were changing, Mr Fitzgerald said.

In 2016, the council was leaning towards a co-generation plant, believing it would take less time to pay off at 6.4 years than panels would at 10 years.

A report to councillors at that time suggested it would cost extra to make the roof strong enough to hold a solar grid large enough to help power the centre. It suggested allocating space for a co-generation plant and waiting to see what happened when the centre opened.

Now though, solar is back on the table.

It is becoming more appealing because panels are getting lighter thanks to technological breakthroughs, Mr Fitzgerald said.

The council is also cooling on a co-generation plant amid concerns about the spiralling cost of natural gas, he said.

Consultants have told the council it will need to find alternative energy sources for its pools and the Bendigo Art Gallery because producers are expecting significant drops in production in the coming five years.

Mr Fitzgerald also noted that the council is looking for ways to deal with its escalating carbon footprint with a major renewable energy deal.

The council has partnered with 42 others to ink a deal for green energy and believes it will be key in driving down its carbon emissions by three quarters.

Despite their concerns about solar panels at the pool, both Mr McBurney and Mr Smith welcomed the council's efforts on sustainable features used on the project.

Mr McBurney said perceived strengths and weaknesses of the pool's design process provided lessons for the Bendigo GovHub - a $90 million project currently being designed to house council staff as well as those from five state government departments in one building on Lyttleton Terrace.

The state government agency spearheading that project - Regional Development Victoria - has trumpeted the building's green credentials.

They include efficient indoor air quality systems, solar panels and water and energy monitoring systems.

Plans for that project are still to be finalised, a Victorian government spokesperson said when asked whether power bill costs had been factored in.

"It is our aim to ensure the project meets and exceeds where possible Australian sustainability standards," they said.

Other developers across Bendigo should also heed warnings not to try to save money on builds by passing costs on to building users, Mr McBurney said.

Bendigo's city centre is on the cusp of a "mini-rejuvenation" after landing more than $300 million for at least four projects in one section of the city centre.

New TAFE buildings, law courts and a rebuilt fire station are all being shaped by government agencies.

Private developers are also vying for planning permission to rebuild the Thomas Jewellers store in the Hargreaves Mall into a six-storey hotel.

The Hargreaves Mall Hotel project will have a number of sustainable features, according to an application before the council's planning department.

The project will meet council requirements for sustainability with a range of energy initiatives, a water tank and the use of building materials, developers said in their planning submission.

People building homes should also be thinking about future power bills long before they turn their first sod, Mr McBurney said.

They should also be prepared to spend a little more upfront to save themselves - or the people who buy their houses - more in the long term, he said.