Black smoke from the brewery chimney has caused consternation among some Dunedin residents, the Dunedin City Council and the Otago Regional Council.
But Lion Breweries capital projects manager Dave Butel said a new gas boiler meant black smoke was a thing of the past and only steam would be seen.
Four 32-year-old boilers had been pushed to their limit when the brewery took on production from the company's Christchurch brewery after that was damaged in the 2011 earthquake, Mr Butel said. The gas boiler from Dannevirke - installed four weeks ago - has taken over from the coal boilers, and yesterday two of them were removed.
The regional council last year warned Lion to sort out its emissions.
Mr Butel said Speight's was proud of its environmental management record, and the upgrades to the boiler and CO2 collection facilities would help improve its reputation.
Regional council resource management director Selva Selarajah said he was pleased the brewery had acted on concerns and confirmed the new boiler complied with council requirements.
The switch from the old to the new also meant production had improved ''sixfold'', Speight's operations manager Julia Hollis-Pye said.
The $29 million and ''north of that'' work was due to be complete by Christmas, and meant the premises would meet 76% of new building standards, Mr Butel said.
The project also included a brew house from Germany, 19 ''vessels'' in the new ''tank farm'' and the restoration of the 1876 building.
Although there was the option of moving to a bigger premises, Lion never really considered that because of the historic building, Mr Butel said.
Work is continuing on the restoration of the main cellar building, with the original signs now fully restored and the Rattray St front near completion.
Up to 80 contractors had been working at the site, and permanent jobs numbers had increased from 11 to 32 since the Christchurch earthquake.
Gas is supplied from Nova Energy in South Dunedin. Two of the old boilers seem destined for scrap. One has been given to the Dunedin Gasworks Museum, and one was bought by a neighbouring company.
