Thousands of tonnes of black bag waste in Swansea is being carted away from the city and incinerated to generate power, including in Cardiff and Sweden.
Non-recyclable waste produced by householders has for decades ended up at Tir John landfill site, Port Tennant, but it stopped accepting it last month for good.
The council has confirmed it has now signed contracts with two companies, Derwen Recycling Ltd and Geminor Ltd, to process the black bag waste.
In Derwen Recycling's case, this involves removing recyclable items from black bags and then sending the remainder as a fuel to be burned in "energy from waste" power plants.
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"This is a major step forward for the city in terms of how it disposes of non-recyclable waste," said Cllr Mark Thomas, cabinet member for environmental enhancement and infrastructure management.
"Most other councils in Wales are using energy from waste and so we are pleased to have now made the switch.
"Importantly, this means we are no longer burying tonnes of black bag waste in a hole in the ground now. This is something that residents in communities near to the old landfill site as well as across the city, will welcome."
The council recycled or composted 72,000 tonnes of waste from householders and businesses it collects from in 2020-21.
It landfilled a further 35,500 tonnes at Tir John, while 4,000 tonnes ended up at energy from waste facilities.
Stuart Hanford, director at Derwen Recycling, said it had been working with Swansea Council and other local authorities for years to help them meet landfill diversion targets.
The company removes hardcore, wood, plastic, aluminium and cardboard from construction waste and householder rubbish at its Neath Abbey base.
It also handles bulky waste, like mattresses and furniture.
The stuff that can't be recycled is converted into what is known as refuse derived fuel.
This refuse derived fuel is then sent to energy from waste plants to generate power, including the Viridor facility in Cardiff and three plants in Sweden.
Mr Hanford said the Sweden-bound fuel was shipped in containers which had transported paper and timber products from Sweden and would otherwise be empty on their return leg.
"I think Swansea are being very forward-looking," he said.
Geminor's UK base is in Staffordshire. It operates in several European countries. According to its website, it deals with around 600,000 tonnes of refuse derived fuel annually.
Swansea Council's message to residents and businesses is to keep separating their plastic, cans, bottles, paper, cardboard and food waste as much as possible because councils need to hit ever-increasing recycling targets.
Cllr Thomas said: "Switching over to a better way of disposing of black bag waste shouldn’t give residents the opportunity to recycle less."
Meanwhile, work is expected to continue for years to cap areas of dumped rubbish at Tir John and restore the land.
Around two million tonnes of rubbish is buried there.
The council is planning to build a solar farm on part of the site and has allocated £2.2 million towards the project for the 2022-23 financial year.
The Local Democracy Reporting Service has previously spoken to residents in Port Tennant and campaigners who were worried about what was going on at Tir John in the past.
One of them, Pamela Mock, of Danygraig Road, said: "I won't be sorry to see it close."
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