The Ramsey County Board gave a boost Tuesday to St. Paul’s hopes for expanded recycling, agreeing to cover half the city’s projected ​$4.7 million cost for wheeled and lidded carts next year.

On a vote of 4 to 1, commissioners approved subsidies for municipally owned recycling carts that would either pay as much as 50 percent of the cost or $100,000, whichever is greater.

To accommodate expected demand, they also directed that $3.5 million be transferred from the county’s solid waste fund into the Public Entities Innovation Grants program, set up three years ago to help cities and school districts increase recycling.

Although all county municipalities are eligible for funding, the biggest beneficiary will be St. Paul. The city is asking the county for $2.68 million to buy 87,000 carts, most of them of the 96-gallon variety into which residents can deposit recyclables without having to sort them.

Mayor Chris Coleman had hoped to include the carts in this year’s budget, as part of a campaign to raise St. Paul’s recycling rates by making it easier to do. Minneapolis introduced the carts in 2013, and Maplewood did the same last year.

But the mayor thought better of it when officials projected that the carts would raise St. Paul’s recycling fees by one third, or about $17 more per household. That would have come on top of the city’s hike in the property tax levy.

In a letter to the county, St. Paul Public Works Director Kathy Lantry wrote that “your assistance will help us smooth these new costs so that the customers that we serve will not see unnecessary rate spikes and increases in their annual recycling fees.”

The city wants to begin using the carts in 2017, when it also hopes to have a new recycling contract in place. Officials are seeking bids from providers to replace the current contract with nonprofit Eureka Recycling, which expires in 2017.

Commissioner Janice Rettman, who represents several St. Paul neighborhoods, objected to funding the carts with money from the solid waste fund — which was at $22 million at the end of last year — and voted against the resolution. She said the original idea was to fund recycling carts for parks, not residential use.

But Ramsey County’s solid waste master plan seeks to hold municipalities more responsible for recycling, and the county has set a 75 percent recycling goal by 2030. It already has helped at least a few cities with cart purchases.

“It’s a good deal for residents … and it will improve recycling,” Commissioner Victoria Reinhardt said.

Coleman announced in 2013 a new effort to boost St. Paul’s recycling rates that involved expanding the number of accepted products and making recycling more convenient.

The city’s program now accepts many plastics it had previously rejected and uses a single-sort system, making it unnecessary for residents to separate newspapers, cans, bottles and other recyclables into different bins.