Gov. Kathy Hochul celebrated the completion of the Champlain Hudson Power Express on Tuesday, but New York City has received very little juice from the new transmission line since it was connected earlier this month.

The $6 billion project brings hydropower 339 miles from Quebec to New York City. Five-inch diameter cables buried underneath Lake Champlain and the Hudson, Harlem and East rivers are bringing power to a converter station in Astoria, Queens.

Hochul said the project is vital for meeting increased demand during the hottest season of the year.

“ This is not just a power line, this is a lifeline. This is a lifeline for thousands of homes and businesses and individuals, a million homes across the City of New York,” Hochul said at a press conference in Astoria.

But since the switch was flipped on June 1, not much power has flowed through the lines. According to the New York Independent System Operator, there was 24-hour power flow on the first two days of the month, but by the third day, that dwindled to five minutes until it dropped off to zero power flow between June 4 and 10.

Since then, the transmission lines have not offered full capacity.

Energy provider Hydro-Québec said the issue is in the details of the contract. The official contract started in June, but the Canadian company said it can’t fully power the line until July because of payment rules laid out by the NYISO. It should be resolved by July, said Lynn St-Laurent, a spokesperson for Hydro-Québec.

NYISO requires energy providers to bid out supplies more than a month in advance. The transmission lines weren’t completed until mid-May, which meant Hydro-Québec could not get the full contract price for electricity before July. This means that Hydro-Québec could get as little as half the price for its power unless it’s during a time of high demand.

“Were only able to get a small part of the revenues that we were normally expecting from this line and that prevented us from delivering the full value of the contract,” said  Serge Abergel, chief operating officer of Hydro-Québec US. “Our strategy for June, because we're not getting the full revenues, has been to really focus on these high-demand hours where we have a significant impact on prices because we lower prices for consumers, but we also get good revenues for us.”

Essentially, for now, Hydro-Québec is only flipping the switch when the rates are good.

The contract with Hydro-Québec only guarantees power during the summer months, May through October, with flexibility to provide electricity during other times of the year. New York already had two days of at least 90-degree temperatures at the end of last week, and the National Weather Service forecasts that this summer will be hotter than normal.

Energy consumer advocacy group New York Energy Consumers Council said New York City needs the power now.

“Champlain Hudson Power Express is critical for advancing New York City’s transition to renewable energy and ensuring that the City’s electricity supply remains dependable,” said Joe Baran, executive director of New York Energy Consumers Council. “If Champlain Hudson Power Express cannot consistently deliver affordable, sustainable, and reliable power, it raises significant concerns for the City’s energy future. We hope that these early challenges are simply temporary hurdles.”

The Governor’s office did not comment, but referred questions to Hydro-Québec.

Under a 25-year contract, the Champlain Hudson Power Express adds the equivalent power of a large-scale nuclear reactor and is one of the state's largest additions of renewable energy.

The infrastructure’s operational life is estimated to last up to 80 years, according to the New York State Energy Research and Development Authority, which is tasked with promoting statewide energy efficiency, renewable energy and emission reduction.

According to the New York Energy Consumers Council, the transmission lines are more reliable than wind and solar energy and can supply up to 20% of the city’s base load when it is at full output.

The power source delivers enough power for about 1 million households through a network of 61 hydroelectric power plants located in Quebec.

The project reduces carbon emissions by nearly 4 million metric tons statewide annually, equal to removing 44% of the passenger cars from New York City's streets, according to an analysis by a consultant hired by the project’s developers.