SACRAMENTO, Calif. (KTXL) — Power generators in Roseville and Yuba City helped California’s power grid make it through the Labor Day heat wave, the Department of Water Resources said. 

The power generators were brought online at the request of the California Independent System Operator. 

The four generators were deployed by the DWR in Roseville and Yuba City. They were able to supply the grid with enough energy to power 120,000 homes. 

On Sept. 1, 2021 the city of Roseville approved the installment of the two 30 megawatt natural gas generators with the understanding that Roseville would be paid $9 million over the course of the agreement, according to city reports.

The city reports also show that the agreements for the operation of the generators at the Roseville Energy Park ends on Dec. 31, 2023.

Contractors with DWR installed the generators and the city of Roseville will be reimbursed for all the costs associated with running and maintaining the generators by the state, according to city reports.

At the conclusion of the agreement the city has the option to purchase the generators, according to city reports. One at the cost of $10 million and the other at the cost of $11 million.

City reports show that the time estimated cost of the new generators at $20 million and could be used to replace aging generators the city was planning to phase out.

The two generators went online with the statewide grid in mid-September 2021.

According to the DWR, it’s the first time the generators were used since being installed in 2021. 

“DWR has been planning for this moment for months and we’re proud of our role in safeguarding the statewide energy grid,” Director Karla Nemeth said. 

The generators are powered by natural gas and are meant to be temporary. 

“The program is designed to support a transition to a clean energy future and is temporary in nature,” the DWR said in a news release. 

California’s power grid is expected to be strained again on Tuesday as the heat wave persists.