About 2.6 TW of planned power projects were seeking to connect to the U.S. grid at the end of last year, up 27% from the year before and representing twice as much as the country’s existing generating capacity, according to a report released Wednesday by Lawrence Berkeley National Laboratory.

Solar, battery and wind projects make up 95% of the capacity in the interconnection queues. More than 1 TW of solar and 1 TW of battery storage are in the queues, mostly in hybrid projects, followed by 360 GW of wind and 79 GW of gas-fired generation, LBNL researchers said in their annual “Queued Up” report.

A map of the United States showing pending generator interconnection queues.

Capacity in U.S. interconnection queues at the end of 2023.

Retrieved from Lawrence Berkeley Livermore **change Livermore to National** Laboratory.

The annual number of interconnection requests and their capacity has surged since 2013, according to the report. Last year, projects totaling 908 GW joined interconnection queues, up from a 759 GW increase in 2022 and a 561 GW increase in 2021.

More than 1.2 TW has joined interconnection queues since the passage of the Inflation Reduction Act in 2022, including about 540 GW of storage, 500 GW of solar and 125 GW of wind, according to the report.

The LBNL researchers found that projects in interconnection queues totaling 311 GW, or 12% of the queue capacity, have executed interconnection agreements, typically the last part of the interconnection process.

Only 14% of the capacity in interconnection queues from 2000 to 2018 has been built, according to the report. In that period, completion rates for gas projects totaled 31%, followed by wind at 20%, solar at 13% and batteries at 11%.

The West, outside California, has the largest queue at 706 GW, followed by the California Independent System Operator with 523 GW, the researchers found.

The average time projects spend in queues before being built has increased. The typical project built in 2023 took almost five years between requesting an interconnection study to beginning commercial operations, compared to three years in 2015 and less than two years in 2008, the researchers said.

Variable solar and wind resources contribute a smaller percentage of their nameplate capacity to resource adequacy and peak load compared to dispatchable generation like natural gas, the researchers noted.

“Decarbonizing the electric sector requires higher levels of installed solar and wind capacity to achieve the same resource adequacy contributions,” the researchers said. “High levels of storage can offset this need to some degree.”