The clean energy industry experienced its slowest quarter in three years this summer, an industry group reported Wednesday.

The American Clean Power Association said the federal Inflation Reduction Act — passed in August — holds promise for future growth. But the industry was held back in the third quarter by supply chain constraints, trade and tariff issues, and uncertainty over tax policy.

Clean power projects totaling 14.2 GW capacity were delayed in the third quarter, and more than half of them had been delayed in the second quarter, as well. ACP said it is aware of 36.2 GW of delayed projects and 3.5 GW of terminated or canceled projects.

For the quarter, new utility-scale projects totaling 3.4 GW were installed, 22% less than in the third quarter of 2021.

Wind power installations were down 78% and solar down 23%. The exception was battery storage, which is having its best year on record.

JC Sandberg, interim CEO of ACP, said policy and regulatory issues continue to hamper growth.

“The solar market has faced repeated delays as companies struggle to obtain panels as a result of an opaque and slow-moving process at U.S. Customs and Border Protection,” Sandberg said in a news release. “Policy uncertainty around tax incentives constrained wind development, underscoring the near-term need for clear guidance from the Treasury Department so the industry can deliver on the promise of the IRA. Storage was the one bright spot for the industry and had its second-best quarter on record. The aggressive deployment of storage continues to drive down consumer energy costs and enhance grid reliability.”

Sandberg said the Inflation Reduction Act should be a major catalyst for the clean energy industry.

“ACP anticipates that the IRA will give industry the tools it needs to more than triple annual installations of wind, solar, and battery storage by the end of the decade. We expect the IRA to deliver 550 GW of new capacity by 2030, representing $600 billion in capital investment and growing the clean power workforce to nearly a million strong by 2030.”

Some highlights of the report:

• Between July and September, 4.6 GW of clean energy projects entered advanced development and 2.5 GW began construction. In total, 93 GW was in advanced development and 39 GW was under construction by the end of the quarter.
• Solar accounts for 63% of delays, wind 23% and battery storage 14%. Detained panel shipments are the biggest cause of delays for solar projects, and wind installations are most frequently hampered by supply chain disruptions and grid interconnection delays.
• Power purchase agreements for green energy totaled 7.2 GW for the third quarter, and the wind and solar market-averaged national price index reached a new high: $45.93 per MWh, 10% more than the previous quarter and 34% higher than a year earlier.
• Texas remains the leader in clean power, with 149.39 GW operational, 11.2 GW under construction, and 12.6 GW in advanced development, each metric the highest among the 50 states. Its third quarter installation total was 1.27 GW, second only to California’s 1.4 GW.