US RENEWABLES TRACKER: CAISO only region to see renewable output up in Q2

The surge of hydroelectric generation this year pushed up the California Independent System Operator's total renewable generation output in second quarter 2023, the only region where total renewable output increased year on year.

CAISO hydro output jumped 89% from a year ago to average 85 GWh/day in Q2, helping its total renewable output to increase 12.5% to an average of 326,433 GWh/day, according to grid operator data. CAISO's total share of renewable generation jumped 20 percentage points from Q1 and rose 7.5 points year on year to account for 56.3% of its total fuel mix in Q2, the biggest increases across the US.

Renewable additions

California added the most renewable capacity in Q2 with 867 MW of solar and battery storage coming online, accounting for 15% of all Q2 installations, according to the American Clean Power Association's Q2 report. Texas added 727 MW of renewable capacity added in Q2, while Michigan added 537 MW and was the only state in the top three to add wind capacity in Q2.

Overall, the US added 5.2 GW of wind, solar and battery storage capacity in Q2 2023, the second highest Q2 to date, according to ACP. The US has a total of 237.345 GW of operating clean power capacity. Land-based wind leads with 146.433 GW, followed by solar with 79.8 GW, storage with 11.071 GW and offshore wind with 42 MW.

"The influence of the Inflation Reduction Act is evident in the project development pipeline," ACP said in its Q2 report. "The 145,592 MW in the pipeline represents a 13% increase from Q2 2022, and a 43% increase from Q1 2021."

There are currently 145.592 GW in the renewables pipeline and Texas leads with 26.353 GW, followed by California with 15.918 MW and New York with 9.217 GW.

ERCOT is expected to catch up with CAISO on solar and storage on a MW basis, said Sam Huntington, a director on the North American power research team with S&P Global Commodity Insights.

"Their interconnection process is just so much quicker and the market fundamentals are still great, especially with growing demand," Huntington said. "My one caveat to that is that they may take a little longer to surpass CAISO in terms of storage MWh since CAISO installs mostly four-hour storage, while ERCOT installs mostly 1 or 2-hour storage. So ERCOT needs twice the storage MW to get the same MWh."

Solar soars

Solar had the most additions in Q2 with 2.74 GW added, followed by battery storage with 1.51 GW of capacity added and land-based wind capacity with 968 MW, according to ACP.

"Solar is on an absolute tear thanks to pent up demand and prices falling again," Huntington said. "There's a decent chance we'll see over 20 GW of utility-scale solar installed this year, plus another 6 GW behind the meter."

California leads the US in solar capacity with 17.934 GW by the end of Q2, followed by Texas with 13.067 GW, according to the ACP. Seventeen states had over 1 GW of capacity, while 31 states had less than 1 GW. North Dakota and West Virginia were the only states with no wind capacity.

CAISO manages the flow of electricity for about 80% of California and a small part of Nevada. CAISO set a solar generation peak record of 16.044 GW Sept. 6.

CAISO had the most solar market share in Q2 accounting for 23.5% of its total fuel mix, according to grid operator data. CAISO solar generation output was up 6% year on year to average 136.5 GWh/d, the most across the US.

However, the Electric Reliability Council of Texas had the biggest year-over-year jump in solar output at 32% to average 101.3 GWh/d in Q2, according to ERCOT data. ERCOT manages the flow of electric power for about 90% of the state's electric load.

ERCOT expects to reach 19.64 GW of installed solar capacity by the end of the year, 35.9 GW in 2024 and surpass 50 GW in 2025, according to its monthly Capacity Changes by Fuel Type report.

In CAISO, there's 5.318 GW of solar in its interconnection queue that have executed interconnection agreements and are slated to come online this year, followed by 5.28 GW in 2024 and 1.367 GW in 2025. About 90% of those projects have battery storage attached, totaling over 10 GW of storage.

Wind generation

Texas led the US in wind capacity with 40.6 GW by the end of Q2, followed by Iowa with 13 GW and Oklahoma with 12.5 GW, according to ACP. Twenty-three states had over 1 GW of capacity, while 18 states had less than 1 GW. Nine states have no wind capacity.

Half of the top 10 states for wind capacity are in the Southwest Power Pool's footprint, according to ACP data. SPP oversees the electric grid and wholesale power market for companies in 15 states in the central US.

SPP has 1.6 GW of wind capacity on scheduled to come online this year with interconnection agreements executed, followed by 2.7 GW in 2024 and 5.2 GW in 2025, according to its generation interconnection request report.

Although SPP had the most market share of wind in Q2 with 36.9% of its total fuel mix, wind generation output was down year on year across the entire US. ERCOT had the biggest drop in wind output, plunging 24% year on year to average 283.9 GWh/d in Q2, according to grid operator data.

ERCOT expects to reach 38.3 GW of installed wind capacity by the end of the year, nearly 40.5 GW in 2024 and surpass 42 GW in 2025, according to its monthly Capacity Changes by Fuel Type report.

CAISO has less than 600 MW of wind in its interconnection queue that have executed interconnection agreements and are slated to come online in 2023-2025, followed by 5.28 GW in 2024 and 1.367 GW in 2025. About 40% of those projects have battery storage attached.

Battery storage capacity

California had the most battery storage capacity at 5.786 GW by the end of Q2, an increase of 15% from Q1. Texas followed with 2.373 GW, up 9.6% quarter on quarter, according to ACP. Eleven states had over 100 MW of capacity, while 31 states had less than 100 MW. Eight states have no battery storage capacity.

The Western US had 95% of the nation's battery storage capacity additions in Q2, according to an S&P Global Commodity Insights compilation of various government filings.

ERCOT expects to reach 5.6 GW of installed battery capacity by the end of the year, 17 GW in 2024 and over 17.5 GW in 2025, according to its monthly Capacity Changes by Fuel Type report.

CAISO has 75 projects in its interconnection queue that have executed interconnection agreements with battery storage as the main fuel source, including 4.3 GW slated to come online in 2023, 3 GW in 2024 and nearly 6.3 GW in 2025.