Mammoth Solar hits 900 MW of commercial operation in Indiana
KEY DEVELOPMENTS
- Doral Commercializes 900 MW at Mammoth Solar: Three phases of the 1.3 GW utility-scale solar park in Indiana have reached commercial operation, cementing one of the country's largest solar installations. PV Tech. Read More: PV Tech.
- Wood Mackenzie: Batteries Beat Gas Peakers Globally: Four-hour battery storage costs have dropped below open-cycle gas turbines across modeled markets worldwide, though North America faces headwinds from tariffs, surging data center load, and shifting policy. PV Magazine. Read More: PV Magazine.
- Green Banks Scale Back Under Federal Freeze: Community solar in New Orleans, all-electric affordable housing in Salt Lake City, and low-income solar lending in Maryland are all proceeding at reduced scope as green banks navigate frozen federal funding. Canary Media. Read More: Canary Media.
- Energy Dome Plans 20 MW CO₂ Battery in Wisconsin: The Italian long-duration storage company opened a manufacturing plant and confirmed a 20 MW/200 MWh CO₂ battery system with Alliant Energy in Wisconsin, with plans to triple factory capacity by 2028 using €6.5 million in investment. PV Magazine. Read More: PV Magazine.
- PG&E Offers Cash-for-Electrification Over Gas Lines: California households whose gas pipes need replacing can now choose between a new gas line or funding to go all-electric, a novel approach to managing the building decarbonization transition. Canary Media. Read More: Canary Media.
Solar & Storage
Mammoth Solar keeps getting bigger. Doral Renewables reported that 900 MW across three phases of its sprawling Pulaski County complex have now reached commercial operation, according to PV Tech. The full buildout targets 1.3 GW, and the project's sheer scale — spread across thousands of acres of Indiana farmland — has made it a bellwether for how the Midwest absorbs utility-scale solar. For developers watching interconnection timelines and land-use fights elsewhere, Mammoth's operational progress offers evidence that very large solar plants can still get built in the current environment. Read More: PV Tech.
The cost story behind projects like Mammoth is shifting, though. A new Wood Mackenzie analysis finds that four-hour battery storage is now cheaper than open-cycle gas turbines on a levelized basis across global markets, with solar trackers remaining the lowest-cost new generation source in most regions modeled, PV Magazine reports. But North America is the outlier: tariffs, exploding data center electricity demand, and policy uncertainty under the Trump administration are creating cost pressures that blunt the advantage batteries enjoy elsewhere. For U.S. developers pairing solar with storage, the global cost curve is friendly — the domestic policy curve less so. Read More: PV Magazine reports.
Wood Mackenzie's broader storage outlook is bullish regardless. The firm forecasts the global energy storage market will grow to more than 7 TWh by 2035, with demand rising nearly 30% this year alone, according to a separate PV Magazine report. One sobering detail for U.S. players: Europe's annual storage installations now exceed America's. Contracted utility-scale storage capacity has topped 130 GW globally, meaning the pipeline is enormous — but execution, especially in a tariff-heavy U.S. market, is where the real test lies. Read More: separate PV Magazine report.
In long-duration storage, Energy Dome is betting on a different chemistry entirely. The company opened a CO₂ battery manufacturing plant in Italy and confirmed plans for a 20 MW/200 MWh system in Wisconsin with Alliant Energy, alongside projects in India and Ireland, PV Magazine reported. Energy Dome plans to triple its production capacity by 2028, backed by €6.5 million in investment. The Wisconsin project will be one of the first utility-scale CO₂ battery deployments in the U.S. — a technology that, if it performs, could offer multi-hour duration without the lithium supply chain constraints dogging conventional batteries. Read More: PV Magazine reported.
Meanwhile, solar tracker vendors face a maturing domestic market. With tracker penetration above 90% in U.S. utility-scale projects, North American shipments are forecast to decline from 2026 through 2035, per PV Magazine. Tracker companies are pivoting into adjacent hardware — particularly battery storage system components — to find growth beyond the roughly 10% of project capital expenditure that mounting systems typically represent. For investors in the tracker supply chain, the saturation signal is clear. Read More: PV Magazine.
Policy & Markets
Green banks are still deploying capital, but the guardrails are tighter. A Canary Media investigation found that federally backed green banks have scaled back their project pipelines amid the Trump administration's funding freeze. A community solar project in New Orleans, an all-electric affordable housing development in Salt Lake City, and low-income solar loan programs in Maryland are all moving forward — just smaller than originally planned. The freeze hasn't killed deployment, but it has forced green banks to ration, prioritizing projects that can close with reduced federal backstops. For community solar developers who rely on concessional capital to serve low-income customers, the math just got harder. Read More: Canary Media investigation.
In California, Pacific Gas and Electric is now giving households whose aging gas lines need replacement an unusual choice: accept a new gas pipe, or take funding to electrify instead, Canary Media reports. It's a practical solution to a growing problem — utilities are spending billions to maintain gas distribution networks with shrinking customer bases, and every new gas line locks in decades of fossil fuel use. The opt-out model could spread to other states wrestling with the same infrastructure question. For heat pump and electrical panel manufacturers, California just opened another channel. Read More: Canary Media reports.
On Capitol Hill, Rep. Jared Huffman is pushing for changes to the Senate's permitting reform legislation, according to Heatmap. Details of the specific amendments remain sparse, but any permitting overhaul has enormous stakes for renewable energy developers who routinely cite federal review timelines as a top constraint on project delivery. The tension between faster permitting for all energy projects — including fossil fuels — and environmental review protections has stalled multiple legislative attempts over the past two years. Read More: Heatmap.
LOOKING AHEAD
- Mammoth Solar Final Phase: Doral Renewables still has roughly 400 MW to bring online at its Indiana complex to reach the full 1.3 GW target; watch for construction updates and any interconnection queue developments that affect timing.
- Green Bank Adaptation: With federal funding frozen, green banks may increasingly turn to state and private capital sources — keep an eye on whether any states step in with substitute funding mechanisms before year-end.
- Senate Permitting Bill Markup: Rep. Huffman's push for changes signals the permitting reform debate is active heading into the midterm elections; any legislative text that emerges will reshape timelines for both renewable and fossil fuel infrastructure.
TODAY'S QUICK ANSWERS
Q: What do tariffs mean for the U.S. battery storage cost advantage over gas peakers?
A: Globally, four-hour batteries now beat open-cycle gas turbines on cost, according to Wood Mackenzie. But North America is the one region where that advantage is being eroded by trade headwinds. Tariffs on imported battery cells and components, combined with surging data center electricity demand, mean U.S. developers may not fully capture the cost decline that storage enjoys in Europe and Asia-Pacific. Projects that can source domestic cells or qualify for remaining production tax credits will have a meaningful edge over those that cannot.
Q: Why should developers watch California's gas-line-or-electrify model?
A: Because it creates a replicable template. Every U.S. gas utility faces the same aging-infrastructure dilemma — replace pipes serving a potentially shrinking customer base, or redirect that capital toward electrification. If PG&E's opt-out program gains traction, regulators in other states may adopt similar frameworks, creating a steady stream of residential electrification projects funded by utility ratepayer dollars rather than federal incentives.
Q: What does Europe's storage lead mean for U.S. competitiveness?
A: Wood Mackenzie now shows European annual storage installations exceeding U.S. volumes — a reversal that reflects both EU policy momentum and American headwinds from tariffs and federal policy uncertainty. With the global contracted pipeline above 130 GW, U.S. developers risk losing supply chain priority to faster-moving markets if domestic deployment doesn't accelerate.
THE BOTTOM LINE: Batteries are cheaper than gas peakers nearly everywhere on Earth now — but tariffs and policy churn mean U.S. developers are fighting harder than their global peers to capture that advantage, even as landmark projects like Mammoth Solar prove that large-scale clean energy can still get built in America.