California rewrites its grid playbook with a sweep of new energy laws
KEY DEVELOPMENTS
- California Enacts Sweeping Grid Modernization Laws: Governor Newsom signed SB 905, SB 913, and several other bills establishing plug-in solar rules, opening wholesale markets to virtual power plants, and enabling farmer-built solar on marginal land. SEIA praised the package for expanding access to clean energy. (PV Magazine USA) Read More: PV Magazine USA.
- Antora Plans 5.8-GWh Thermal Battery in Kansas: Antora Energy, flush with $550 million from a Series C round, will build a 5.8 GWh thermal battery energy storage system at a biorefinery in Pratt, Kansas — one of the largest non-lithium storage deployments announced in the U.S. (PV Magazine USA) Read More: PV Magazine USA.
- Michigan Regulators Approve DTE-Google Data Center Deal: The Michigan Public Service Commission greenlighted DTE Energy contracts to supply a 1-gigawatt Google data center in Van Buren Township, expected online by December 2027. (Michigan Advance) Read More: Michigan Advance.
- Residential Solar-Storage Pairing Hits 37% Nationally: Battery attachment rates on new U.S. rooftop solar systems jumped from 25% in 2024 to 37% in 2025, with California leading at 74% — a shift driven largely by the state's Net Billing Tariff. (PV Magazine) Read More: PV Magazine.
- Senate Permitting Bill Faces Skepticism Before Vote: A bipartisan Senate permitting bill introduced by Senator Sheldon Whitehouse and others draws scrutiny over whether it constitutes a genuine overhaul or falls short of a comprehensive deal, with a vote expected after the midterm elections. (Heatmap News) Read More: Heatmap News.
Solar & Storage
The week's project pipeline tells a consistent story: utility-scale solar keeps coming online even as the federal policy environment remains uncertain. ContourGlobal and Platte River Power Authority completed a 324-MW solar complex in Colorado, a project first flagged this week as the Black Hollow Sun project near Severance reached full operation. For municipal utilities like Platte River, which serves Fort Collins and several northern Colorado cities, the project locks in solar generation at a scale that materially shifts their resource mix. Read More: first flagged this week.
In Michigan, DTE Energy finished its 100-MW Cold Creek Solar Park near Coldwater, backed by a purchase commitment from Ford Motor Co. through DTE's CleanVision MIGreenPower program. Ford has committed to buying up to 650 MW of renewable energy from DTE and aims to power all Michigan vehicle manufacturing with 100% carbon-free electricity by 2027 — a target now less than 15 months away. That DTE also won regulatory approval the same week for contracts to supply Google's planned 1-gigawatt data center in Van Buren Township, due online December 2027, signals how aggressively the utility is positioning itself as a conduit between clean power generators and the corporate buyers driving new load growth. Read More: due online December 2027.
On a smaller but symbolically notable scale, Six Flags Magic Mountain in Los Angeles County completed a 12.37-MW solar carport project developed with Solar Optimum. It's now the largest solar carport installation in California and is designed to offset 100% of the theme park's energy consumption. Commercial carport solar remains a niche segment, but projects like this one demonstrate that high-visibility, space-constrained sites can pencil out at double-digit megawatt scale. Read More: the largest solar carport installation in California.
The storage side delivered one of the more unusual announcements of the season. Antora Energy will build a 5.8-GWh thermal battery at a biorefinery in Pratt, Kansas, pairing industrial heat decarbonization with long-duration storage at a scale few thermal battery companies have attempted. Antora raised $550 million in a Series C and has been expanding manufacturing capacity in San Jose, California. For developers and investors tracking alternatives to lithium-ion, this project will be a closely watched proof point — particularly in industrial applications where electrification of process heat has proved stubborn.
Meanwhile, the residential solar-plus-storage market is consolidating around batteries as standard equipment rather than a premium add-on. Nationwide, 37% of new rooftop solar systems installed in 2025 included battery storage, up from 25% the year before. California's 74% attachment rate — driven by the Net Billing Tariff that slashed export compensation — shows where the rest of the country is heading as more utilities shift to time-of-use and net billing structures. Texas saw particularly strong growth as well, though the data paints a market where economics, not environmentalism, is doing the persuading. Read More: 37% of new rooftop solar systems installed in 2025 included battery storage.
On the supply chain front, global polysilicon prices held steady at $19.312/kg as Chinese producers' attempts to push prices higher met buyer resistance. Contractual delivery obligations are becoming harder to fulfill, and U.S. Department of Commerce regulatory actions continue to inject uncertainty across modules, inverters, and battery storage procurement — a dynamic that downstream developers should factor into Q1 2027 equipment timelines. Read More: Contractual delivery obligations are becoming harder to fulfill.
Policy & Markets
California's legislative haul warrants a closer look. The bills Newsom signed go beyond incremental clean energy support. SB 905 and SB 913 target grid modernization through coordinated networks of customer-owned batteries, smart thermostats, and electric vehicles — essentially formalizing the virtual power plant as a grid resource and opening wholesale market participation. Separate measures establish plug-in solar rules and allow farmers to build solar on marginal land. For developers, the virtual power plant provisions matter most: they create a regulatory pathway for aggregated distributed resources to compete directly with gas peakers for grid services. SEIA praised the package for broadening access to clean energy benefits, and the legislation positions California as the first large state to codify VPP participation at this scale. Read More: SEIA praised the package.
In Washington, a bipartisan Senate permitting bill is drawing both attention and skepticism. Senator Sheldon Whitehouse introduced legislation that would significantly reform federal permitting for energy projects, and lawmakers from both parties have backed it. But analysts are questioning whether the bill constitutes a genuine overhaul or something more modest. Heatmap News reports skepticism about calling it a "grand bargain," and the vote is expected only after the November midterm elections — meaning its fate may depend on the composition of the next Congress. For clean energy developers stuck in multi-year interconnection and permitting queues, the bill's trajectory matters more than its label. Any acceleration of federal review timelines would directly affect project economics and financing schedules. Read More: significantly reform federal permitting, Heatmap News reports.
LOOKING AHEAD
- Senate Permitting Vote Timing: The bipartisan permitting bill is expected to come to a vote after November's midterm elections, making the election results a key variable for the legislation's prospects.
- Ford's Michigan Clean Energy Deadline: With Ford targeting 100% carbon-free electricity for all Michigan vehicle manufacturing by 2027, the automaker's remaining procurement gap — after Cold Creek Solar's 100 MW and up to 650 MW committed from DTE — will come into sharper focus in coming months.
- California VPP Market Rules: Implementation details for SB 905 and SB 913 will determine how quickly virtual power plant aggregators can enter California's wholesale energy markets and at what scale — a process to watch through 2027.
TODAY'S QUICK ANSWERS
Q: What does California's new VPP legislation mean for battery storage developers and aggregators?
A: The bills create a formal regulatory pathway for coordinated networks of customer-owned batteries, smart thermostats, and EVs to participate in wholesale energy markets. This matters because it moves virtual power plants from pilot programs to codified grid resources — potentially giving aggregators a revenue stream competitive with gas peakers. With California's residential battery attachment rate already at 74%, the installed base to aggregate is already substantial.
Q: Why should developers outside Michigan pay attention to the DTE-Google data center approval?
A: The 1-gigawatt Google facility approved this week is part of a nationwide wave of hyperscale data center load that is reshaping utility resource planning. Regulators approving contracts of this size signals growing comfort with single-customer loads that rival small cities in power consumption. Developers in any state with data center demand should watch how DTE sources that gigawatt — the procurement mix between solar, storage, and firm generation will set precedents.
Q: What does the 37% residential solar-storage attachment rate signal for equipment suppliers?
A: The jump from 25% to 37% in a single year — with California at 74% — indicates batteries are becoming a default rather than an upsell. Equipment suppliers and installers should plan for attachment rates above 50% nationally within the next two to three years, particularly as more states adopt net billing or time-of-use rate structures that penalize unmanaged solar exports.
THE BOTTOM LINE: California's new laws formalizing virtual power plants as wholesale market participants, combined with a 37% national battery attachment rate that's still climbing fast, signal that distributed storage is no longer a sideshow — it's becoming grid infrastructure, and developers and utilities that treat it otherwise risk being caught flat-footed.