The week’s stories all point to the same underlying truth: the power sector is moving out of the era of symbolic targets and into the era of physical constraints. Regulators are dumping old clean-energy mandates, planners are looking for big steel fixes between regions, and China is treating firm power as a national priority rather than a thought exercise.

Arizona regulators voted unanimously to repeal the state’s renewable energy standard and tariff rules, arguing the mandates no longer make economic sense in a power market that looks nothing like it did in 2006.

The Arizona Corporation Commission said utilities including Arizona Public Service, Tucson Electric Power, and UniSource Energy Services have collected more than $2.3 billion in REST surcharges from customers to comply with the rules. The commission also argued that the policy forced utilities into above-market solar contracts, with those costs still flowing into customer bills through purchased power adjustments.

Opponents warned the repeal could create uncertainty for future clean-energy investment and weaken Arizona’s competitive position with tech and manufacturing firms looking for stable long-term clean power policy. But supporters of the repeal said utilities will still pursue the cheapest and most reliable generation under all-source procurement rules, without regulators prescribing the answer ahead of time.

Why it matters - For the grid: this is a sign that some states are moving away from first-generation renewable mandates and toward procurement frameworks built around cost and reliability.

For markets: the politics of renewables are changing from “how do we force more of it?” to “who is still paying for yesterday’s contracts?”

GridTake - The irony is that renewable mandates are being repealed not because renewables failed, but because they matured. Once a resource becomes mainstream, the subsidies, quotas, and procurement distortions used to force it into the system start looking less like policy and more like residue.

MISO and SPP are considering two major sets of 500-kV interregional transmission projects aimed at strengthening the grid along their southern seam in Arkansas, Louisiana, Oklahoma, and Texas.

The two portfolios under review are a Core package costing about $1.3 billion and a Core+ package costing about $3.6 billion. The larger Core+ set would increase MISO’s average import capability by 3.4 GW and SPP’s by 1.1 GW, while also delivering greater congestion relief and resolving more reliability issues across both systems. The smaller Core package would raise MISO import capability by 2.6 GW and SPP’s by 1.5 GW and is being pitched as more modular and expandable over time.

The projects come out of the two RTOs’ coordinated system planning process, which has historically produced plenty of studies and almost no steel. MISO and SPP are now taking comments and could push for approvals late this year or in early 2027, potentially along with FERC filings to improve interregional cost allocation.

Why it matters - For the grid: these projects go straight at one of the system’s weakest points, the lack of transfer capability between neighboring markets.

For policy: every serious interregional transmission proposal eventually runs into the same wall, which is not engineering but cost allocation.

GridTake - America loves the idea of interregional transmission in theory because every model says it saves money. In practice, it requires utilities and regulators to agree that someone else’s wires are also their problem. That’s where the romance usually dies.

China set a goal of reaching 110 GW of nuclear capacity by 2030, a roughly 76% increase from the end of last year, even after missing earlier five-year nuclear targets.

The new target reflects Beijing’s growing preference for nuclear as a source of around-the-clock, carbon-free electricity that can support continued load growth without the intermittency headaches created by large renewable buildouts. China is already on track to overtake France and the U.S. as the world’s largest producer of nuclear power by the end of the decade, with dozens of reactors under development and a construction model that has generally remained faster and cheaper than what the West has managed.

Analysts still question whether the 2030 deadline is realistic. Reactor construction in China typically takes five to seven years, which means the target may require counting plants still under construction rather than only operating capacity. But even if the exact number slips, the strategic direction is unmistakable.

Why it matters - For the grid: China is treating firm, dispatchable, low-carbon power as essential infrastructure, not as a boutique climate accessory.

For the West: every new Chinese nuclear target throws more light on how little actual building is happening in countries that talk constantly about clean firm power.

GridTake - China’s real advantage is not just that it likes nuclear. It’s that it still remembers how to think in terms of systems, timelines, and buildout. The West keeps debating the ideal future resource mix while China keeps pouring concrete.

PJM became the first U.S. grid operator to fully implement ambient-air adjusted transmission ratings under FERC Order 881, switching over on March 4 to hourly line ratings based on weather conditions.

Instead of relying on static thermal limits, PJM now adjusts line ratings in real time and up to 10 days ahead using ambient temperature forecasts across 47 weather regions in its footprint. The logic is simple: power lines can often carry materially more electricity in cold or windy conditions than on hot, still days. DOE researchers have found that favorable weather can raise usable line capacity by 10% to 40%.

The change required a multiyear overhaul of PJM’s operating, markets, and IT systems. PJM has long used seasonal and temperature-adjusted approaches, but this move makes it the first RTO to comply fully with the more granular framework required by FERC.

Why it matters - For the grid: this is one of the few changes that can unlock more transmission capacity without waiting a decade for new lines.

For markets: better ratings can reduce congestion costs and move more power across existing infrastructure, which matters a lot in a grid increasingly constrained by transfer bottlenecks.

GridTake - Dynamic line ratings are one of those embarrassingly obvious improvements that only look revolutionary because the industry waited so long to adopt them. If your grid is dispatching power based on the weather, it should probably also rate its wires that way.

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