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/daily ·02 SEPT 2026 ·WEDNESDAY ·2 MIN READ ·7 STORIES

Wednesday 2 September 2026

Solar efficiency records fall in two labs on the same day, South Australia's rooftop fleet briefly runs the grid solo, and SK On's US gigafactory commits to domestic LFP supply — the kind of Wednesday that makes the policy noise easier to tune out.

01 / The Day

WEDNESDAY 02 SEPT 2026, ranked

07

Korean lab sets 26.7% world record for perovskite-CIGS tandem

Researchers at the Korea Institute of Energy Research pushed a sub-1 cm² perovskite-CIGS tandem to 26.7% efficiency through optimized inter-layer integration — a new record for a two-absorber architecture that sidesteps silicon's supply-chain dependency.

  • 26.7% verified efficiency on sub-1 cm² perovskite-CIGS tandem, a new world record
  • Achievement required optimized charge-transport layers and improved interface engineering
  • CIGS bottom cell avoids silicon supply constraints, unlike perovskite-silicon tandems
Why it mattersHigher tandem efficiencies on cheaper absorber pairs compress the $/Wp calculus for next-generation solar panels.
01 pv-magazine.com↗

World's largest solar-storage microgrid goes live in Saudi Arabia

The Red Sea Project's isolated grid — 358 MW of solar and 1.2 GWh of battery storage — reached full commercial operation, powering a luxury tourism destination with zero diesel and no transmission connection.

  • 358 MW PV plus 1.2 GWh BESS running as a fully isolated off-grid system at the Red Sea Project
  • Full commercial operation declared; system delivers round-the-clock clean power with no grid tie
  • Daily charge-discharge cycles under extreme desert heat provide real-world durability data at scale
Why it mattersA proven GWh-scale off-grid solar-storage system operating in extreme heat validates both technology durability and operating economics for replication globally.
02 pv-magazine.com↗

SK On locks 18 GWh LFP deal to supply US-made cells to NeoVolta

SK On will supply 18 GWh of lithium iron phosphate cells manufactured at its US gigafactory to storage integrator NeoVolta Power under a five-year agreement — one of the larger domestic LFP supply commitments since the Trump import ban reshuffled US storage sourcing.

  • 18 GWh over five years, LFP chemistry, cells produced at SK On's US manufacturing facilities
  • NeoVolta Power integrates utility-scale BESS projects for the US market
  • Signals SK On redirecting US gigafactory output from EVs toward stationary storage amid softer EV demand
Why it mattersDomestic LFP supply chains are being assembled in real time; 18 GWh is large enough to meaningfully shape near-term US storage project economics.
03 energy-storage.news↗

South Australia's rooftop solar briefly covers 99.9% of state demand

Residential PV systems in South Australia met essentially all of the state's electricity needs during peak midday generation on September 2 — a figure that would have been implausible a decade ago and that the grid absorbed using interstate exports and active controls.

  • Rooftop PV hit 99.9% of instantaneous state electricity demand at midday on September 2
  • South Australia holds the world's highest per-capita rooftop solar penetration rate
  • Balancing required active export controls, battery dispatch, and interstate interconnector flows
Why it mattersSouth Australia runs the world's most solar-saturated grid; its operating data sets the planning baseline for every other system chasing high-renewables targets.
04 pv-magazine.com↗

China restores Li-ion battery tax, exempts next-gen chemistries

Beijing reinstated a 2% consumption tax on lithium-ion batteries after an 11-year industry-seeding holiday; sodium-ion, solid-state, and other non-Li-ion chemistries are explicitly excluded — a textbook industrial-policy nudge toward the next generation.

  • 2% consumption tax on Li-ion batteries effective September 1, covering LFP and NMC cells
  • Sodium-ion, solid-state, and other emerging chemistries stay exempt from the new tax
  • Aligns with China's stated goal of accelerating post-lithium-ion commercialization
Why it mattersWhen the world's dominant battery market taxes its incumbent chemistry and exempts successors, capital and R&D spending reliably follow.
05 pv-magazine.com↗

Stabilizer-free perovskite cell hits 23.51% via seed crystals

Saudi researchers at KAUST achieved 23.51% efficiency on a perovskite solar cell using a seed-crystal nucleation approach that eliminates organic stabilizer additives — a major source of long-term degradation and manufacturing complexity.

  • 23.51% power conversion efficiency on a stabilizer-free perovskite absorber, verified
  • Seed crystals control grain nucleation, reducing defect density and improving stability
  • No organic stabilizer simplifies the coating process and removes a manufacturing cost layer
Why it mattersStability under real-world conditions is the commercial gating factor for perovskite solar; eliminating stabilizers while maintaining efficiency is a substantive step toward bankable module lifetimes.
06 pv-magazine.com↗

Netherlands 800 MWh Sirius BESS closes with Vattenfall toll

Return Energy's 200 MW / 800 MWh Sirius project in the Netherlands reached financial close alongside a long-term tolling agreement with Vattenfall — one of the larger standalone storage financings in Western Europe so far this year.

  • 200 MW / 800 MWh Sirius BESS in the Netherlands reached financial close on September 1
  • Long-term Vattenfall toll provides revenue certainty, de-risking the merchant storage model
  • Netherlands is one of Europe's fastest-growing BESS markets as offshore wind capacity ramps
Why it mattersFinancial close on a sub-GWh European BESS under a long-term toll shows the project-finance model for merchant storage reaching standard practice.
07 energy-storage.news↗
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