Key developments
Trump administration eases HFC phaseout rules
On May 21, the Trump administration moved to loosen federal rules for hydrofluorocarbons, with EPA Administrator Lee Zeldin expected to announce delayed compliance deadlines for grocery stores, air-conditioning firms, semiconductor plants, and refrigerated transport. The White House says the rollback would save businesses and households more than $2.4 billion, but critics note that HFCs are potent warming gases and that the United States has already committed with more than 190 countries to sharply reduce them.
Why it matters
It slows a major super-pollutant phaseout and weakens a key near-term climate mitigation policy.
Sources & driving stories
THE NEW YORK TIMES · Lisa Friedman
The New York Times coveragePBS NEWS
PBS News coverageNew South Wales launches major renewable tender
On May 21, New South Wales launched what officials called the biggest renewable-energy tender in the state's history, opening Tender 8 for 2.5 GW of renewable generation and Tender 9 for 12 GWh of long-duration storage. Tender 8 introduces a hybrid long-term energy service agreement that lets solar or wind projects pair with battery storage in a single project, with a minimum four-hour storage duration and selections expected by late 2026.
Why it matters
It is one of Australia's largest current procurement moves for clean power and storage, and it will shape near-term grid buildout.
Sources & driving stories
PV TECH · George Heynes
PV Tech coverageUN General Assembly backs climate ruling
On May 21, the UN General Assembly adopted a resolution backed by Vanuatu and other frontline countries affirming states' obligations under international law to protect the climate system, passing 141 to 8 with 28 abstentions. The vote follows the July 2025 International Court of Justice advisory opinion and gives the ruling added political weight even though it is nonbinding.
Why it matters
It strengthens the legal and diplomatic pressure on governments to align policy with climate obligations.
Sources & driving stories
TÜRKIYE
Türkiye coverageWorth noting
WORTH NOTING
California geothermal testbeds could cut costs
CATF says targeted state investment could de-risk exploration, unlock 5 to 10 GW of next-generation geothermal, and cut 2045 electricity supply costs by $10 billion to $44 billion a year.
WORTH NOTING
CSIRO climate-model cuts threaten ACCESS
Australia's science agency plans to cut 92 environment-unit jobs, including roughly a third of its climate modellers, raising concerns about the country's sovereign climate-model capability.
WORTH NOTING
Coal pollution reduced solar output 5.8%
A new study found coal-related aerosols cut global solar generation by 111 terawatt-hours in 2023, with the largest losses in China.
Still unclear
OPEN QUESTION
Will the HFC rollback face challenges?
The rule change could draw legal, industry, or state pushback and will determine how quickly the U.S. can keep cutting refrigerant emissions.
OPEN QUESTION
Will California fund geothermal testbeds?
The reported cost savings from next-generation geothermal depend on public investment that can de-risk exploration and attract private capital.