On Sun Day, September 21, We Shined A Light on Clean Energy

Over the weekend of September 20, 2025—to coincide with the Autumnal Equinox—communities across the country joined together for Sun Day, a national day of action demanding the rapid deployment of clean energy.

 

On Sunday, September 21, the Autumnal Equinox, when the sun shines equally around the world, we celebrated Sun Day—a day to rise up for clean energy. Why? Because we need to speed up and scale up solar and wind and renewable energy at a much faster pace. It is one of the most critical steps we can take to avoid the worst impacts of climate change and power the future with clean, affordable, and reliable electricity.

The U.S. has all the clean energy we need. Solar and wind are now the cheapest, most efficient sources of electricity in history. Yet fossil fuel billionaires and their allies are working overtime to stall progress by blocking rooftop and utility-scale solar, attacking EV and renewable energy credits, and slowing clean infrastructure.

 

• In 2024, the U.S. added more solar power to the grid than any other source has in 20 years: 50 gigawatts, enough to power 8.5 million homes.
• Solar and storage made up 84% of all new electricity capacity added last year.
• According to the UN, solar power is now 41% cheaper than fossil fuels worldwide.
• Even states like Texas and Indiana are leading—not for ideology, but because clean energy beats fossil fuels on cost, speed, reliability, and jobs.
• Yet, rooftop solar costs three to four times more in the US than in Europe and Australia due, in part, to outdated and costly permitting rules.

 

For decades we’ve called this stuff ‘alternative energy.’ That’s not true anymore—this is the common-sense, obvious way to power our future.

—Bill McKibben, Climate activist, writer, and co-founder of Third Act

 

 

With more than 500 events in 49 states, Sun Day showed there is overwhelming public support for clean energy in every corner of the country, and sent lawmakers a clear message: stop siding with polluters, and start making it easier—not harder—to plug-in to clean energy. That means cutting red tape that slows rooftop solar, making clean energy affordable for renters and low-income families, investing in batteries and modernized grids, and holding fossil fuel companies accountable for decades of willful pollution and obstruction.

How We Celebrated Sun Day

Third Act Working Groups hosted about 160 Sun Day events ranging from solar array and battery tours, public art displays, educational displays at libraries, Sunbeam Congregations, solar and electric home tours, rallies and festivals, and more! Educational fairs included booths on small, plug-in “balcony solar,” installers of rooftop solar and heat pumps and induction stoves (drive on sunshine! cook on sunshine!), climate and clean energy organizations with advocacy actions people can take, kid-friendly information about how solar works, toy solar car races, art-making, music, and wonderful community building. Notable events included the launch of a national campaign to install 10,000 solar systems on affordable housing, the dedication of 17 new electric school buses in Northern Virginia, and Indigenous-led celebrations in Monument Valley featuring bands performing with solar-powered sound systems. Check out more blogs and resources from our amazing Working Groups to learn more about what folks did on Sun Day. 

 

 

 

Early Results

Our goals for the Sun Day national weekend of actions were to build a visible and vocal movement to support clean energy, to grow our partnerships with diverse organizations, to show that people all across the country support clean energy, to have people take action to speed up and scale up solar, and to help change the story that solar and renewables are no longer “alternative energy” but are the best, cleanest, most affordable, and reliable way to power our future.

So, what’s our impact so far? Here’s a round up:

• More than 500 events in 49 states, with tens of thousands participants
• More than 80 partners nationally, and even more locally. The Portland, Oregon event alone had 90 partners. We built a bigger tent – youth organizations, companies like Solar One and Crafstrom (balcony solar); solar energy industry association chapters, Green Workers Alliance, schools, faith organizations – churches, synagogues, United Church of Christ, Dayenu, Green Faith; GiveSolar and putting solar on affordable housing, climate groups, parent organizations like Mothers Out Front and Moms Clean Air Force, elected officials, and more!
• More than 65 media hits, and still growing, including the New York Times, CNN, The Guardian, and more, while social media reached more than 1 million.
• The Sun Day petition to mayors, calling on local leaders to simplify solar permitting, has more than 40,000 signatures. You can still sign (if you haven’t already), share with others, and help us get to 50,000!
• Six states, so far, have plans to introduce legislation to make legal small-scale, plug-in solar—also known as “balcony solar.” There is currently a legal gray area for this technology in the U.S. It is already legal and popular in Europe and Australia. Utah was the first state to pass balcony solar legislation in 2025. 
• The State of Wisconsin, the City of Philadelphia, and the town of Branford, Connecticut all passed proclamations recognizing Sun Day and acknowledging additional clean energy reforms that their state, city, and town can make. Advocates will use these proclamations to keep the pressure on state and local decision-makers to do more.
• Officials like Brad Lander, the NYC Comptroller who spoke at the Sun Day NYC event, committed to keep divesting public pensions from fossil fuels and invest in clean energy solutions.

What’s next?

 

Sun Day was just the beginning! We need to keep shining a light on the many solutions and actions at hand. Here are ways you can help keep the momentum going and stay plugged in to efforts to advance the clean energy revolution:

• Watch the recording of our quarterly (virtual!) September All-In Call—our special guest was clean energy pioneer Jigar Shah—who shared how we can drive real progress without waiting on Washington. Plus, folks got a preview of our Simplified Solar campaign, aimed at slashing the “soft costs” of solar—permitting, paperwork, and red tape—that make up two-thirds of total installation costs in the U.S.
• Sign our petition calling on local leaders to remove legislative barriers that prevent people and cities from implementing solar and other clean energy! Together with you and local activists, we will deliver the petition signatures to mayors across the country as part of our Simplify Solar campaign. 
• Join the Simplify Solar campaign launch on October 16 to cut costs and red tape and simplify permitting at the local and state level. Register for the call. 
• Invest in the Sun and Divest from Fossil Fuels: Watch the webinar about how you can invest in clean energy projects (for as little as $10) and read our interview with Clean Energy Credit Union about how you can get banking services without fossil fuels. 
• Watch “The Light Won’t Dim” 30-min documentary and discuss with friends using our discussion guide. 

 

Keep on shining!