Last Friday, we did an episode about the 24 states considering legalizing plug-in solar.

It’s already our most listened-to episode by far since starting This Week In Solar, so we thought we’d take a deeper dive this week.

What Is Plug-In Solar?

For decades, going solar has been a big project, requiring:

* Home ownership

* Thousands of dollars in permits

* Permanent roof modifications (in most cases)

But in the last few years, we’ve started to see mass market “plug-and-play” solar kits all around the world.

These are often called “balcony solar” systems because anyone can slap them on a balcony, plug them into a standard wall outlet, and reduce their electric bills.

In many European countries, you can buy these kits in retail stores, go home, hang them on a railing, and start saving money immediately.

I was in Europe last fall with my family, and I can verify that these kits are absolutely everywhere. (Fun fact, the German word for them is Balkonkraftwerke).

The History of Balcony Solar

This idea isn’t new.

As far back as 2011, when the U.S. Department of Energy launched the SunShot initiative, it included a $25 million grant specifically for “Plug and Play” solar innovation.

However, for the last 15 years, American plug-in solar adoption has been stalled by utility rules only designed for one-way power flow and the permitting nightmares that plague the solar industry.

While the U.S. stagnated, Germany became the global testing ground for balcony solar.

Following a 2019 move to streamline utility connection rules, adoption there exploded. By 2023, Germany saw a quadrupling of legal interconnected systems, proving that if you remove red tape, the public will choose to own their own power.

As of mid-2025, Germany had nearly 800,000 registered balcony solar installations.

Why Europe is So Far Ahead

* High Electricity Rates: Energy prices in Europe have historically been much higher than in the U.S., meaning that a $600 kit pays for itself in less than three years.

* Rental Culture: Over half of Germans rent their homes. The “Solar Package I” policy of 2024 legally protected tenants’ rights to install these systems. It put the burden of proof to deny them on the landlords, who must now provide documentation if they want to refuse a balcony solar system to a tenant.

* Standardization: Europe adopted a standard 800W inverter capacity limit for these systems, which allowed these kits to be treated as household appliances rather than power plants.

UL 3700 Saves The Day?

We’re finally seeing enough demand for balcony solar that a major breakthrough in the U.S. market happened on January 7, 2026.

UL Solutions, a company that provides independent testing, inspection, and certification of all kinds of products, released certification documentation that addresses the major safety hurdles.

This includes things like:

* Touch Safety: The system must shut off power to the plug’s metal prongs in less than one second if it’s unplugged, preventing shock risks.

* Breaker Masking: Systems must monitor the total current in a circuit to ensure that the combined power from the grid and the panels never exceeds the safe limits of your home’s wiring.

Now that plug-in solar kits can be built to an agreed-upon set of standards, utility companies don’t have as strong a case, and there’s less for legislators to push back on.

So, Which States Are Thinking of Legalizing?

Currently, more than 24 states are advancing bills to legalize these systems. Here is where the major players stand:

* Utah (The Pioneer): Passed HB 340 in 2025, allowing plug-in systems up to 1.2 kW without utility approval or fees.

* Virginia: HB 395 is currently moving through the Senate. Similar to Germany’s solution, it would prevent localities and landlords from prohibiting portable solar for apartment dwellers.

* California: The “Plug Into the Sun Act” (SB 868) is currently before the Senate Energy Committee. It aims to reclassify these kits as appliances like toaster ovens to bypass expensive permits.

* New York: The SUNNY Act (SB 8512) seeks to remove regulatory barriers specifically to provide “equitable access” for renters in high-density urban areas.

* Maine & New England: Bills are currently moving through committees in Maine, Rhode Island, and New Hampshire to help residents combat some of the highest utility rate hikes in the country.

What’s Standing in the Way?

The final hurdle is utility resistance.

Monopoly utilities in states like Wyoming and Arizona have successfully lobbied to kill plug-in bills, arguing that they cannot be assured of the quality of consumer-installed products.

On February 20th, Wyoming actually voted its bill down.

Their protests are mostly based on “islanding,” saying that a system might stay energized during an outage or grid repair, posing a risk to line workers.

However, as we now know, UL 3700-certified kits are engineered to shut down instantly during outages.

While we wait for the states and federal government to legalize these kits, there are several companies taking matters into their own hands, like Raya Power.

Raya’s built a combined solar and battery kit that anyone, including renters, can buy and install themselves. It:

* Bypasses the electric panel and backs up critical appliances directly, eliminating any worries about backfeeding the grid

* Lowers bills by running those critical appliances with solar and battery power

* Backs those appliances up in emergencies

Hopefully, as this technology becomes too good to say no to, we’ll see more solutions like Raya’s.

Sources:

Power surge: law changes could soon bring balcony solar to millions across the US

UL Solutions Debuts Testing and Certification Framework for Safer Plug-In Solar Across the United States

How to build a balcony solar kit to UL certification

Lawmaker announces bipartisan plan to allow plug-and-play solar panels in new US markets: ‘People can … just go to Costco or Ikea’

The Plug-In Solar Revolution Comes To America

Lawmakers pull the cord on plug-in solar bill

The SunShot Initiative

Lawmakers pull the cord on plug-in solar bill

Raya Power

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