Permissionless Batteries: A New Tool for Energy Equity—or Another Missed Opportunity?

A home battery storage system, without solar, can cost upwards of $12,000. With that price tag, the households that could most benefit from resilient power technologies, such as those with high energy burdens or electricity-dependent home medical needs, are the least able to access them.

Enter permissionless batteries.

Also known as plug-in batteries or plug-and-play batteries, these small, modular battery energy storage systems can plug into a standard electrical outlet, rather than being hardwired into a building’s electrical panel, and provide backup power to select loads. Importantly, “permissionless” doesn’t mean no rules. Rather, it describes a battery designed to operate within existing electrical limits and safety standards in a way that does not require permission from the utility to interconnect in the traditional sense.

Permissionless batteries are a trending topic and rightfully so: there’s real potential to disrupt the long-dominant residential gas generator market through affordable, renewable energy technologies. Permissionless batteries could be sold in the same aisle as gas generators. They can take up minimal space, be deployed without extensive electrical work, and provide backup power to household devices with a plug.

There’s also an opportunity to alleviate household energy burdens. The newest models can charge from the grid and/or a solar array (also increasingly available as a plug-in, permissionless resource) and discharge power through a standard wall outlet. While discharging a permissionless battery back to the grid is not currently permitted, if utilities and regulators can accommodate this discharging capability, households could potentially earn revenue or utility bill credits for providing valuable grid services.

A small pilot in New York City is exploring using permissionless batteries in a virtual power plant, a model in which distributed resources like batteries are aggregated to provide grid services, such as reducing energy demand during peak periods. The pilot, Responsible Grid, provides free permissionless batteries to 65 rental households, plus $100 for each air conditioner plugged into the battery. During times of high energy demand, when temperatures are high and air conditioning use soars, these air conditioners are powered by the batteries instead of the grid – lowering expensive peak energy demand and allowing the participants to continue optimizing their air conditioning while other New Yorkers are encouraged to conserve energy to reduce demand on the grid.

Because they cost significantly less than hardwired batteries and don’t require time-consuming permitting processes, permissionless batteries are a promising tool in narrowing the energy equity and resilience gap. They are not, however, a silver bullet for residential resilience. Permissionless batteries remain unaffordable and therefore out of reach for many Americans. Newer models can cost upwards of $1,000. When households need multiple batteries to provide greater levels of resilience, those costs can quickly add up. This is where the conversation about permissionless batteries needs to move beyond simply making batteries cheaper. The greatest equity opportunity for permissionless batteries is not replacing larger battery systems but complementing them.

While the cost of permissionless batteries may still be high for individual households, there’s an opportunity to reach economies of scale through mass purchase, for instance by housing providers or utilities, with the potential to be deployed at a large scale (think one battery per apartment or household). This is especially promising as it extends the benefits of energy resilience to renters, multifamily housing residents, and low- to moderate-income households that are often unable to install traditional battery systems, either due to cost or housing tenure.

Through Clean Energy Group’s Technical Assistance Fund, we’ve supported dozens of multifamily affordable housing providers in developing solar+storage systems that support the facility and medically vulnerable residents. The most economical solution has almost always proven to be providing backup power to a common area that can serve as a central resilience hub for residents, rather than backing up the whole building or powering loads in every unit.
This reality is not surprising. Larger batteries, multiple batteries, and the electrical upgrades required to support whole-building resilience can make the economics challenging. At the same time, relying entirely on a centralized system (like a resilience hub model) leaves residents without the ability to maintain essential loads inside their own apartments.

Permissionless batteries could help bridge that gap. Rather than choosing between comprehensive in-home resilience and a less expensive but less comprehensive central backup system, we can begin thinking about resilience as layered. Permissionless batteries can provide a minimal level of resilience inside the home, while larger solar+storage systems provide the capacity to power community-wide services.

Imagine, for example, a housing provider purchases permissionless batteries at scale and deploys one in every apartment, while also investing in a larger solar+storage system that provides backup power to the buildings common area in the event of an outage. Residents would gain a basic level of in-unit backup without having to purchase or install a battery themselves, while the building would retain access to a more comprehensive resilience resource.

The conventional affordability conversation asks us to choose between expensive, comprehensive in-home resilience and less expensive but more limited backup options. Permissionless batteries offer another approach: pairing modest in-home backup with larger, shared solar+storage systems.

This layered model could make resilience more accessible to households that cannot afford or install a traditional battery on their own, while allowing building owners and other institutions to invest in larger systems that provide more comprehensive resilience and economics benefits. The opportunity, then, is not simply to make batteries cheaper, but to rethink who purchases them, how they are deployed, and how the costs and benefits are shared.

Permissionless batteries are emerging as a promising new solution for reducing energy burdens and improving household (and grid) resilience. While promising, technology innovations alone will not close the resilience equity gap. How permissionless batteries are deployed and financed will ultimately determine whether they become a meaningful equity and resilience tool—or simply another valuable technology that remains out of reach for the households that could benefit from it the most.