Plug-in solar set up on a balcony in Germany. Photo by Yuma Solar on Unsplash
When we think of solar, we often envision panels up on a roof or in a field. As it turns out, there is a simpler and smaller way to use solar panels that other countries have already figured out: plug-in solar.
Plug-in solar systems use solar panels and an inverter, which turns the DC electricity generated from the panels into AC electricity that home appliances can use. A plug comes out of the system, which you can plug into a wall outlet. When the sun is out, the electricity flows directly into your home’s wiring through the outlet. Your appliances will automatically use that power first, before pulling from the grid. A kit may also come with ground mounts for the panels to sit on so that they face the sun, or brackets to attach the panels to a balcony. The systems are typically under 2 kilowatts (kW), compared to a typical full-size residential solar system in the US, which is around 6-8 kW.
There are bills in over a dozen states to legalize plug-in solar, including in Vermont. Bill S.202 would make it so that plug-in solar devices would not need an interconnection agreement–a contract between the customer and utility that is used, for example, when a new rooftop solar system is connected to the grid. Eliminating the need for an interconnection agreement would reduce costs and waiting time. This bill was introduced by Senators Anne Watson, Seth Bongartz, Thomas Chittenden, Alison Clarkson, Martine Gulick, Ruth Hardy, Virginia Lyons, Kesha Ram Hinsdale, Tanya Vyhovsky, David Weeks, and Becca White. The bill passed in the Senate and has now been referred to the House Committee on Energy and Digital Infrastructure.
Plug-in solar is particularly useful for renters, people who live in condo associations, people whose roofs aren’t suitable for solar, and anyone who cannot commit to the high cost of larger rooftop or ground-mounted solar systems. In Europe, plug-in systems have been around longer, and regulations have caught up to their popularity. As a result, over one million households have registered plug-in solar devices in Germany alone.
The cost of a plug-in system in Europe runs around only $300. Vendors are just starting to bring these products to the US, and we as a country are in the beginning stages of regulating plug-in systems. In Utah–the first state to pass plug-in solar regulations–you can buy a kit for around $1,000. The cost runs closer to $2,000 if you include a battery. The amount you save annually depends on the cost of electricity where you live. According to the Vermont Natural Resources Council, the average Montpelier resident would save around $200 a year with a plug-in system.
Vermont climate Activist Bill McKibben is an advocate of plug-in solar systems and has pointed out the uses beyond cutting back on your power bill. A plug-in system with a battery is a defense against power outages, allowing you to keep your phone, internet router, and/or radio powered. He compares it to growing a vegetable garden, a kind of “hedge against trouble, and a reminder of your connection to the natural world.”
Interested in whether plug-in solar might be right for you? Keep an eye on Bill S.202. The Vermont Natural Resources Council (VNRC) and Vermont Public Interest Research Group (VPIRG) are good places to follow along for updates.