If you have not come across plug-in solar before, the idea can sound almost too simple. Panels in your garden or on your balcony, a cable into a wall socket, and your electricity bill goes down. It really is roughly that straightforward, but understanding the components helps you make a better buying decision and know what to expect from your system.
What comes in a typical kit
A standard plug-in solar kit contains three main things: one or two solar panels, a microinverter, and a cable. Some kits include mounting hardware. Higher-end systems may add a smart meter clamp or a battery storage unit.
The solar panels are the same photovoltaic technology used in rooftop installations, just smaller and usually designed to be mounted vertically or at a shallow angle on a balcony railing, fence, or wall bracket. Most panels in plug-in kits are either 400W monocrystalline panels, meaning a full 800W kit uses two of them.
What the microinverter does
This is the component that makes the whole thing work. Solar panels produce direct current (DC) electricity. Your home runs on alternating current (AC). The microinverter converts the DC output from your panels into AC that is compatible with your home’s circuits.
Critically, the microinverter also synchronises with the electricity already flowing through your home from the grid. When you plug in the system, it detects the existing current and matches it precisely, so the solar power blends seamlessly with the grid supply. It also includes anti-islanding protection, which means it shuts down automatically if the mains power fails, preventing any risk to engineers working on the local grid.
How the electricity flows through your home
Once the system is connected and generating, the electricity your panels produce flows into your home’s ring main circuit through the socket. Any appliance running in your home draws from this mixed supply first before pulling from the grid. If your panels are generating 600W and your home is using 400W, the remaining 200W flows back out to the grid.
You do not need to do anything for this to happen. There is no switch to flick and no app to manage. The system works automatically whenever there is daylight.
Where can you put the panels?
The most common locations are a south-facing balcony railing, a garden fence, a flat roof, or a wall bracket. The panels do not need to be at the optimal 35 to 40 degree tilt to work, though output is highest at that angle. A vertical panel on a balcony railing will produce roughly 70 percent of what the same panel would generate at optimal tilt. That is still a meaningful amount of free electricity.
You need to be within cable distance of an outdoor socket or a socket accessible through a window or door. Most kits come with a cable long enough to cover typical balcony or garden setups.
Do you need any tools or technical knowledge?
The physical setup is genuinely simple. Attaching panels to a railing or bracket requires basic tools and usually takes an hour or two. The microinverter connects between the panels and the plug. Once you have notified your Distribution Network Operator under G98, you connect the plug and the system starts working.
The only technical step that currently requires a professional is the final electrical connection, which until the BSI product standard is published later this year should be made by a registered electrician. Once that standard is in place, the full installation will be legal to do yourself.