Solar panel installation is becoming increasingly commonplace, and within the next 20 years, most households will have some form of solar panel system. The technology behind solar panels is relatively straightforward, but it can appear daunting at first.
However, it’s important that we understand a bit more about it, in the same way that it’s important that you understand a bit about the electrics in your home, or how the water works. Here, we are going to introduce you to the various components of a solar panel system. If you have a solar panel installation, these are the bits of kit they will install.
Solar panels: the most important piece of equipment within the system is the solar panels. There are a number of different types of solar panel, but most are PV cells. PV stands for photovoltaic, and what this basically means is that when light hits the cell it creates voltage (or electricity – a volt is a measurement of electromotive force; don’t worry about the technicalities at this point). PV cells require direct sunlight, so in the UK they work best on south facing roofs.
Mounting brackets: This housing secures the panels to the roof. It is relatively heavy, and so you need to have the roof surveyed to make sure that it is structurally sound enough to support the mounting. Usually, with a solar panel installation, they have their own chartered surveyor look at the roof, but do double check that they have carried out the survey before you agree to the installation.
Wiring: this is self-explanatory. There are numerous wiring components. The solar panels need connecting to each other as well as other items, such as batteries, charge controllers, inverter and junction boxes. There’s a surprising amount of wiring.
Batteries: not all systems will have batteries, but some do. Often, the off-grid systems have batteries but the grid-tied systems don’t. Off-grid means that the electricity is not connected to the mains so doesn’t go back to the national grid. Grid-tied refers to solar panel systems that link to the national grid. With the grid-tied systems, any surplus energy goes back to the grid, but with an off-grid system, it is stored in batteries.
Charge controller: the charge controller controls the electricity stored by the batteries. It helps to prevent it from draining unnecessarily; it also prevents it from over charging. There are a number of different features offered by a charge controller, and this differs between brands and models. The better the model, the more features it offers.
Inverter: an inverted is a piece of equipment that changes the current of the electricity generated from direct current to alternating current. We need inverters because our electrical equipment (e.g. fridges, laptops, TVs, etc.) run on alternating current.
Grounding tools: it’s important that the solar panels be grounded correctly. If they aren't, then they can cause a fire hazard. Grounding tools simply ground the electronics where required.