With over one million installations across the UK to date, it’s clear that there’s something attractive about solar PV.
By using the sun’s energy to generate electricity, you can save money on your electricity bills, as well as doing your bit to cut your home’s carbon footprint.
First and foremost, your roof’s got to be right for the job. South-facing roofs are the best as they get the most direct sunlight throughout the day. East and West can also bring good results, but if your roof faces North, it’s not the technology for you. Whatever way your roof faces, it has to be free from obstructions – this might mean shading from trees or nearby buildings.
If your prime focus is mainly on reducing the greenhouse gas emissions associated with your electricity supply, then solar will do that. A home solar installation can save about one tonne of carbon a year. And even if you’re not able to use all of this green electricity yourself, the excess electricity is exported so that someone else can use it.
But it’s important to do the maths. If looking at solar from purely an economic point of view, there are some key considerations to factor in. An average sized solar PV installation costs around £4,800.
The more you’re able to use the electricity they generate during the daytime, the better value solar is going to be. So, lifestyle matters.
By using a higher than average proportion of your electricity in the daytime, when the panels are generating electricity, you could save more on your electricity bills.
An average domestic solar PV system, installed in South England, with a family out all day until 4pm, is likely to save around £130 a year on electricity bills. If the family is home all day, this increases to over £270 a year.
If you’re retired, or planning retirement, and you’re likely to be around the house a lot, you’re likely to use more solar electricity, and make bigger savings. If you work at home – as many of us are now doing thanks to lockdown – or are a stay-at-home parent, a similar logic applies.
You could also sign up to one of the Smart Export Guarantee (SEG) tariffs available. A SEG tariff pays you for every unit of electricity you don’t use and export to the grid. Visit the Smart Export Guarantee page for details.
A family staying home all day, saving £270 on electricity bills and receiving a 3.99p/kWh SEG tariff for excess, exported electricity could see a simple payback on their £4,800 investment in 16 years.
Estimated paybacks for different areas in the UK, as well as if you’re home or out most of the day, are available on our solar PV page.
Installing solar when you’re already taking on other work can also improve the return on investment.
If you’re undertaking a loft conversion or changing your roof, scaffolding will already be up – an expensive part of installation that you’re likely to be able to deduct from the fee charged by solar installers. Skylights can also be placed in a way to ensure the most panels can be fitted. More panels, more electricity, more benefit.
If work inside the house is being undertaken too, as part of an extensive renovation, then it might be the time to fit low energy lighting and appliances, to make the most out of the free electricity.
Beyond the financial implications of adding solar to an existing job, there are clear convenience benefits. Disruption is minimised, and it may well be easier to run electrical wiring and connect to the grid while other work is going on.
Global demand means that the cost of solar panels has fallen over the last few years, and is likely to keep dropping in the future.
The technology itself will also evolve over time. The efficiency of solar cells is improving, and ideas that are currently in the lab may be on roofs within the next few years.
For those who aren’t so keen on the aesthetics of solar panels, solar tiles could be an option. At the moment, this is a significantly more expensive and less efficient way of doing things, but with tech companies like Tesla jumping into the market, big improvements are expected. There may even be a future role for entirely transparent solar windows.
For now, solar panels can still make sense for many homes. It’s all a matter of having a clear idea of what your motivation for investing is; and once established, finding practical ways to get the best out of an installation.