Questions about solar energy?

An 8-panel system is one of the smallest we recommend, which can normally fit on the roof of an average 3-bed semi-detached house.

Solar panels vary greatly in efficiency, so while one panel may generate 250 watts, another same-sized panel of a different brand may generate 345 watts. As you can see, it’s not a question of how many panels you need but how much power you need. Domestic solar systems usually aim for 4kWp, meaning 11-15 panels, depending on your chosen brand.

No. Solar panels work best on any roof facing South, SE or SW, although they will still perform at 86% (compared to South facing) either facing East or West.

Yes. Solar panels work in all daylight conditions and actually work best at 10ºc. In fact, if it gets too hot, they start to become increasingly inefficient.

There are a lot of solar panels to choose from, and most people look at aesthetics, price, value for money, performance, track record and guarantees. Our team can advise you on panels that suit your needs.

All solar panels come with a manufacturer’s warranty. Different manufacturers offer different warranties and they usually a standard 2-year parts and labour, and 10–20-year product warranty. It is worth knowing you can often buy an extended 20-year warranty for as little as £300. Our team will help you understand the warranties before you buy.

You should expect your panels to last for at least 25 years. Considering that the average life expectancy of a boiler is between 10-15 years, we think this isn’t bad! And solar panels don’t simply stop working after 25-30 years. They will continue to produce electricity, however, at a lower rate due to panel degradation. In fact, panels are designed and continue working way beyond their warranty period. The part that often needs replacing first is the only moving part of a solar PV system – the inverter. But even so, an inverter should last for over 10 years and may cost up to £1,000 to replace.

The term “Rate of Degradation” describes how a solar panel loses efficiency and power output over time. Solar panels often degrade because of long-term exposure to UV rays and adverse weather conditions. High temperatures and warmer climates are likely to increase degradation rates. However, extreme cold weather, heavy snow and wind affect solar panels the most. Lucky the UK isn’t usually exposed to extreme weather such as heatwaves, snowstorms and hurricanes. Panels in our moderate solar-friendly climate should retain 96% of their generation capabilities even after 20 years.

Most domestic solar installations take one to three days but some commercial installations can take a little longer, depending on the requirements.

In most cases, no. Domestic solar panel installations are ‘permitted developments’ and don’t require planning permission unless you want a ground-mounted array or you live in a listed building or a conservation area / an area of outstanding natural beauty. If you’re unsure about permitted developments, please visit the Government’s planning portal Planning Portal.

No. The team at OHM Energy will do that for you.

Solar panels are generally self-cleaning if positioned at an angle of over 15 degrees. However, we advise inspecting them annually and rinsing them if necessary. There are specialist solar panel cleaners and some window-cleaning companies have a reach-and-wash system that can clean your panels.

It is recommended that your solar panels are checked and serviced every year. We offer a standard service and maintenance package, which our team can talk you through.

The most common and standard installations on homes are either ‘in roof’ or ‘on roof’ which have  brackets that fix to the rafters (for on roof, or to the battens within roof) of your roof to ensure that the fabric is free from the weight of the panels.  Commercial roofs vary in construction and there are many different mounting options. Our team is used to dealing with complex or unusual installations and can advise you on options.

The electricity produced by your solar panels is converted from DC (direct current) by the inverter to AC (alternating current), which your premises (including commercial) is run on. An AC cable then takes the electricity to your distribution board, which powers the circuits in your home or business.

No. Solar panels only produce electricity during daylight hours. To live off-grid, you need a battery system to store your solar power for nighttime electricity. OHM Energy can advise and supply you with a battery system if you are interested in living off-grid and becoming energy independent.

No. For the safety of workers who may be repairing the electrical fault, your inverter will shut down. Some battery storage systems allow you to have backup power in the event of a power cut, so if this interests you, we’ll be happy to put together some options for you.

If you want to be paid for any excess electricity you generate, you must have a smart meter as well as battery storage. Most electricity suppliers install them free of charge for customers if you don’t already have one.

No. The FiT scheme finished in March 2019 and has been replaced by the Smart Export Guarantee (SEG) where you are guaranteed payments for any excess electricity you generate and sell back to the grid.

The Smart Export Guarantee (SEG) pays solar panel owners for electricity they have generated at home and put into the grid. All energy suppliers with more than 150,000 customers have to offer a SEG tariff. Smaller companies can choose to do so and some companies besides traditional energy companies have begun offering tariffs as well (including Tesla and Social Energ. Each company sets their own tariffs, so you’ll need to shop around to make sure you get the best price.

Not any more. Since the end of the Feed-in Tariff, any property with a solar installation does not need to have an EPC, though installing solar should enhance EPC ratings.

With recent energy price increases, we are seeing paybacks as short as 3-4 years for some systems across the home counties. Not bad when you consider the lifespan of most solar panels!  This element is very much decided on the current energy prices which fluctuate, please speak with one of our team about current prices and expected paybacks.

As of June 2022, no, but there are Export payments for surplus generation for Domestic installations, There are also various tax benefits and funding rounds for commercial installations.  Contact the team for the most up to date information.