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The key facts about solar PV

Solar panels systems come in two types called either solar PV or solar thermal. This section is about solar PV. These are panels that generate electricity. The other type of system (solar thermal) generates heat in the form of hot water.

The technology

Solar PV stands for solar photovoltaic. This just means the panels turn sunlight into electricity. You can find out much more about the detail at The Energy Saving Trust

The key parts of a PV system:

  • The PV panels. These collect the sunlight (even on cloudy days) and turn it into electricity.
  • The roof base. These are the aluminium rails and the roof anchors that are attached to your roof. The solar panels are attached to the roof by the base.
  • The inverter system. The solar panels are connected to the inverter by cables.The inverter is a sophisticated box of electronics that converts the electricity from the panels into a form that can be used by the electrical equipment in your house. It’s the “brains” of your system. The inverter also controls how any excess electricity is feed into the national power grid. Almost certainly your panels will produce more electrical power than you can use. The inverter will detect when this happens a feed all excess power into the national power grid. It does this via the cables that connect your house to the power system. There is a lot of safety built into the inverter. All the inverters we use have been tested by the power companies.
  • The generation meter. Last but not least is the meter. This is separate to your electricity meter. This measures how much electricity you generate from the panels. Your electricity supplier will pay you for every unit of electricity you produce. The amount you get paid is known as the feed-in-tariff. You can find out more about feed-in-tariffs on the Government’s official site here. So you will be paid to produce electricity! In fact your system becomes a mini-power station. It gets better. You will also be paid for the units your inverter feeds into the grid. The price you get paid for these units (by your electricity supplier) is known as the export tariff.

The finances

BES Co-op designs and installs your system. The price we charge includes everything you will need. This includes all equipment, installation, scaffolding, roof surveys and energy performance certificates.  There are no hidden charges.  Remember we are owned by our customers.
Once the system is installed and paid for we register the system with a local electricity supplier. This is usually the company that supplies your home. But you can choose any supplier you want. We can recommend the best one.
As soon as the system is registered your house becomes just like a power station. But one you control and one that does not produce any pollution. Each quarter you read the generation meter; email (or post) the readings to the electricity supplier. And - lo and behold – your electricity supplier sends you a cheque for all the electricity you have generated and for the excess electricity they think you have sold to them.
These payments are guaranteed for 20 years. Each year both the feed-in-tariff and the export tariff automatically increase in line with the retail price index.
So for the next 20 years you get a cheque from the electricity company!
For a quick check, click on our solar checker to see if solar PV will work for you.

And it gets better

All the income you generate from both the feed-in and export tariffs are tax free regardless of your personal tax rate.
And your electricity bills get smaller. Because you are using some of the free electricity generated from your panels to run equipment in your home you will buy less electricity form your electricity company making your electricity bills smaller. Your bills will be smaller for as long as you keep the panels running. This is likely to be for a lot longer than 20 years.
BES Co-op provides an additional financial benefit that no other solar panel provider in the district does. As a customer of the co-op you have a right to share in the profits of the company. So at the end of each successful year you can demand a dividend payment back from your co-op.
BES Co-op provides an additional financial benefit that no other solar panel provider in the district does. As a customer of the co-op you have a right to share in the profits of the company. So at the end of each successful year you can demand a dividend payment back from your co-op.

Where’s the catch?

Once the system is up and running there are very few.
The system needs little maintenance. If installed correctly the panels clean themselves (from rainfall); but might require a wash down from a hose pipe every 5 or so years. BES Co-op will be providing a (paid for) maintenance service if you want it. The main thing to watch out for is the invertor. This is the brains of your system. They have no moving parts but are complex. They can go wrong and are expensive to replace. All BES Co-op inverters are guaranteed for at least 5 years (some for longer). So it’s a better deal than you get on a new car. And just like a new car inverters can go on running for many many years. Unlike a new car they don’t need any annual maintenance. But inverter prices are falling so we’d expect them to become much cheaper in the future (a bit like home computers do).
The biggest pitfalls are in the up-front design and installation of the system. To get the best return from your investment the system must produce the maximum amount of electricity and must not be too expensive.

This is where BES Co-op comes in...

A number of things determine how much electricity your system generates. Here are the really important ones.

  • The sort of panels and invertor used. The efficiency of panels and inverters vary. Also some panels work better with some inverters. So it’s important to choose the right type and the right combination of panels and invertor. Don’t worry about this BES Co-op will do it for you. We are constantly reviewing new panel and inverter types and making the best choices for our customers (and our members).
  • Which way your roof faces. The closer to south your roof faces the more sunlight it gets. There’s not much you can do about it. But if your roof faces somewhere between south west and south east it’s worth looking at solar panels.
  • How strong your roof is. The panels and roof base can weigh up to 30kg per square metre. So large system will put additional stress and strain on your roof. On windy days these will increase. Snow will also increase roof loads. Almost all roofs in the UK are strong enough for solar panels. But care must be taken to make sure the roof base is attached to the roof securely and safely. BES Co-op carries out a structural survey before installing a system. The structural engineer might recommend roof strengthening. BES Co-op will do the structural survey and carry out strengthening if required. Don’t worry we’ve done this before. And often is not that expensive (an additional £150 is typical). We won’t carry out any work without getting your agreement first.
  • The pitch of your roof. This is how steep your roof is. If it’s either very shallow or very steep it won’t get much sunshine. Again there is not much you can do about it but the ideal angle is between 30 and 40 degrees.
  • The degree of shading. When the panels are shaded they don’t produce electricity. Indeed in badly designed systems shaded panels can stop the entire system working. Shading from nearby trees, from chimneys and flues all need to be considered when working out the best place to put the panels. This is not something you need to worry about. BES Co-op will put the panels in the optimal position.

All this sounds complicated; and for someone new to solar systems it is. BES Co-op are experts.
Before you decide on which system to have BES Co-op will carry out all the necessary surveys and design work. We use the latest software to design the system and roof layout.

The Investment

Most people install solar systems both for additional income as well as for environmental reasons.
Buying a system that is well designed is important (as described above). But it must also be good value. If the price is too high it may be better to put your money into a savings account. If it is too low that might be because the system uses cheaper, less efficient, panels and inverters and therefore won’t generate as much electricity. Find out more by visiting our solar calculator page.  This will give you a guide to how much a solar system from us might cost and how much electricity it could generate.  Our prices include VAT, design, installation, scaffolding, surveys and Energy Performance Certificates. There are no hidden extras. 

See if solar will work for you with our online calculator

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