How Much Electricity Does the Average Solar Panel System Generate?

  • A typical residential solar installation working at peak efficiency will provide up to 3400kWh of clean energy per year.
  • A residential solar installation will save you money on your bills and earn you money through the feed-in tariff.
  • To start generating your own power join the thousands who have used The Eco Experts expertise, simply fill out the form at the top of the page and receive quotes from local MCS accredited installers to you.

How much electricity can solar panel systems generate?

Each solar panel system is different, so to give you the best idea of just how much electricity can be generated, let’s take a look at the facts for average domestic solar panel systems:

  • Domestic systems tend to range from 1 kilowatt (kW) to 5kW in size.
  • Each 1 kW system can produce roughly 850 kW units per year so a 2kW system would create around 1,700 kW units and a 5kW system would create 4,500 kW units.
  • The Energy Saving Trust estimates that a typical 3-bedroom house in the UK would use just over 3,000 kW units in a year.
  • However, the Feed-in Tariff pays the highest rates for systems smaller than 4kW.

    Approximate Roof Space

    Typical System Size
    Estimated Cost
    Estimated Annual Output

    Estimated First Year Total Return

    Profit Over 20 Years

    8 m2
    850 kWh
    14 m2
    1700 kWh
    2550 kWh
    28 m2
    3400 kWh

    Use our solar pv calculator to discover how much electricity your home could produce using solar.

    What factors will determine the amount of electricity that I can produce?

    There are 3 key factors that will determine just how much electricity you can create with solar panels for your property:

    • The size of the system is the most important factor of all. The typical domestic installation is a 3.5kW system, which is normally around 12 panels, whereas the smaller domestic system 1kW is more like two panels.
    • The direction that your roof faces and the angle of the roof comes next. For optimum performance, your panels will need to be on a 35-degree angle, facing south.
    • Shading or lack of shading will increase the amount of electricity you are able to produce. Take a look at the handy table above, which shows you what output volume can be expected from a domestic solar installation.

      Do solar panels work in the UK climate?

      Let’s hand you over to the founder of The Eco Experts who knows everything there is to know about generating electricity with Solar Panels in the UK climate.

      Compare solar prices in your area

      Efficiency of the Solar Panels

      There are a few factors that can affect the efficiency of a solar installation on your property. No doubt your installer will be more than happy to give you an idea of the output that you, personally, can expect. But for now, here are some general key factors that you should be considering:

      The direction they face and the angle of the roof
      The positioning is crucial for successful solar panel installations in the UK. Those that are south facing are considered best, although they can be very effective facing south-west and south-east respectively.

      It is a common misconception that solar panels work from the sun’s heat. In truth it’s actually sunlight that is most important. By large, solar panel systems need to be installed a few inches above the roof, allowing enough air flow to cool them down. But this is less important in the UK where the climate is often cool, so it works to our advantage.

      In essence the less shade the better. If it is possible to install your panels where there is no shade, then you will certainly make the most out of going solar. You can always ask your installer to give you an assessment of how shade will affect your properties solar performance, if you are unsure.

      Your panels will need to be cleaned and maintained, but this is neither a frequent nor complicated process, and it won’t cost you an arm and a leg either. Chat to your installer about a complete service package and you’ll get a good idea of price.

      There is certainly a lot to consider before you decide to invest in solar panels, but it need not be complicated. Below we’ve listed some further on the Feed-In Tariff (FIT), which should be an important factor in making your decision.

      What is the Feed-in Tariff?

      The Feed-In Tariff is the government’s incentive to encourage solar installation and accelerate investment in renewable energy. Started in April 2010, FITs mean that you will be paid a set rate per kWh of electricity you produce.

      The exact rate that you will receive is based on several factors, but primarily it is the size of your system and the date you have it installed that matters.

      Have a look at the table below, which shows you the current solar tariffs from April 1st 2014. Note that the FIT scheme is reviewed every three months and that tariffs are set for the coming period. This alters the rates on offer for those time frames. Generally the FIT will apply from the time you apply for it, not necessarily the time your panels are installed.

      It’s also worth knowing that you can sell any electricity that you do not use back to the grid.

      Band (kW)
      Generation Tariff from 1st July 2015 (p/kWh)
      4 or less
      4 - 10
      10 - 50
      50 - 100
      100 - 150
      150 - 250
      250 - 5000
      Stand alone
      Export Tariff

      How do I qualify for the Feed-In Tariff?

      The qualification criteria for the Feed-in Tariff is very straight forward:
      • You must be the homeowner to guarantee qualification. If you rent, then you must speak to the property owner first.
      • Your home must have an EPC rating of Band D or higher. If lower, you’ll be on a slightly different rate.
      • To qualify for solar panels, your property must be south facing (but it’s worth noting that if your property is south-west or south-east, it may still be suitable).
      • And don’t worry if you already have had a solar panel since before the scheme began. If you've had an installation since July 2009 you can still join, and if before July 2009, you can too but at a lower tariff rate.

      Can I maximise the amount I save?

      Energy Saving Lightbulb You don’t need to be rich to go solar. The growing affordability of domestic solar installation, means that many more people can now benefit from lower electricity bills, and even earn money from FITs.

      However, there are a few basic things that we would recommend you do to your property, so that you make the most out of the electricity that your Solar PV installation produces.

      Here are a few tips from The Eco Experts:

      Make sure you shop around for the best energy provider
      The prices of electricity are rising, so make sure that you everything about what your supplier can offer, and what they guarantee you in the long run. Take a look at comparison sites, and make use of the great free tools available on the web. Customer reviews are an excellent way to do this, and you shouldn't have to search too long before you are able to find an honest assessment of an energy supplier you’ve been looking at.

      See what you can get for free
      Some large companies will offer you free insulation and boilers to get you to switch supplier. However, remember that the quality of the boiler and insulation is what really saves you money in the long run.

      Do the basics
      Most people are aware of the benefits in energy saving bulbs and being conscious of switching devices off at the mains. But what about exporting the electricity that you don’t produce and selling it back to the grid? This will become even more beneficial for you.

      Know your export tariffs
      In addition to FITs, as a homeowner, you are entitled to receive an export tariff. This is currently 4.64p for each unit of electricity that is sold back to the grid. You can also make savings on general energy bills, which makes going solar all the more attractive.

      What else should I consider?

      Solar Panels
      • No doubt installation costs are a worry to you, as is the way for many people. Although the cost has fallen substantially, it is still around £6500 for the average 3 Kw domestic installation. But bear in mind that this will repay itself over a period of time. There are schemes that offer free solar panels, but consider that the installer will keep the Feed-In Tariff.
      • Consider the period of time you intend on staying at your property. It’s important to get the most out of the Feed-In Tariff, so you will want to be sure that you intend to stay in your property for several years at least. Although you will benefit from lower energy bills from the beginning, which is an added bonus, as you can imagine the advantages of lower energy bills for the future.
      • Ensure that you are realistic about what you can earn from your property. The only way to truly understand your homes potential is to have an installer survey your home properly. Remember, that this can be done for free by completing the form at the top of this page.

      Is it worth installing the panels?

      It’s clear: solar panels can and will help you reduce your energy bills, as well as earn you money through the Feed-In Tariff scheme. The average domestic installation may not be enough to produce enough energy to make your home completely sustainable, but it will produce enough electricity for you to see a significant reduction in your bills. Plus over 20 years, your solar panels could earn you, on average, up to £12,819, tax free and index-linked, over 20 years.

      With this in mind, it is definitely worth you considering solar energy as a serious alternative to rising energy bills.

      If you are interested in lowering your energy bills, cutting your Carbon emissions and earning money with the Feed-in Tariff, complete the quick form at the top of the page and start your solar journey.