RENEWABLE ENERGY
Renewable energy is energy derived from natural sources that are replenished at a higher rate than they are consumed. Sunlight and wind, for example, are such sources that are constantly being replenished. Renewable energy sources are plentiful and all around us.
Fossil fuels - coal, oil and gas - on the other hand, are non-renewable resources that take hundreds of millions of years to form. Fossil fuels, when burned to produce energy, cause harmful greenhouse gas emissions, such as carbon dioxide.
Generating renewable energy creates far lower emissions than burning fossil fuels. Transitioning from fossil fuels, which currently account for the lion’s share of emissions, to renewable energy is key to addressing the climate crisis.
SOLAR PANELS (PV)
How do solar panels work?
A solar PV panel consists of many cells made from layers of semi-conducting material, most commonly silicon. When light shines on this material, a flow of electricity is created.
The cells don’t need direct sunlight to work and can even work on cloudy days. However, the stronger the sunshine, the more electricity generated.
Solar PV systems are made up of several panels, with each panel generating around 355W of energy in strong sunlight. Typical systems contain around 15 panels and generate direct current (DC) electricity. Because the electricity used for household appliances is alternating current (AC), an inverter is installed along with the system to convert DC electricity to AC. This electricity can be used throughout your home, or exported to the grid.
BATTERY STORAGE
Home energy storage systems store generated electricity or heat, so that you can use the energy when you need it.
Electricity can be stored in electrical batteries, or it can be converted into heat and stored in a heat battery. Heat can also be stored in heat batteries or in thermal storage, such as a hot water cylinder.
Energy storage can be useful for people who generate their own renewable energy, as it allows them to use more of their low carbon energy.
For example, electricity generated during the day by solar PV panels could be stored in an electric battery for you to use for boiling the kettle or watching TV in the evening when your solar PV panels are no longer generating electricity.
The battery size and its cost will depend on your current energy use and the size of any generation technologies you have installed. You may also want to plan around future electricity use if you are intending to purchase an electric vehicle (EV) or heat your home with a heat pump.
FAQ
Do I have enough space?
Space is a key consideration. The average system size is around 4.2kWp and this will typically take up around 25m2 roof area.
An unshaded, South facing roof is ideal for maximum electrical output. East or West facing roofs could still be considered, but North facing roofs are not recommended. A system facing East or West will yield around 15-20% less energy than one facing directly South.
Shaded roofs
Any nearby buildings, trees or chimneys could shade your roof and have a negative impact on the performance of your system.
Finding an unshaded spot is best, however sometimes shading is unavoidable. Some solar PV systems can minimise the impact of shading using ‘optimisers’. If you don’t have shading, the use of optimisers is not necessary or beneficial, other than the increased monitoring opportunities they offer – they won’t generate more energy.
Do I need planning permission?
Solar PV panels are considered ‘permitted developments’ and often don’t require planning permission. However, exceptions apply and it’s best to check with your local planning office for guidance.
If you live in a listed building, conservation area or national park, additional restrictions may apply.
If you’re planning to install a solar PV system in your home, you must register it with your Distribution Network Operator (DNO). The DNO is the company responsible for bringing electricity to your home. Usually, your installer will register the device for you.
For more information click on the Planning Info Tab below.
How much does it cost?
The average domestic solar PV system is 4.2kWp and costs around £6,500.
The amount you will pay is influenced by the size of array and will be affected by any difficulty with access to your roof. Some of the installation costs can be shared if you already have scaffolding up for roof repairs or if you are building a new house. Costs are also affected by whether you choose panels or tiles, and whether you opt for building-integrated panels or choose panels that sit on top of your roof. Panels on top of the roof are the cheapest option, while tiles are the most expensive for the equivalent system.
The cost of ground-mounted systems is more difficult to predict, as there are more variables such as the type of mounting frame, and how far away it is from the house.
Can I get paid for my excess Solar?
With any domestic PV system, there will be times when the electricity you generate is more than you can use or store, so the surplus will be exported to the grid to be used by somebody else. If you want to be paid for exporting, you need to make sure you’re getting an export payment. If you were able to claim the Feed-in Tariff (this closed to new applications at the end of March 2019), then you will be getting export payments as part of that. If not, you need to find an energy company that will pay you for this surplus.
Following the closure of the Feed-in Tariff scheme to new solar PV system applicants in March 2019, the Smart Export Guarantee (SEG) was introduced to provide financial support to small-scale renewable energy generators for the electricity they export to the grid. The savings from solar PV with the SEG are considerably higher than without it.
In Great Britain, the Smart Export Guarantee pays you for the electricity you generate.
In Northern Ireland, you can get paid for any surplus you export – usually estimated based on how much you generate. Several organisations offer this service, so if you’re interested, we recommend researching their offers to find one that works for you.