Solar Power

Solar power uses energy from the sun to create electricity or pre-heat water for your home. Solar panels and water heating systems allow you to create clean, green energy, help to reduce climate change effects and could save you money.

Which technology is right for you?

Different green energy technologies are more suited to some types of homes than others. Find out whether solar power is right for you, or whether you should be considering another technology, like wind power or micro-combined heat and power. The Energy Saving Trust's energy generation selector can help you do this.

Solar panels

Solar photovoltaic (PV) systems are often known as solar panels, and use energy from the sun to create electricity. PV requires only daylight, rather than direct sunlight, to generate electricity.

How solar panels work

When light shines on a solar panel, it creates an electric field across layers of silicon in the cell, causing electricity to flow. The greater the intensity of the light, the greater the flow of electricity is. Power can be used straight away or linked back into the power grid.

Installing solar panels

You can use PV systems for a building with a roof or wall that faces within 90 degrees of south, as long as no other buildings or large trees overshadow it. If the roof surface is in shadow for parts of the day, less electricity will be produced.

Solar panels are not light and the roof must be strong enough to take their weight, especially if the panels are placed on top of existing tiles.

Solar panels come in a variety of shapes and colours, including:

grey 'solar tiles' that look like roof tiles
transparent panels that you can use on conservatories or glass to provide shading as well as generate electricity

What solar panels cost

Most domestic systems are between 1.5 and 3 kilowatts (kW) andcan produce around half a domestic property’s electricity requirements.

Solar tiles cost more than conventional panels, and panels that are integrated into a roof are more expensive than those that sit on top. If you intend to have major roof repairs carried out, it may be worth considering PV tiles, as they can offset the cost of roof tiles.

How solar panels can save you money

Producing your own energy could be cheaper than buying it from energy companies.

If you generate electricity using solar panels, the Northern Ireland Renewables Obligation entitles you to claim Renewables Obligation Certificates (ROCs) for every megawatt hour of electricity you generate.

ROCs can then be sold to electricity supply companies.
In addition, as a microgenerator you can enter into an agreement with NIE Energy to sell any electricity to them that you do not use.
NIRO - how it works
NIE Energy website

Planning permission

You may have to get planning permission to fit a PV system, especially in conservation areas or on listed buildings. Always check with your divisional planning office about planning issues before you have a system installed. Obtaining planning permission after the system is in place can be difficult and expensive.

Maintenance

Systems that connect to the grid require very little maintenance. You just need to ensure that the panels are kept relatively clean and that shade from trees isn't a problem. The wiring and components of the system should be checked regularly by a qualified technician. Stand-alone systems (not connected to the grid) need maintenance on other parts of the system, like batteries.

Solar thermal hot water

Solar thermal systems use energy from the sun to pre-heat water for your hot water or space heating needs. There are two types: solar tubes or solar flat plates.

How solar thermal hot water works

For domestic hot water you will need:

solar panels
a heat transfer system
a hot water cylinder

Solar panels - or collectors - are fitted to your roof and collect heat from the sun's radiation. When water is passed through the solar tubes or plates, it heats up and is then pumped into your hot water cylinder or boiler. The heat transfer system uses the collected heat to heat water. A hot water cylinder stores the hot water that is heated during the day so you can use it later.

A system can usually provide all your hot water needs during summer, and about half of your needs during the rest of the year.

Installing solar thermal

Preferably, you need three to four square metres of southeast to southwest facing roof, which receives direct sunlight for the main part of the day. You'll also need space for an additional water cylinder, if required. Always check with your local authority about planning issues before you have a system installed.

Benefits

Installing solar thermal hot water could save you up to £40 per year on your hot water bills, according to the Energy Saving Trust.

Maintenance

Solar hot water systems generally come with a ten-year warranty and don't require much maintenance. You should check the system each year and have a professional installer conduct a more in-depth check every three to five years. Ask your system supplier for exact maintenance requirements.