Renewable Energy Options

Fossil fuels are not the only available means of providing energy for your home. There are many kinds of renewable energy, which provide a viable alternative energy source for household use. The benefits of renewable household energy include;

• Security of supply
• More environmentally friendly
• Reduction of external energy bill

Below is a list of the key home renewable energy options, some that provide heat and others that provide electricity. To find out full details on renewable energy for the home, visit the Sustainable Energy Authority of Ireland website.

Solar Hot Water Systems

Solar collectors (panels), typically roof mounted, convert sunlight into heat. This heat is normally used to provide hot water, but can also be used to provide space heating in a combined system.

There are two standard types of collector: flat plate or evacuated tube. An appropriately sized solar water system can provide you with 50-65% of your hot water requirements. Solar hot water systems need to be supported by a conventional heat source to increase water to usable temperatures. Such systems include a boiler or an electric immersion heater. Solar thermal systems are easy to install and are reliable, although a professional installer is required.

Life Expectancy: about 30 years
Payback Period: 8-20 years

Photovoltaics (PV) for electricity

Photovoltaic solar cells convert sunlight directly into electricity. They can be installed on an existing roof, or on a nearby structure. Alternatively, they can be moulded into solar slates or solar tiles for integration into roofs or bonded onto glass or metal sheets for incorporation into architectural glazing and fascia systems. Different types of PV technology exist that use different materials and manufacturing techniques, with conversion efficiency ranging from 8% to approximately 20%. PV solar cells are expensive but safe and reliable and require minimum maintenance.

Life Expectancy: 25-30 years
Payback Period: 20 years

Ground Source Heat Pumps

Ground Source Heat Pumps (GSHP) can be used for space heating and cooling, and for water heating. Ground heat pumps obtain energy from several metres below the surface of the earth. The energy is then transferred from a series of pipes in the ground to a heat pump and a distribution system such as radiators or an underfloor heating system. Geothermal heat pumps are one of the most energy and cost efficient methods of home heating and cooling, provided the building has adequate space for installation. Given the costs associated with installation in an urban environment due to space limitations, this method may be more suitable for newly constructed housing, where sufficient space can be incorporated at the planning stage.

Life Expectancy: About 20 years
Payback Period: 8-15 years