In the UK the  Energy Saving Trust (EST)  have been doing a  long-running trial of 88 solar hot water systems, also known as solar thermal systems.

Solar thermal panels use the sun to heat water in homes, rather than generate power, as solar photovoltaic (PV) panels do.

The UK trial shows that things like good  installation,  insulation of the pipes and water tank are all key in improving the performance of a solar hot water system, so you can save the most on your heating bills.

The trials found that solar hot water systems on average – normally provide 39 % of  all the hot water a home needs.  Which is probably somewhere between  £60-£90 savings on energy bills per year.

But  if the system is well installed and used correctly , it could provide 60% of the home’s hot water needs.  A badly installed and run solar system could provide as little as 9%.

Users need to make sure they are  insulating their tank and pipes, getting the right system size and setting up pumps and timers correctly.

Solar payback time

With solar thermal systems in the UK costing about £3,000-£5,000,  payback time is still a big issue -  issue and might explain why there aren’t many systems installed in the UK.

Those nice looking halogen downlighters in your home could be costing you hundreds of euros a year in elecricity. You could reduce your electricity usage by replacing the halogen bulbs with low energy LED bulbs.

The most common fitting for those spotlight type recessed downlights are GU10 fittings. Most halogen Gu10 bulbs are 50 watt bulbs – so a house with 20 of these lights would be using 1000 watts when they are all switched on.

If you had all these lights on for just 5 hours every day they would add €270 a year to your  electricity bill each year according to the ESB.*

You can buy these replacement  LED GU10 bulbs and 20 of those in use for 5 hours a day would use  just €22 worth of electricity a year.  That is a massive saving of 90%. A house with 20 of these halogen 50w Gu10 bulbs could cut their electricity bills by  €248 a year by switching to low energy 4  Watt LED bulbs.

That  is the equivalent (according to ESB) of using a vented tumble dryer 12 times every week (5kg load) all year.

The LED lightbulbs do cost   more than the halogen bulbs -  but in  less than a year you will start seeing a payback.
These LED bulbs last 10 to 15 times longer than ordinary halogen bulbs – so in the long term you will be even better off.
After 2016  Halogen bulbs will not be allowed at all under EU regulations.

You can buy these  LED GU10 bulbs online from Amazon with free delivery to Ireland – they fit straight into existing GU10 sockets and are exactly the same size. They are CE approved too.

These LED Gu10 Bulbs get good reviews too

* (Calculations as per the ESB online energy usage  calculator  based on  rates of 16.00c per Unit (including VAT) )

Grants are also available in Ireland for the installation of solar electricity panels.

Geothermal heating harnesses natural thermal energy from within the Earth’s crust for water and space heating. This method of heating is hailed for its energy efficiency, lack of pollution, and financial benefits.

A series of pipes are set up in a loop beneath the house and cooled water is pumped through. As the water passes through the ground, it conducts heat, which is then re-extracted in a heat exchanger below the house. The heat that the exchanger pulls from the water and the heat created as a by product of the exchanger’s work are used to heat the house.

By far the greatest benefit is cost. This form of heating costs a fraction of the price of conventional heating systems in use in Ireland today. Thanks to a low consumption of electricity and minimal maintenance costs, there is an energy saving of 70% in comparison to conventional heating systems. A geothermal heat pump reduces a home’s annual heating energy use by 50 to 70 per cent. In addition, the system can also reduce space cooling costs up to 40 per cent and domestic water heating costs up to 25 per cent.

The costs of these systems vary, but the cost of an 8KW heat pump and the outside pipes is generally around €16,000 in Ireland.

Your home’s windows, walls, and floors can be designed to collect, store, and distribute solar energy in the form of heat in the winter and  reject solar heat in the summer. This is called passive solar design or climatic design. Unlike active solar heating systems, passive solar design doesn’t involve the use of mechanical and electrical devices, such as pumps, fans, or electrical controls to move the solar heat.

Passive solar homes range from those heated almost entirely by the sun to those with south-facing windows that provide some fraction of the heating load. The difference between a passive solar home and a conventional home is design. The key is designing a passive solar home to best take advantage of your local climate.

You can apply passive solar design techniques most easily when designing a new home. However, existing buildings can be adapted or “retrofitted” to passively collect and store solar heat.

The Passive House concept represents today’s highest energy standard with the promise of slashing the heating energy consumption of buildings by an amazing 90%

A Passive House is a very well-insulated, virtually air-tight building that is primarily heated by passive solar gain and by internal gains from people, electrical equipment, etc. Energy losses are minimized. Any remaining heat demand is provided by an extremely small source. Avoidance of heat gain through shading and window orientation also helps to limit any cooling load, which is similarly minimized. An energy recovery ventilator provides a constant, balanced fresh air supply.

Direct gain is the simplest passive solar home design technique. Sunlight enters the house through the aperture (collector)—usually south-facing windows with a glazing material made of transparent or translucent glass. The sunlight then strikes masonry floors and/or walls, which absorb and store the solar heat. The surfaces of these masonry floors and walls are typically a dark colour because dark colours usually absorb more heat than light colors. At night, as the room cools, the heat stored in the thermal mass convects and radiates into the room.

An indirect-gain passive solar home has its thermal storage between the south-facing windows and the living spaces.

The simplest and most reliable sunspace design is to install vertical windows with no overhead glazing. Sunspaces may experience high heat gain and high heat loss through their abundance of glazing. The temperature variations caused by the heat losses and gains can be moderated by thermal mass and low-emissivity windows