Solar panels? Is the Solartwin solar water heating system suitable for me?
Solar energy direct for your home – checklist – considering to buy solar water heating systems in UK / Ireland…
- Yes, you get the best solar water heating system performance if you can face the solar panel mainly unshaded, roughly towards the sun. Solar water heating panels on south, southwest or southeast roofs are ideal. Even east or west roofs usually offer 75-85% of peak performance from a solar panel.
- Easily, if you have a traditional low pressure vented hot water system. This means a hot water cylinder, with its cold tank above, usually in the attic. Thermal stores are an easy fit, too.
- Yes, if, height-wise, there’ll be under 5 metres height (up or down) between the water level in the cold tank and the solar panel’s midline. OK in most homes.
- Yes, if your hot water cylinder holds over 80 litres. Most are about 120 l.
- Listed buildings, conservation area properties, national parks etc, may need consent for solar panels. Solartwin is normally viewed as a roof window by planners.
And high pressure solar plumbing options? Solar water heating solutions for high pressure hot cylinders or combination boilers may also be feasible using thermal stores. Please call us about thermal stores on 0845 1300 137
How many Solartwin solar panels do I need? In UK/Ireland one 2.8 sqm solar hot water panel is the usual number in homes of 1-4 people.
Who uses Solartwin solar thermal systems? Want to do something significantly positive for the environment? Or do you use costly fuels, or live “off-grid”? Homeowners, self-builders, pool owners, farmers, businesses and housing associations (eg. Berwickshire, Perthshire, South Yorkshire, Habinteg, Bournville Vilage Trust) use Solartwin. Some solar case studies are here.
Is the sun OK in UK or Ireland? Yes! (Spain can use smaller panels.) Specifically designed for Scotland, Solartwin also performs superbly in hot countries. It typically gives 30-70% of a home’s hot water a year and works in response to variable sunlight levels. Meteorologists say the June sun offers 6 times more solar energy than December’s. All solar water heating systems outside the tropics always need some top-up heat (eg gas, wood, oil, electric), most in winter.
What about other uses of solar panels, apart from washing and bathing (which are usually the best solar applications)?
We recommend that providing solar hot water for washing and bathing are optimal applications for solar heating (of any technology) in relatively cool climates such as UK and Ireland. In general, solar hot water uses for washing and bathing are usually preferable to solar central heating or solar electric installations. These recommendations are based on based on either “usability fraction” or “cost-benefit reasons”, as follows…
- Solar central heating It’s cold in winter and at night because of the lack of sunlight. Unless you want radiators at full blast on sunny summer days, solar washing & bathing offers at least 2-3 times better value.
- One Solartwin solar panel installation delivers around 2-5 times more energy than the same sum of money spent on a solar electric (photovoltaic) array.
Need I control water hardness?
Control for “direct” Solartwin solar water heating system installations is uncomplicated. First phone the water company for “parts per million calcium carbonate” (also called “ppm CaCO3”). If they quote one figure instread to a range (not two) figures, allow 20% tolerance i.e. add 20% to their figure i.e. treat a single figure of 200 as 240.
- If hardness ever exceeds 200 ppm CaCO3 (very hard water) use either an ion-exchange (salt-regenerated) water softener or an “indirect” Solartwin. We supply and fit softeners. Please call.
- At 100 – 200 (maximum) ppm CaCO3, you can use Fernox Superconcentrate Limescale Preventer. Your first little bag of crystals on a string is free. Simply hang it in the cold tank. Replace it twice a year. A free 6-monthly postcard reminds you. Fernox SLP is food grade. It costs about £10 from DIY shops. Or you can use an ion-exchange water softener or an “indirect” system.
- Under 100 ppm, and with “indirect” Solartwins, use no hardness control.
All other water hardness treatments or conditioners, including electromagnetic, magnetic, electronic, physical or ultrasonic methods must not be used. The above 200 ppm maximum thresholds are reduced to by a further 20% for all “fortic” type hot water cylinders as well as irregularly used hot water systems, such as in holiday homes.
Yes, Solartwin cuts global warming!
Solartwin not only saves energy and money. One single solar panel Solartwin solar water heating installation in UK or Ireland can cut your yearly carbon dioxide emissions by a quarter of a tonne if your water heating fuel is mains gas. If other fossil fuels, or electricity are saved then yearly saving can be up to a tonne or more!
Solartwin – for energy systems designed with you and our environment at heart. Time for a solar roof?
