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FOC ENERGY SOLAR WATER HEATING ,,,,,that doesn't cost the Earth "Average install now takes just 8 hours" Over 40 homes now installed!! Pictures Of Installations (51,Cheveral St, just added)
EVACUATED TUBE SOLAR HOT WATER PANEL These top-of-the-range solar panel heat collectors are suitable for heating domestic hot water, swimming pools etc - even in the winter! One unit is adequate for an average household (3-4people), and it is modular, so you can add more if required. A single panel is sufficient for a 200litre cylinder, but you can fit 2 or more for high water usage, or for heating swimming pools or under floor heating. Some types of renewable energy are only available in certain locations, however free solar heating is potentially available to almost every house in the UK! Every house should have one -really! And with an overall efficiency of almost 80%, they are much more efficient than electric photovoltaic solar panels (efficiency of 7-15%). And if we compare them on a like-for-like basis, the price of a FOC Energy Solar Water Heater is around 30p/watt (compared to £6+/watt for
This high tech unit concentrates the sun's energy at the tip of the copper 'heat tube' - like a solid state magnifying glass! The vacuum tube solar panel has been around for over 10years, and has proved to be reliable and dependable. The vacuum tubes consist of a double wall glass tube (made from strong borosilicate glass ie pyrex) with a space in the centre which contains the heat pipe. The sun's radiation is absorbed by the selective coating on the inner glass surface, but prevented from re-radiating by the silvered innermost lining. This is in effect like a one-way mirror which has been optimised for infra-red radiation. In fact it is very efficient, of the sun light's energy hitting the tube's surface, 93% is absorbed, whereas only 7% is lost through reflection and re-emission. The presence of the vacuum wall prevents any losses by conduction or convection - just like a thermos flask. Because of this, the system will work even in very low temperatures, unlike traditional flat plate collectors. This is why our system can be used to heat up water at the South Pole Antarctic Science Base - where ambient air temperatures can drop below -40°C
The heat transferred to the tip of the heat pipe is in turn transferred to a copper manifold in which water circulates to heat the domestic hot water tank. If a tube is placed in direct sunlight on a summer day, the tip temperature can reach 250°C - so the system easily heats domestic hot water cylinders to 60°C even in cooler weather! The manifold is heavily insulated with a 2" thickness of pre-formed rockwool to keep the heat in. Unlike flat plates, these headers are so well insulated that they should not require antifreeze in normal operation - the temperature of the header is unlikely to fall below 10°C even in very cold weather. The more advanced solar controllers include a low-temperature facility- should the temperature of the collector fall below a defined level, the pump will operate to allow the the water at the bottom of the tank to heat the collector slightly. In normal conditions, this would never be necessary - but it acts as a good safety margin. How Much Heat Will I Gain? Average Daily Irradiation (Isolation) Figures for Each Month of the Year: (Solar energy reaching each 1m2 of the earth’s surface at UK latitudes)
Solar Panel
Pressurised Systems. The drawing above is one example of how to connect the panel. This is a typical installation that would be carried out by our professional installers, utlising a twin coil solar cylinder. These cylinders are far superior to a standard domestic hot water cylinder - and I can supply these up to around 500litres capacity! Typical solar cylinders are 175 - 260litres. The additional water capacity allows the user to store heat for several days, to even out variations in day-to-day insolation. The diagram above shows how the solar loop can be operated as a pressurised system - this is almost universal for various reasons:
It depends on your application (survey on request). The simplest system would be based on thermo-siphon (convection or 'gravity feed'). The panel would be mounted lower than the hot water cylinder, when the sun shines, the hot water will rise, and displace the colder water which returns to the panel. This system requires no additional energy, no control system and is self-regulating, simple, cheap and effective - but not very convenient for most situations. In this case, you will only require the header tank or pressurised system kit plus copper tube and insulation.
Our typical system includes:
What about Swimming Pools? Swimming pools are an ideal application for solar water heating, as the temperature required is quite low - under 30°C. Most installers will recommend flat plates to keep the price down - because the amount of panels required is much larger than for heating domestic hot water - however, if you can buy a high efficiency evacuated tube solar panel for the same money - you might as well enjoy solar heated pool water all year round - instead of just in July and August! If you used flat plates, a rule of thumb for calculating what you need is to fit the equivalent of 50% of the pool's surface area. For Vacuum tube panels, this is reduced to 25% - and of course, they will carry on working in the autumn, winter and spring. The FocEnergy panel is 2.25m2 so each panel will heat 11m2 of pool area. A 40m2 pool would only need 4 FocEnergy panels (and we will give you a discount on 4 or more!). Compare this to the cost of heating a pool for a year! Installation is very simple. If you have chlorine we will need to fit a stainless steel heat exchanger (this is because chlorine causes copper to corrode). If you dont have chlorine, we can simply put the solar panel in-line with the pool filter, so that the pump directs water through the panel before returning it to the pool. As the panel will NOT radiate heat on cold days, heat losses will be confined to your pipe runs only - so you do not necessarily need a controller, although one can be fitted, to control a 3-way solenoid valve to divert the water through the panel when the panel is hotter than the pool water.
A Word on Flat Plates Flat plate collectors only provide a useful amount of heat during the summer months in the UK. due to their high heat losses during cold or windy weather. When the ambient temperature drops, the heat loss can easily exceed the heat gain - turning your flat plate solar collector into a radiator! The reason for the popularity of flat plate collectors is their cheap construction - you can build one yourself for a few pounds worth of scrap material, or you can buy one for £300-500. This is typically a lot cheaper than evacuated tube panels.......until now! Don't fit a dinosaur! Vacuum tube collectors will provide useful heat for 12months of the year, as long as there is daylight, and can even produce heat in overcast weather. (In April, on an overcast day without any sunshine it is still able to heat a 210litre hot water cylinder to 40°C) So if your going to fit a Solar System to your house FIT THE BEST..
A Word on Plastic Pipework There are some flat plate systems for sale in the UK, such as the Solar Twin system, which use plastic, silicone or rubber pipework, which makes installations easier and to reduce costs. Whereas this pipework may be ideal for flat plates, it is definitely not adequate for evacuated tubes. On a hot sunny day, flat plates may heat water up to a temperature of 60°C. Evacuated tube systems are capable of heating the water beyond 140°C. Most plastic pipework has a working temperature of no more than 65°C, and is able to stand no more than 90°C - so we always use copper for solar installations.
Services we offer include:
* Consultation and assessment * Supply and installation * Grant application assistance * Service and Maintenance
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