1. Is solar water heating a viable alternative to gas or electricity?
2. How long will it take to recoup my investment?
3. Can Apricus solar collectors be used in cold conditions?
4. What happens if one of the tubes is broken?
5. Will water be heated on a cloudy day?
6. Can I use a solar collector with my existing hot water system?
7. Are the solar collectors noticeable on the roof?
8. Can Apricus solar collector be mounted on a flat surface?
9. How do I protect my solar system during subzero temperatures?
10. Will the solar collector be a fire hazard during hot, dry weather?
11. What maintenance of the solar collectors is required?
12. Can Apricus solar collectors be used for a large scale hot water production?
13. Can I heat my swimming pool using an Apricus solar collector?
14. Are solar tube collectors more efficient than flat plate collectors?
1. Is solar water heating a viable alternative to gas or electricity?
Solar should not be seen as a alternative to gas or electricity, but rather a supplement. Solar cannot totally replace the need for gas or electric heating as there are sometimes days when there is little sunlight. When averaged over a year, a correctly sized solar system can provide 60-70% of a household's hot water needs.
2. How long will it take to recoup my investment?
As soon as it's installed, you start saving on your monthly energy bills.
Apricus solar collectors are much more affordable than many other solar hot water heaters. Depending on you location (solar levels) and current hot water usage the annual electricity or gas saving will differ. However in a normal household that spends 25% of its electricity bill on hot water heating, the full cost of the purchase may be recouped as quickly as 4-5 years in reduced bills. You will definitely make considerable savings during the life of the solar hot water heater.
3. Can Apricus solar collectors be used in cold conditions?
Yes. Apricus collectors can be used in temperatures as low as -30oC, although performance is reduced in such extreme conditions. Good heat output is still achieved in mild sub-zero conditions.
4. What happens if one of the solar tubes is broken?
Firstly, tubes are very strong and not easily broken, but if the worst should happen, solar tubes can be replaced very easily. They are inexpensive and available though Solar Solutions. The Apricus solar collectors can operate with several broken tubes, but the efficiency will be reduced, so it is recommended that broken tubes be replaced immediately. Each installation is supplied with two spare tubes.
5. Will water be heated on a cloudy day?
Yes. Although the heat output of the solar collector is reduced on overcast days it will still be able to provide heating. If it is a heavily clouded day or raining, then more gas or electric boosting will be required to maintain water at the required temperature.
6. Can I use a solar collector with my existing hot water system?
Normally yes. Simple retrofit valves can often be used to allow solar to connect to your existing cold water inlet. If your tank cannot accept the solar input directly an additional storage tank can be installed to pre-heat the cold water prior to entering the existing tank or combi boiler.
7. Are the solar collectors noticeable on the roof?
It should blend into the roof design quite well. Apricus solar collectors are very thin and can be flush mounted on a roof. From a distance they look somewhat like a skylight. You may have to check with your local council regarding building restrictions when installing your solar collector.
8. Can Apricus solar collectors be mounted on a flat surface?
Yes they may be mounted on a flat roof, or on the ground by using a stainless steel Flat Roof Frame. The collector should be installed at a minimum of 20o angle to ensure optimal heat pipe operation.
9. How do I protect my solar system during subzero temperatures?
The installation has an automatic system which sensors when the temperature falls below 5°C; this operates the pump allowing warmed water from the hot water system to circulate, thus maintaining the temperature above 5°C.
10. Will the Apricus solar collector be a fire hazard during hot, dry weather?
No. The Apricus solar collector's components are all high temperature rated and non-flammable so even during strong sunlight with the circulation pump turned off (stagnation), the system will not catch alight or give off any sparks. The majority of the solar collector's components are stainless steel, aluminium, glass or glass wool.
11. What maintenance of the solar collector is required?
Under normal circumstances no maintenance of the system is required. Due to the shape of the tubes regular rainfall and wind should keep the tubes clean. Should a tube be broken it should be replaced. This is an inexpensive and easy job.
Apricus solar collectors can operate with several broken tubes, however the efficiency will be reduced.
12. Can Apricus solar collectors be used for a large scale hot water production?
Yes. Apricus solar collectors can be connected in series or parallel to provide large scale hot water production for a commercial settings such as a school, hotel or office building. There is really no limit to the size of the system, however collectors must be installed in banks of no more than 150 tubes (in series).
13. Can I heat my swimming pool or spa using an Apricus solar collector?
Apricus collectors are high temperature collectors, and are therefore ideal for spas, as the volume of water is small and temperature requirements high. For swimming pools, however, the volume of water is large and the temperature rise required is only several degrees. The cost of heating a pool using solar tube collectors (for domestic purposes) may be prohibitively high. For large scale swimming pools, however, Apricus collectors may be an extremely viable supplement to air sourced
heat pumps.
14. Are solar tube collectors more efficient than flat plate collectors?
When comparing peak efficiency levels it may seem that there is little difference between flat plate and evacuated tubes, but this is during minimal heat loss conditions (ie summer). When averaged over a year evacuated tube collectors have a clear advantage. The key points are:
 Due to the cylindrical shape of the evacuated tube, the solar tubes are able to passively track the sun throughout the day. Flat plate collector only provide peak energy output at midday when the sun is perpendicular to the collector's surface.
Air is evacuated from the solar tube to form a vacuum. This greatly reduces conductive and convective heat loss from the interior of the tube. As a result wind and cold temperatures have less effect on the efficiency of the evacuated tube collector. Apricus solar collectors can often be used in subzero temperatures without the system sustaining damage. Flat plate systems often require expensive and complicated "antifreeze" systems to be installed.
Evacuated tubes are strong, long lasting, and should one be broken, inexpensive and easy to replace. If a flat plate collector panel is damaged the whole panel must be replaced.
Due to the high efficiency absorption of solar radiation even during overcast conditions, combined with excellent insulative properties of the solar tube, collectors can heat water all year round (backup from gas and electricity is still required).
Due to the various advantages of evacuated tube collector over flat plate collectors, a smaller collector can be used to provide the same heating performance. For example, a standard household of 4-5 people would usually require a 140-210L water storage tank. Depending on your location, only 30 evacuated tubes would be required to provide all summer hot water needs and a large percentage in other seasons.
Flat plate solar collectors can produce similar heat output to evacuated tube collectors, but generally only during warm, still, sunny conditions. When averaged over an entire year, evacuated tube collector heat output per net m2 of absorber area, is between 25% to 40% greater that a flat plate collector.
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