How does a Alpha KT Solar evacuated tube system work?
Modern solar design uses tubes that consist of 2 layers of borosilicate glass with a vacuum layer between them. The vacuum acts like a thermos flask, retaining up to 97% of the thermal energy, resulting in an increased efficiency. The Sun's thermal energy is then transferred to the manifold via the U pipes located in each tube.
The Alpha KT solar evacuated tube collector delivers a measurably higher performance than other evacuated tube or flat plate systems on the market today. Alpha KT Solar evacuated tubes contain not one but two transfer pipes to double the heating capacity of each tube. This is called the U pipe system and when combined with Alpha KT Solar’s unique CPC reflector, creates a smaller high performance collector that outperforms all equivalent heat pipe and flat plate systems.
The unique CPC or Compound Parabolic Concentrator reflector ensures that the sun’s rays can reach all 360˚ of each tube’s surface area. Even on a dull winter day your Alpha KT Solar collector will be working hard, saving you money.
What does the CPC reflector do?
The unique CPC reflector is a highly polished metal component that sits just below each tube in the collector. It ensures that the sun’s rays are reflected from the highly polished surface right into the back surfaces of the tubes to ensure the most efficient capture of the available light.
Will my Alpha Energy System work if the sun doesn’t shine?
Yes. As long as there is light on rainy or cloudy days the super efficient U pipe and CPC reflector should ensure that you achieve some solar gain. All Alpha Energy hot water systems also have electric or gas boost available for water heating when there is insufficient light.
Does my Alpha Energy system qualify for Government rebate or subsidy?
All Subsidies have been canceled since July 14th 2012
Does my roof collector need to face North?
Research has proven that the most effective position for collectors is facing due North while up to 45 degrees North West or North East is acceptable with minimal effect due to the unique CPC Reflector. Also, the unique CPC Reflector means that the Alpha Energy system can be installed at almost any angle from minimum15 degrees to almost vertical.
What about frosts and freezing?
Alpha KT and the Alpha HP evacuated tubes have passed the AS/NZ 2712-2007 Standards Freeze Test to –15° C without the need for a heat exchanger or Glycol. The Alpha KT also meets AS/NZ 2712-2007 Standards for Hail resistance and does not require a guard.
Will an Alpha Energy system fit onto my existing hot water system?
Yes, a Alpha Energy system will fit onto most existing hot water systems. We recommend that you call our helpline on 07 571 2493 or contact your local distributor for help with this.
Will my collector lay flat on the roof?
Yes, due to the CPC reflector technology the Alpha KT Solar collector can be fixed flat to your roof if it is between 15° and 50°. Using a Alpha KT Solar system ensures that you only have a small discreet collector attached to your roof. For roofs below 15°, adjustable roof brackets are available to ensure that your Alpha KT Solar collector sits at the optimum angle to the Sun.The Alpha HP however should be installed at an inclination of minimum 24 degrees
Do all solar water collectors offer the same output?
NO is the answer in short...., a well designed european evacuated tube system will always offer more output over the course of a full year because it is designed to operate in european type wintery conditions therefore also excells in summer.
Flat plate panels have a high energy yield in the summer but rate poorly generally in the winter due to the panel glazing cooling amongst other things , the eveacuted tube is like a thermos flask as an example for you think of your cup of tea and how it stays hot all day in your thermos...this is because of the vacuum created between the 2 layers of your thermos flask , same principle applies to evacuated tube solar collectors
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. Providing more than this is unadvisable, as too much heat will be produced in the summer. The hot water system system can easily be automated so hot water is guaranteed regardless of sunlight levels.
How long will it take to recoup my investment?
Alpha HP solar collectors are much more affordable than many other solar hot water heaters. For a household of 4, the price of a full system may not be too much more than a new electric or gas system. 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 45% 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.
Can Alpha HP solar collectors be used in cold conditions?
Yes. Alpha HP collectors can be used in temperatures as low as -30oC, although performance is greatly reduced in such extreme conditions. Good heat output is still achieved in mild sub-zero conditions.
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 your local Alpha HP distributor. The Alpha HP solar collectors can operate with several broken tubes, but the efficiency will be reduced, so it is recommended that broken tubes be replaced immediately.
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 may be required to maintain water at the required temperature. This system will be automated so you don't have to worry about running out of hot water on a rainy day.
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.
Are the solar collectors noticeable on the roof?
If only the collector is mounted on the roof it should blend into the roof design quite well. Alpha HP 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.
Can Alpha HP 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 24o angle to ensure optimal heat pipe operation.
How do I protect my solar system during subzero temperatures?
If you have a system that is operating in areas with subzero temperatures then freeze protection must be implemented. The easiest means of preventing freezing is to use a controller with a low temperatures setting, so when the manifold temperature drops below a certain pre-set temperature (5oC/40oF), the pump will circulate, warming the collector with water from the bottom of the storage tank. The pump will not run continually, just periodically, the frequency of which will depend on the outside temperature. In extremely cold areas, a closed loop using a glycol/water mix may be appropriate.
Will the Alpha HP solar collector be a fire hazard during hot, dry weather?
No. The Alpha HP 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. The manifold outlet should be fitted with a temperature relief valve, which will prevent the manifold temperature from exceeding 99oC / 212oF.
Can the Alpha HP solar collector heat water to a high enough temperature?
Yes, in good weather the Alpha HP solar collector can bring water to boiling point. Generally this is not necessary and so the system should be designed to provide a daily temperature rise of around 25-30oC (45-54oF) in the summer. Sizing a domestic system that can bring the cold water up to 60oC/141oF in a single day is not logical, because if hot water is not used for one day, the following day the system will be boiling and dumping hot water via the temperature relief valve. This is both a waste of energy and water! Please sensibly size solar water heating system to ensure optimal performance and minimal wastage of water.
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 even be broken it should be replaced. This, however, is an inexpensive and easy job. Any "handy" person can install a new tube (while adhering to local health and safety regulations). Alpha HP solar collectors can operate with several broken tubes, however the efficiency will be reduced slightly.
Can Alpha HP solar collectors be used for a large scale hot water production?
Yes. Alpha HP 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), otherwise the water may boil.
Can I heat my swimming pool or spa using an Alpha HP solar collector?
Alpha HP 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, Alpha HP collectors may be an extremely viable supplement to gas or electricity.
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, in fact flat plate may actually be higher, but this is during minimal heat loss conditions. When averaged over a year evacuated tube collector have a clear advantage.
The key points are:
Which collector is the best value for money?
Rather than looking at just peak efficiency levels when comparing solar collectors, cost per unit of energy produced is much more logical. For example: Although collector A may be 20% more efficient than collector B, if collector A is 30% more expensive, then in fact collector B may be a better choice, as per kWh of energy produced per day it is cheaper. When payback time is of concern, not only price per kWh of the product is important, but also of the end system. In this regard Alpha HP solar collectors provides a fruther dvantage as Alpha HP solar collectors are very easy to install, and that can make a huge difference in terms of total install costs.
How do I calculate what size collector I require?
Call or email Alpha Energy
Where can I purchase an Alpha HP solar collector?
Alpha HP solar collector are available through an official distribution network.
Email us or ring Tony on +64 7 570 0092