One of the latest trends when it comes to heating water in residential
spaces is based on harnessing solar energy and convert it into
electricity. In order to do this, solar water heaters are used. Such solar water heaters are designed to use sun heat in order to provide households with hot water. They include solar collectors and storage tanks.
Also, they use sun heat to heat heat-transfer fluid or water in the sun collector. Most of them require well insulated storage tanks. For instance, the solar tank can actually be a modified standard heater but usually, it is a very well insulated
and larger tank. Also, solar tanks come with additional inlet and
outlet connected from and to the collector. In the case of a two-tank
solar system,
the heater will preheat the necessary amount of water before it enters a
conventional water heater. In the case of a one-tank solar system, a
back-up water heater is combined with a solar storage in just one tank
in order to provide the necessary amount of heated water.
Solar collectors are designed to gather sun energy and transform this radiation into heat. Then, this heat is transferred to solar fluid or water. There are 3 types of solar collectors that can be used in the case of solar water heating systems. First, there are the so-called flat-plate collectors – a typical flat-plate collector is made of an insulated metal box that comes with an absorber plate and a plastic or glass cover. This cover is called the glazing. On the other hand, unglazed flat-plate collectors, typically used for residential pool heating, come with an absorber made of polymer or metal and without any enclosure or cover. Integral collector-storage systems are made of 1 or even more black tubes or tanks in insulated glazed boxes. In their case, cold water will first pass through a solar collector that will preheat it and then the water continues to a conventional back-up water heater.
Evacuated-tube solar collectors are designed to achieve very high temperatures of up to 350°F and this is the main reason why they are more appropriate when it comes to cooling industrial and commercial applications. Such collectors are made of some parallel rows of glass tubes – each of these tubes contains a metal absorber tube and a glass outer tube attached to a fin. This fin is covered with an absorbing coating designed to absorb solar energy and inhibit the possible heat loss. In their case, air is evacuated or removed in order to eliminate convective and conductive heat loss. Solar water heaters can be active or passive. The active ones are designed to use pumps in order to make pressurized potable water circulate directly through the solar collectors or pumps that circulate heat-transfer fluids through these solar collectors. Passive solar water heaters rely mostly on gravity and use the natural tendency of water to circulate as soon as it is heated. Passive solar water heaters can be integral or Thermosyphon ones.
Integral collector-storage passive ones consist of 1 or more storage tanks that are placed in insulated boxes with the glazed sides facing the sun while Thermosyphon systems rely mostly on the natural convection process of water meaning its tendency to circulate through the tank and collectors once it’s heated. As water is heated in the solar collector, it becomes much lighter and starts rising naturally right into the solar tank above. Meanwhile, the amount of cooler water will flow down the solar pipes right to the bottom of a collector thus enhancing the circulation. When using solar water heating systems, back-up systems are necessary in order to face times of increased demand or cloudy days. For instance, you can go for a conventional storage water heater that can provide the necessary backup and that can also become an integral part of your solar system package.
Solar collectors are designed to gather sun energy and transform this radiation into heat. Then, this heat is transferred to solar fluid or water. There are 3 types of solar collectors that can be used in the case of solar water heating systems. First, there are the so-called flat-plate collectors – a typical flat-plate collector is made of an insulated metal box that comes with an absorber plate and a plastic or glass cover. This cover is called the glazing. On the other hand, unglazed flat-plate collectors, typically used for residential pool heating, come with an absorber made of polymer or metal and without any enclosure or cover. Integral collector-storage systems are made of 1 or even more black tubes or tanks in insulated glazed boxes. In their case, cold water will first pass through a solar collector that will preheat it and then the water continues to a conventional back-up water heater.
Evacuated-tube solar collectors are designed to achieve very high temperatures of up to 350°F and this is the main reason why they are more appropriate when it comes to cooling industrial and commercial applications. Such collectors are made of some parallel rows of glass tubes – each of these tubes contains a metal absorber tube and a glass outer tube attached to a fin. This fin is covered with an absorbing coating designed to absorb solar energy and inhibit the possible heat loss. In their case, air is evacuated or removed in order to eliminate convective and conductive heat loss. Solar water heaters can be active or passive. The active ones are designed to use pumps in order to make pressurized potable water circulate directly through the solar collectors or pumps that circulate heat-transfer fluids through these solar collectors. Passive solar water heaters rely mostly on gravity and use the natural tendency of water to circulate as soon as it is heated. Passive solar water heaters can be integral or Thermosyphon ones.
Integral collector-storage passive ones consist of 1 or more storage tanks that are placed in insulated boxes with the glazed sides facing the sun while Thermosyphon systems rely mostly on the natural convection process of water meaning its tendency to circulate through the tank and collectors once it’s heated. As water is heated in the solar collector, it becomes much lighter and starts rising naturally right into the solar tank above. Meanwhile, the amount of cooler water will flow down the solar pipes right to the bottom of a collector thus enhancing the circulation. When using solar water heating systems, back-up systems are necessary in order to face times of increased demand or cloudy days. For instance, you can go for a conventional storage water heater that can provide the necessary backup and that can also become an integral part of your solar system package.
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