Types of Solar Water Heaters Solar water heaters can be roughly divided into the following categories:
1. From the heat collection part:
(1) Glass vacuum tube solar water. Heating: can be divided into It is divided into all-glass vacuum tube type, heat pipe vacuum tube type, U-shaped vacuum tube type/vacuum tube heat collection and heat storage drying type integrated sun. The most commonly used is the all-glass vacuum tube type, which has the advantages of safety, energy saving, environmental protection and economy. Especially solar water heaters with auxiliary electric heating function, which use solar energy as the main source and electric energy as the auxiliary energy source, so that the solar water heater can work normally all year round and the efficiency is still relatively high when the temperatureambient is low. Its disadvantages are that it is relatively large in size, the glass tube is fragile, scale is easily accumulated in the tube, and it cannot work under pressure.
(2) Flat plate solar water heater: it can be divided into tube plate type, winged tube type, snake tube type, flat box type, round tube type and heat pipe. Its advantages: good integrity, long service life, few defects, low safety risks, capable of operating under pressure, safe and reliable, large heat absorption area, easy to combine with buildings, and strong resistance to heat. dry air. Performance is also very stable. . Its disadvantage is that there is no vacuum inside the cover and its thermal insulation performance is poor. Therefore, the heat collection performance is poor when the ambient temperature is low and consumes relatively littlet a lot of energy when using a supplementary heater. Thermal efficiency is lower when the ambient temperature is low or when the leaving water temperature must be high. If damaged by freezing, the entire heat collector plate must be replaced. It is suitable for southern regions where there is no ice in winter.
(3) Ceramic hollow flat plate solar water heater: Ceramic solar panels are thin-walled hollow flat box solar collectors with ordinary ceramic as the base and black porcelain on the base. vanadium-titanium with three-dimensional mesh as surface layer. Ceramic solar panels are made of porcelain material as a whole, which is waterproof, has high strength and good rigidity, does not corrode, does not age, does not fade, is not toxic, harmless and non-radioactive. the absorption rate does notwill not attenuate and has high long-term photothermal conversion efficiency.
Tested by the National Solar Water Heater Quality Supervision and Inspection Center, the sunlight absorption rate of ceramic solar panels is 0.95 and the gain of Daily heat of concrete structure ceramic solar roof is 8.6 MJ, which is much higher than the national standard. Ceramic solar panels have low manufacturing and operating costs, do not attenuate the absorption rate of sunlight, and have the same lifespan as the building. They can be used to share the structural layer, insulating layer and waterproof layer with the original structure. is simple and the thermal insulation effect is better than the original roof. The concrete structure ceramic solar roof, sunny wall and balcony guardrail integrated into the building provide hot water, heating andair conditioning to the building and providing thermal energy to industry; , agriculture and livestock; and can be used for large-scale solar hot water production and wind power generation in deserts, seawater desalination, brackish water desalination and transformation of deserts into agricultural land .
2. Classification from structure:
(1) Compact solar water heater: the vacuum glass tube is directly inserted into the water tank, and the water in the water tank is heated . by circulating the rise in temperature of the heated water, it is the most classic solar water heater on the market.
(2) Split type water heater: The split type water heater separates the collector and the water tank, which can greatly increase the capacity of the solar water heater, does not use not the waterfall working method, and expands the scope of use.around.
3.Divided by the water tank pressure:
(1) Pressurized solar water heater: The water outlet of the solar water heater is under pressure. Typically it runs on surface water and does not necessarily use a pressurized water tank.
(2) Pressureless Solar Water Heaters: Ordinary solar water heaters are pressureless water heaters. The water tank has a pipe connected to the atmosphere, which takes advantage of the height difference between the roof and the roof. the house. The water creates pressure. Its safety, cost and service life are much greater than the pressure type.
Solar water heater is a device that converts solar energy into thermal energy, heating water from low temperature to high temperature to meet people's use of hot water in life and production. Solar water heaters are divided into vacuum tube solar water heaters and screen solar water heaters.n flat depending on their structural shapes. Evacuated tube solar water heaters are mainly used, accounting for 95% of the domestic market share. Household evacuated tube solar water heaters are composed of heat collecting tubes, water storage tanks, brackets and other related parts. The conversion of solar energy into thermal energy mainly relies on vacuum heat collecting tubes which use the principle of hot water floating. and cold water flows to cause microcirculation in the water.
How do solar water heaters work
Solar thermal storage technology is a complex technology Regardless of the technical level and investment cost, the technology of Solar thermal storage is a key aspect of solar energy. of use. Judging from existing research, research on sensible heat storage is relatively mature and has reached the level of commercial development. However, due to the low density of sensible heat storage and the large size of the heat storage device, there are certain limitations. Although heat storage by chemical reaction has many advantages, it faces difficulties such as complex chemical reaction processes, sometimes requiring catalysts, certain safety requirements, large one-time investment, and overall efficiency is still low. It is currently only at the small-scale experimental stage. and will not be used in large-scale experiments. Many issues still need to be resolved before large-scale application.
Phase change storage has attracted a lot of research because of its superiority, and its development momentum is strong. However, various problems exist in the practical application of the materialsconventional phase change materials, such as supercooling and phase separation of inorganic phase change materials and low thermal conductivity of organic phase change materials, which seriously limit the application of phase change storage technology. phase in solar thermal storage. .applications in. In addition, reducing the application cost of phase change thermal storage is also a practical problem that needs to be solved before the large-scale application of phase change storage technology in solar thermal storage. Fortunately, in recent years, with the emergence of new phase change materials such as nanocomposite phase change heat storage materials, shaped phase change materials and functional thermal fluids, the above problems should be resolved. The emergence of new materials to changet phase will certainly promote the application of phase change storage technology in solar thermal storage to a large extent.
Electric storage water heater, instantaneous water heater, solar water heater. Determine which is the most appropriate from a savings point of view. My house needs an uninterrupted hot water supply. Thank you
Diagram of working principle of solar water heater 1. Cold water enters the solar water heater through the pipe, passes through the heat collector plate,The collector panel can collect the solar energy, convert solar energy into thermal energy, then heat cold water. Since the density of cold water is higher than that of hot water, the hot water will automatically increase and then form circulating power. The water will gradually heat up on the heat collecting plate. After reaching a certain temperatureture, she can enter. the hot water tank. Those who need hot water will be able to get hot water at any time. Heating Figure 2. In fact, the principle of solar water heaters mainly includes the following two principles: (1) The principle of water circulation, that is, the water flows automatically. This is based on the fact that cold water is denser than hot water. Cold water flows and hot water rises, forming natural convection that gradually heats the water in the water tank until it reaches the set water temperature. When the intensity of the sun is not sufficient to meet circulation needs, a water pump can be added to the closed water circulation circuit to obtain forced circulation. (2) Collector heat absorption principle: There is a special coating on the collector surface of the solar water heater. This coating has a high absorption rate ins the visible range of solar energy. After absorbing it in the form of heat, heat. the radiation from the collector will have the wavelength in the longwave range and the coating has low longwave emissivity, thus effectively retaining solar heat. This heat is then used to gradually heat the cold water into hot water. Solar collector tube Let's talk in detail about the collector tube on this collector. The collector tube is actually like an elongated hot water kettle liner. It is made of two glass tubes, one large and one small. the inner layer is covered with a spectrum-selective absorption coating, and a straight void is drawn between the inner and outer tubes. It forms the core of the solar water heater and is used to maximize the absorption of thermal energy after solar radiation. The vacuum glass tube is round, has the characteristics of naturally following the widesun source, coupled with the reflection principle of the reflector, the glass tube can receive light from all sides, the heat collection effect lasts longer, the water temperature is higher. , and it can work normally all year round, even in alpine areas.
The saving, of course, lies in the solar water heater, but it depends on the weather, and the uninterrupted supply of hot water depends on the scorching sun.
Installing water heaters can provide continuous hot water, but they have relatively high demands on the electricity network and are very powerful. Small power water heaters make no sense.
Electric volume water heaters are relatively large, so those who require an uninterrupted supply of hot water should choose a larger capacity.
There are two concepts of saving, one is saving electricity and the other is saving money.gent. Larger capacity volumetric electric water heaters can be used for day and night heating and can be used. all day, saving money but no electricity.
There is no energy saving in electric water heaters. The efficiency of electric heating is the same, both volumetric and instantaneous.