What Are the Different Types of Solar Energy Equipment?

A solar collector is a device that converts the radiant energy of the sun into thermal energy. Because solar energy is more dispersed, it must be managed to concentrate it, so the collector is a key part of various solar energy installations. Due to different uses, collectors and their matching system types are divided into many types and have different names, such as solar stoves for cooking, solar water heaters for generating hot water, solar dryers for drying items, and Solar furnaces for melting metals, as well as solar houses, solar thermal power stations, solar desalination plants, etc.

Solar collectors

A solar collector is a device that converts the radiant energy of the sun into thermal energy. Because solar energy is more dispersed, it must be managed to concentrate it, so the collector is a key part of various solar energy installations. Due to different uses, collectors and their matching system types are divided into many types and have different names, such as solar stoves for cooking, hot water heaters

Name: Solar energy-collector

Subject Keywords or Keywords: Solar Energy Science

A solar collector is defined as a device that absorbs solar radiation and transfers the generated thermal energy to a heat transfer medium. This short definition contains a wealth of meanings: first: the solar collector is a device; second: the solar collector can absorb solar radiation; third: the solar collector can generate thermal energy; fourth : Solar collectors can transfer thermal energy to a heat transfer medium.

Although solar collectors are not end products directly facing consumers, solar collectors constitute various solar heat utilization systems.

Classification of solar collectors

1. According to the type of heat transfer medium of the collector: liquid collector, air collector

2. According to whether the solar radiation entering the lighting port changes direction: light-concentrating collector, non-light-concentrating collector

3. According to whether the collector is tracking the sun, it is divided into: tracking collector, non-tracking collector

4. According to whether there is a vacuum space in the collector, it is divided into: flat-type collector,

The flat-plate solar collector is mainly composed of a heat-absorbing plate, a transparent cover plate, a heat-insulating layer and a shell. A water heater composed of a flat-plate solar collector

In order to improve the efficiency of solar collectors, the only effective way is to minimize the convection and radiant heat loss while maintaining maximum solar energy collection. The use of high-quality selective absorption coating materials and high transmittance cover materials is an important way to meet the above requirements [7].

With the development of solar thermal utilization technology, the research work on selective absorbing materials in China has a history of twenty years. The development of solar collectors is also the development of coating technology. During the period, it has undergone successive generations of upgrading from non-selective ordinary black paint to selective lead sulfide and metal oxide coatings, from black nickel and black chromium to aluminum anodized coating. With the continuous improvement of coating technology, coating performance has been greatly improved. At present, the absorption surface of flat-plate collectors in China mainly adopts anodized coloring on aluminum strips and black chromium selective coating on copper strips.

The coating production technology of intermittent magnetron sputtering selective absorption coating for aluminum-nitrogen-aluminum materials has been developed with the production of vacuum tube collectors, which basically represents the current production level of selective absorption materials at low and medium temperatures in China. . Due to the poor weatherability of the coating, it is not suitable for the use of flat plate collectors.

At present, the production of selective absorption coatings in developed countries in the world, especially in Europe, has two main characteristics. One is the use of

There are some misunderstandings in the industry regarding flat collector solar systems. One is the problem that the flat-plate collector solar system operates in all seasons. Many people think that the flat-plate collector solar system cannot be operated in winter. In fact, this view is wrong. At present, flat-plate collector solar systems generally use the recirculation and evacuation technology and secondary circulation technology (through antifreeze heat transfer), which can easily solve the problem of winterization and antifreeze of collectors in northern regions, without the worries of collectors freezing. And it can solve the problem of overheating of the system in summer (or when the hot water load is not matched), which is very beneficial to the solar heating system. In addition, the anti-overheating and anti-freezing technical solutions of reflux and emptying are also widely used in European countries such as the Netherlands, which is a very mature technical solution [9].

Another misunderstanding is the heat problem of flat collectors. Many people think that flat collectors

In view of the gap between domestic flat plate collectors and foreign technologies and quality, the following measures should be taken to improve the performance and quality of flat plate collectors:

1) Research and develop a selective coating suitable for flat-plate solar collectors. The coating should have high absorptivity, low infrared emissivity, excellent heat, humidity, and weather resistance and suitable properties.

1) The flat plate collector is simple in structure, reliable in operation and suitable in cost. It also has the characteristics of strong pressure bearing capacity and large heat absorption area, which is most conducive to the integration of solar energy systems and buildings;

2) Adopt reflux technology, flat collector solar system can easily solve the technical difficulties such as anti-freezing and anti-overheating;

3) Compared with the vacuum tube solar system, the high-efficiency flat-plate collector solar system can provide more domestic hot water under the same area;

The vacuum tube collector is a solar collector that evacuates the space between the heat absorber and the transparent cover layer into a vacuum. A water heater composed of vacuum tube collector components is a vacuum tube water heater.

Vacuum tubes can be divided into two types according to the type of heat sink material: one is a glass heat sink vacuum tube (or all-glass vacuum tube), and the other is a metal heat sink vacuum tube (or glass-metal vacuum tube). Heat pipe type vacuum tube is a kind of metal heat sink vacuum tube. It consists of heat pipe, heat sink, glass tube and metal end cap.

Ceramic solar collectors are mainly composed of ceramic solar panels, transparent cover plates, thermal insulation layers and shells. A ceramic solar water heater is a water heater composed of a ceramic solar collector.

When the ceramic solar collector works, the solar radiation passes through the transparent cover and is projected on the ceramic solar panel, absorbed by the ceramic solar panel and converted into thermal energy, and then transferred to the heat transfer working medium in the heat absorption panel, so that The temperature of the hot working medium rises as a useful energy output for the collector. Ceramic solar panels are hollow thin-walled flat-box solar collectors with ordinary ceramics as the matrix and three-dimensional meshed vanadium-titanium black porcelain as the surface layer. Its overall is a porcelain material, which is impermeable to water and water, high strength, good rigidity, non-corrosive, non-aging, non-fading, non-toxic, harmless and non-radioactive. Thermal conversion efficiency.