The effective solar water heaters are popular as they assist the natural sunlight to the heat the water available. The basic principle behind the system and its working is the thermosiphon principle and is designed significantly to provide hot water without any consumption of the expensive electricity. This system ensures saving of costly electric power and is also environment-friendly. Thereby, contributes to sustainable development. The choice to use a solar water heater is considered as a superior choice and its configuration and functioning ensure years of quality usage. The process is quite economical and enables substantial energy-saving strategy as solar energy is a natural and renewable source of power. Moreover, it is efficient as it is a way to produce hot water for sanitary use all the year-long without any emission of harmful greenhouse gases.
Structural Details of Solar Water Heater
The structure is simple and can be easily understood as the first part consists of the heat collecting component. The heat acquiring element works as the main part of the system. The radiation energy is used which is known as irradiance. The outer wall of the inner tube is coated with a selective absorbing coating which then used in the water heaters. Solar panel collector plate coated with black chromium absorbing film, and the heat collecting plate is welded by metal tube are the other parts present in its structural details. The flat plate collector is increased in trend in the present market as it helps in developing high-rise residential balcony type solar energy water heater.
The thermal insulation water tank is a container used for hot water storage. The capacity of the heater to hold a large quantity of aware varies in a wide range according to the place it has to be used. The liner, insulation layer and the tank shell are present in thermal-based solar water heaters. The material strength and corrosion resistance are the defining factors of the quality of the product. The quality of insulation layer materials is directly dependent on the insulation effect. The steel plate, galvanized plate or stainless plate is usually used for the material of the shell.
The best working condition with high stability and perfect design of the heater's integral system is possible with the assistance of connected pipes as solar pipes ensure better connectivity. The durability and reliability of the system are dependent on the use of better quality raw materials. The main purpose of the connecting pipes is to transfer cold water to the hot water storage tank after the heating process. The Controllers are used to control the water movement with the anti-dry burning function. They allow the whole system to function at a particular temperature with stable and well-founded outcomes.
The technology used is explainable and conceptual idea is brilliant behind the logical functioning of the solar power water heater. Sunlight strikes the absorber surface of the collector. These roof-mounted solar heaters supply about 85 percent of the hot water for the home through a well-maintained heater every day. The actual potable water to be used flows through pipes like tubes attached to the absorber and takes the heat from it. The exchanger can also be used for a similar purpose. The heated water is then stored in a separate tank. The proposed system is generally installed on the rooftop, open ground, with the a continuous water supply and the sun-facing system.
Types of Solar Water Heaters
There are various types of solar water heater:
- Thermosiphon System: The water movement, and heat transfer, increases with temperature, these systems are prominently used in areas with high temperature and irradiance. It is considered as a general well-structured type of solar heater
- Direct-Circulation System: The system pump water from storage to collectors during sunny hours. Freeze protection is obtained by recirculating hot water of the warm storage tank. These are used in the areas of varying freezing rates. High maintenance is required for this system.
- Drain-Down System: In this system, the treated is circulated through a closed-loop, and heat is transferred to the available water through a heat exchanger. When no solar energy is present, the collector fluid is transferred to the ground storage chamber by gravity to avoid freezing. The system is based on a well-planned structure for every season.
- Indirect Water-Heating Solar System: The freeze-protected fluid is circulated through a closed-loop and its heat is transferred to the water through a heat exchanger. The water-ethylene glycol solutions and water-propylene glycol solutions for efficient protection from the freezing of water. The system has a maximum efficiency of about 85 to 90 percent and generally used in cold regions of the globe.
The government subsidiaries are beneficial in reducing the cost of the heater for the customers. It encourages people to use zero pollution-based heaters. About 30 percent of the subsidiary is provided by the government generally in this case but it varies from state to state in India. The scheme provides 60%subsidy profits on special category states like the North-East states, Hilly area states, and islands. Special category states for domestic installations 60% capital subsidy or loan at 5% interest on 80% of the benchmark cost has been provided while for the commercial purposes the 30% capital subsidy or loan at 5% interest on 80% of the benchmark cost.
Things to remember while choosing a brand
A quality assurance, regular reviews, monthly quality check of different regional brands and performance-rating program for solar heaters must be conducted to make it easier to select reliable equipment with confidence. The standards must be maintained and verified for all the areas including the areas of poor water quality i.e. salty and hard water. The number of products of different brands are available today. So, to select best product for your space following points must be kept in mind like water source, purpose of the heater at home, type tank used, service life, the water pressure system, the reviews by the current customers of the selected brand, quality standards provides with the temperature regulation scheme, professional installation with climatic conditions and maintenance requirements.