CALCULATION OF EFFICIENCY OF FLAT SOLAR COLLECTORS

Аннотация

The article examines the energy efficiency of the solar water heating collector. The operation procedure, elements and functions of the solar water heating collector are described. The methodology and expressions for calculating the energy efficiency of the solar water heating collector have been developed. Keywords: solar water heating collector, energy efficiency, thermal energy, energy efficiency of solar collectors, solar hot water systems. Introduction. The energy efficiency of solar collectors represents the ability to convert solar energy into thermal energy. Solar collectors often convert the sun directly into thermal energy, which offers somewhat lower energy costs and environmental benefits. To calculate and evaluate the energy efficiency of solar collectors, you can perform the following steps: Solar collectors are used to heat industrial and household buildings, supply hot water for production processes and household needs. The most production processes that use hot and hot water (30÷90℃) together with domestic needs occur in the food and textile industries, so we focus on the use of solar collectors, its efficiency and resource saving. needed. The solar collector is the main element of solar hot water systems [1-5]. Solar collectors are solar energy devices designed to absorb solar radiation and convert it into thermal energy [6-9]. The efficiency of the heat and hot water supply system largely depends on the efficiency of the solar collector. All structural features of any solar collectors should allow maximum absorption of solar energy and minimum heat loss. The more the collector system absorbs solar energy, the faster it converts this radiation into heat energy, and the less heat is lost on the way to the heat accumulator and the pipe to the consumer, the more efficiently this system works [10-12]. Materials and methods. A solar water heater (SWH) is a system designed to capture solar energy and convert it into thermal energy for heating water. This renewable energy technology can significantly reduce energy bills and environmental impact compared to conventional water heating methods. Here’s 51 THEORETICAL ASPECTS IN THE FORMATION OF PEDAGOGICAL SCIENCES International scientific-online conference a comprehensive guide on how solar water heaters work, their components, benefits, and considerations. Solar water heaters use solar energy to heat water through a collector. The basic operation involves: 1. Solar Collectors: o Flat-Plate Collectors: These are commonly used in residential applications. They consist of a flat-plate absorber with a transparent cover to trap sunlight and a heat-absorbing element. o Evacuated Tube Collectors: These collectors have multiple glass tubes with a vacuum between them, which improves efficiency by reducing heat loss. 2. Heat Transfer: o Direct Circulation Systems: Water circulates directly through the collectors and into the storage tank. Suitable for areas with moderate freezing risks. o Indirect Circulation Systems: A heat-transfer fluid (like antifreeze) circulates through the collectors, transferring heat to the water in the storage tank through a heat exchanger. Ideal for areas with freezing temperatures. 3. Storage Tank: o A well-insulated tank stores the heated water, ensuring it remains hot until needed. 4. Controls and Valves: o Thermostatic Controls: Regulate water temperature and manage the operation of the system. o Check Valves: Prevent backflow of water. 5. Pumps (for active systems): o Circulation Pump: Moves water or heat-transfer fluid between the collector and the storage tank. The housing of flat solar collectors uses thermal insulation, reflective coating of glass, solid wall, which ensures a long service life. They are simply and reliably installed flat and on the roof, installed anywhere on the roof and buildings [15-19]. The efficiency of the solar collector is the ratio of useful heat energy to the incoming solar energy. In addition to thermal losses, in some cases optical losses also occur in the device. The optical efficiency determines what percentage of the radiation through the transparent coating reaches the collector and is absorbed by the absorber. 52 THEORETICAL ASPECTS IN THE FORMATION OF PEDAGOGICAL SCIENCES International scientific-online conference Results. To evaluate the efficiency and design parameters of solar collectors for a solar water heating system, we can use the given formulas. These formulas help determine the collector efficiency, required collector area, and potential fuel savings from using solar energy. Here’s a detailed explanation and calculation process for each formula: As a first approach, the efficiency of solar collectors can be calculated using the following formula [8]: k𝚫𝐓 η = η − , (1) 0 E where, η is the calculated value of FIK, %; η is the optical efficiency of the 0 device under normal conditions, %, k is a coefficient depending on the type of 1 collector and thermal insulation, ΔT is the tem