| Abstract [eng] |
This work evaluates various solar energy conversion technologies for industrial technological process heat generation. Solar energy is most applicable for processes, which require temperatures of up to 100 °C. Such temperatures are found in 13 % of industrial technological processes. At these temperatures the most commonly used collectors are flat plate (P) and evacuated tube (V) collectors. Also, hybrid modules (PVT) could be used, which carry out cogeneration, i. e. simultaneous heat and energy generation. Using the program Polysun simulations were done for possible solar energy systems. The simulation object was selected according to the industrial sectors, which are the most relevant for solar energy usage. It was found that wood, food and textile manufacturing sectors are the most relevant ones. According to these industrial sectors, a milk processing plant with an industrial profile, 80 m3 volume and 80 °C temperature hot water daily load was selected as the simulation object. During the course of the simulation different solar energy conversion technologies (P, V, PVT), collector amounts (20–100) and ratios of storage tank volume to collector aperture area (50–100 l/m3) were taken into account. The simulations were done for four different system layouts: using an external heat exchanger for the solar loop (variant 1), using an internal heat exchanger for the storage tank (variant 2), using an external heat exchanger between the storage tank and the boiler, and using an internal heat exchanger for the storage tank (variant 3) and using external heat exchangers on sides of the storage tank (variant 4). In total 180 cases were simulated. For each simulation cases solar fractions, generated electrical energy (PVT), net present values after 25 years and other units were founds. It was found that variant 1 (followed variants 2, 4 and 3) has the highest solar fractions: up to 6,7 % (V), 6 % (P) and 3,5 % (PVT). About half of PVT module system yearly income consists of electricity generation for self-use. After a financial analysis it was found that solar collector systems recoup after 10–21 years and PVT systems don‘t recoup within their lifetime of 25 years, if the granted subsidy is 50 %. If the subsidy would be maximal (80 %), the systems would recoup after 3–6 (V, P) and 7–10 (PVT) years. |
