Solar Thermal System
The Use of Solar Thermal Systems to Save Energy
Introduction
Solar energy is a leading renewable and clean power source. They are utilized in heating and lighting for domestic and industrial applications. While photovoltaic devices convert light to electricity, thermal systems use the suns heat for various appliances as well as generating electricity.
Solar Thermal Systems
Solar Thermal Systems utilize the sun directly or indirectly heat water, propel generators and turbines, dry products and perform other numerous functions. These equipments harness infrared rays that increase the temperature of the working fluids such as air, water of special liquids. The hot fluids are then transferred from the source to the destination point and used to perform a range of activities.
Solar Water Heater
Solar water heater is used to heat water in domestic, industrial and for commercial hotels. They comprise of a flat plate collectors, the piping system, storage tanks and control valves. The collectors are specially manufactured to harness and concentrate the infrared rays. The absorbed heat increases the temperature of the fluid that is then used in a variety of functions such as space heating, bathing, cleaning and cooking.
These devices can either be passive or active. The former utilizes temperature gradient to convey fluids from generation to utilization point while the later uses a pump to propel the working fluid through the system. These devices are economical and reduce carbon footprint and are increasingly be used in hotels, residential areas and for industrial processes.
Warm Water Swimming Pools
Swimming pools that are partially warmed to create comfort during swimming is known as warm water swimming pools. The pool is warmed through liquid petroleum gas, piped natural gas and solar. The different sources can be combined and used to supplement each other so that the pool remains warm irrespective of the sun availability.
Solar Thermal Power Plant
Solar thermal power plants harness heat sunlight, concentrate it and convert it to electricity. They are used at medium and large scale to generate grid power. They are used for residential, industrial and commercial areas. In the tower system, an array of flat or parabolic mirrors is used to focus heat on a tower where the fluid is heated to extremely high temperature and used to drive turbines and generators.
Parabolic reflectors system uses parabolic mirrors to concentrate infrared rays to a small section so that the working fluid is heated to very high temperature. This hot liquid is then expanded in a turbine that is coupled to a generator.
Sun Drying Processes
Sunlight has been used from time memorial to dehydrate seeds and other systems. In the direct system, the seed or the substance to be dried is directly exposed to the sunlight. In the indirect system, the sun warms the air which is then conveyed to the drying compartment. This system can be used to dry seeds, clothes, utensils and in numerous industrial applications.
Power Equipments
Various power equipments are used in thermal and photovoltaic modules. These include: charge controllers, modules, tracking devices, batteries, collector tanks, pipes, plumbing tools, sensors, thermostats and concentrators.