How Does Solar Thermal Work?
Solar Thermal is a well established renewable energy system and is made up of solar collectors (panels), a pump station, a solar controller and a twin coil cylinder. The solar collectors capture heat generated from natural sunlight and transfers it into a heat absorbent fluid which is circulated onwards transferring its heat for use in hot water systems.
1. Solar Panels are located on the roof of the property which collects solar radiation, heating the solar fluid contained inside.
2. When the fluid has reached the desired temperature, the pump station will begin to circulate the hot fluid down into the twin coil cylinder.
3. The hot fluid then enters the twin coil cylinder via the bottom of the coil and heats the water held inside. A sensor within the cylinder monitors the temperature of the water as it increases. The hot water is then ready for use within the home.
4. If the water within the cylinder doesn't reach 60C, or the set temperature, the boiler will fire up to supplement the system.
Solar Collectors
Solar Collectors (panels) which are generally located on the roof of a property are designed to trap solar radiation, heating the solar fluid contained inside.
Solar Collectors consist of a matrix made up of narrow gauge copper tubes, each containing absorber system fluid. Each tube is ultrasonically welded to an absorber plate that's coated to enhance energy absorption. The matrix is sealed into an aluminium casing with the front covered with a self-cleaning tempered glass, providing maximum energy penetration and robust design.
There are two main types of collectors (panels) which can be utilised either Flat Plate or Evacuated Tubes. Both have their own merits, Flat Plate collectors are constructed of minimal components and are viewed by many as more aesthetically pleasing, or Evacuated Tubes which utilise heat pipe technology to transfer the heat, these are a little more expensive but slightly more efficient.
Solar Pump Station
The pump station consists of a variable speed pump together with a flow meter to set the system flow rate. It works by pumping the absorber fluid from the solar collectors into the twin coil cylinder.
The solar pump station features a pressure relief valve, gauge and a flow and return thermometers for ease of use and control.
Due to its small size, the pump station can be installed out of site for minimum disruption, for example this part of the installation is placed within a cupboard or in the loft space of a property.
Solar Controller & Twin Coil Cylinder
The solar controller provides the temperature selection settings for the cylinder, using two temperature sensors it determines when the pump is run in order to gain solar energy from the collectors.
A hot water cylinder with two coils should be used in an efficient solar thermal system. The lower coil connects to the solar circuit, whilst the upper coil connects to the normal boiler.
The cylinder capacity can be determined from the size of the household or commercial premises and the number of solar collectors.
