Capturing heat from solar energy to preheat water for sanitising the milk harvesting plant can save electricity and energy emissions. Two common solar hot water systems are flat plate and evacuated tubes.
The systems have two main parts; the collector and a form of storage. The collectors transfer heat from sunlight to radiant energy to heat the water.
The collectors are glass covered boxes containing copper tubes which are exposed to the sun. They can either be a flat panel collector style or an evacuated tube solar collector.
• Flat panel systems: can be more sensitive to frost and are generally heavier and larger than evacuated tube systems.
• Evacuated tube systems: are generally more expensive than an equivalent flat plate system however the evacuated tube system can heat water to higher temperatures.