Solar Hot Water Heating By: Ryan Kim
Contents • Introduction to Solar Heating • How Solar Hot Water Heating Works • Passive and Active Hot Water Heating • Different Designs of Solar Hot Water Heating • Conclusion • References
Introduction to Solar Heating Picture taken from: http://www.solarexpert.com/Heatdhw.html • Been around since the 1800s • Modern applications resemble skylights • Significantly reduce energy bills • Generation of energy depends on: • Geographic location • Design of system • Size and orientation of solar collector Reference: http://www.toolbase.org/techinv/techDetails.aspx?technologyID=112
How Solar Hot Water Heating Works Picture taken from: http://www.pharoengineering.com.my/DOMESTICPAGE.htm • Cold water supply connected to solar storage tank (another water tank separate from the water heater) • Water is circulated between solar storage tank and solar collectors • Heated water from the solar storage tank is outputted to input of conventional water heater • If water is not as hot as necessary, conventional water heater heats it up Reference: http://www.solarexpert.com/Heatdhw.html
Passive and Active Water Heating • Passive (Gentle Climates) • Uses a batch heater, which could be a water tank painted black • For more efficiency, tank can be insulated and glazing can be installed • Storage tank usually located on the roof • Active (Harsher Climates) • Uses a small pump for circulation since there is no tank on roof • Although it uses electricity, it generates a lot more energy • Also has valves and controllers • Easier to install References: http://www.jc-solarhomes.com/how_to.htm http://www.toolbase.org/tertiaryT.asp?DocumentID=3216&CategoryID=949
Different Designs of Solar Heating • Types of Systems • Open-Loop (Direct) Active • Circulates household water • Closed-Loop (Indirect) Active • Circulates heat-transfer fluid • Heat exchangers transfer heat from fluid to water in storage tanks • Batch Heaters (Passive) • a.k.a “Bread Box”, ICS systems • Storage tanks contained inside insulated boxes with a glazed side • Mounted on ground or roof • Thermosiphon (Passive) • Relies on natural convection • Tank mounted on top of collector • Can be a closed-loop to prevent freezing Reference: http://www.toolbase.org/tertiaryT.asp?DocumentID=3216&CategoryID=949
Conclusion • Generate at least 70% of energy required to heat water • Technology used for over a century in household heating • Several types of installations make it feasible for consumers • Therefore, solar water heating is one of the most cost-efficient and environmentally friendly solutions for hot water production in a household.
References • Canivan, John. “How to Build a Solar Hot Water System.” Accessed on October 9, 2005 http://www.jc-solarhomes.com/how_to.htm. • “Solar Water Heaters.” NAHB Research Center. Accessed on October 9, 2005 http://www.toolbase.org/techinv/techDetails.aspx?technologyID=112. • “Solar Water Heating.” NAHB Research Center. Accessed on October 9, 2005 http://www.toolbase.org/tertiaryT.asp?DocumentID=3216&CategoryID=949. • “Solar Water Heating Consumer Guide.” GO Solar Company. Accessed on October 9, 2005 http://www.solarexpert.com/Heatdhw.html.