Utilizing a Small Solar Water Heater for Sustainable Tea and Coffee Preparation

Tea and coffee are the most common drinks both in urban as well as rural areas. Mostly LPG, wood or kerosene are used for preparation of tea in rural and urban areas. Use of fossil fuels is polluting, and adds to the cost. It is felt that small size solar thermal water heaters can help in partial saving of the conventional fuels. Therefore, in the present work the design and study of a low-cost small size solar water heater used as tea/coffee making system is described. The work suggests the installation of low-cost water heating system with the tea stall to reduce the consumption of fossil fuels and generate energy savings. The works presents the design, experimental work and the economic analysis of the system with reporting of the payback periods. The experimental study of a solar tea/coffee maker with evacuated tubes is presented here. The system can be used for a number of short services (20 cups) and with total of 200-300 cups/day. The advantage of this system is that it is very low cost and has minimum components. The experimental thermal performance of the system is also found to be quite good. Maximum temperature observed with these tubes was around 107oC in winter. Several experiments were performed with solar system to prepare tea including black tea, green tea and tea with milk. The taste of the tea samples prepared was found to be good. In this paper the energy savings for different type of fuels are calculated and the payback periods are reported. The payback periods are found to be in the range 1.7 to 3.8 years with respect to different fuels. This study shows that small size solar water heater based on evacuated tubes can help in substantial energy savings for tea/coffee making stalls.