For Domestic Solar Water Heaters/Solar Geysers for Homes.   Help NRG answer what Capacity you need, by answering these questions :   a) Number of persons in your home :        b) Number of Bathrooms used regularly :      Based on your input, NRG recommends a LPD system for you.  For Industrial Solar Water Heaters/ Solar Geysers. You are looking for a Solar Hot water system for which of the following? *  Guest Houses :   Number of Bathrooms :                             Based on your input, NRG recommends a LPD Solar Water Heater system for you. *  3 Star Hotels :   Number of Bathrooms :                             Based on your input, NRG recommends a LPD Solar Water Heater system for you. *  5 Star Hotels :   Number of Bathrooms :                             Based on your input, NRG recommends a LPD Solar Water Heater system for you.