The capacity of solar water heater is your most important issue. Determining the capacity of a container will depend on two factors. The first factor is the number of family members. The second factor is the need to use domestic water heaters on a regular basis.
For families with smaller members, 150 litres of water for 2 to 3 members should be used. If you need to use it frequently, you can choose the type of about 200 liters. With this container capacity, your family can use it comfortably for 3-5 days.
Most families now have between 4 and 5 members. At this time, you should choose a capacity of 200 liters solar water heater or more to meet your needs. Solar water heaters 200-250l are the type most often chosen by many people.
If there are many family members (more than 6 people) or need a lot of use. You can only choose the type of hot water tank from 300 liters to meet your needs. In short, one people needs about 50 liters, and you can according to the number of households to choose the capacity of solar water heater.