Determining the size of an off-grid solar system is straightforward: it’s based on average consumption. A good rule of thumb is that a system should generate 10kWh per day for one person, with an additional 5kWh per day for each additional person. For a three-person household, this would total 20kWh. Following another rule of thumb, dividing this total by 2 suggests a solar system size of around 10kW to meet the household’s needs. As a result, for off-grid solar systems, the starting point is a 5kW setup for a single individual, with an increment of 2.5kW for every additional person in the household. This approach provides a more precise framework for determining the necessary system size based on the number of occupants.