Rainwater harvesting is primarily used for what purpose?

Rainwater harvesting is primarily used to collect rainwater for irrigation or non-potable uses. This practice involves capturing and storing rainwater from surfaces like rooftops and other catchments, which can then be utilized in various ways. For instance, the collected rainwater can be used for watering gardens, maintaining landscapes, and even for non-potable household uses such as flushing toilets or washing clothes. This approach not only helps in conserving water resources but also reduces the demand on municipal water supply systems.

The other options do not align with the primary purpose of rainwater harvesting. Generating electricity typically refers to other renewable energy methods such as solar or wind. Cooling buildings is achieved through HVAC systems and other cooling technologies rather than rainwater harvesting. Heating swimming pools usually involves direct heating systems, which do not directly benefit from rainwater collection. Thus, the choice highlighting irrigation or non-potable uses correctly identifies the main purpose of rainwater harvesting.