Solar energy is primarily used to perform which of the following?

Solar energy is primarily utilized to heat water or air due to its ability to capture and convert sunlight into thermal energy. This process involves using solar panels or solar thermal systems that harness sunlight, which can then be used to warm residential water supplies, pool water, or even provide heating for homes. This direct application of solar energy is common in solar water heating systems and is a fundamental aspect of renewable energy usage aimed at reducing reliance on fossil fuels for heating purposes.

The other options focus on different energy processes or fuel sources. Generating wind energy involves the use of wind turbines, mining uranium is related to extracting material for nuclear power, and producing nuclear fuel pertains to fission-based energy. None of these processes directly involve the key functionalities of harnessing solar energy, making the use of solar energy for heating water or air the most appropriate choice.