Which statement best describes the difference between passive and active solar energy?

Which statement best describes the difference between passive and active solar energy?

• A. Passive uses natural heating; active uses devices like photovoltaic cells.
• B. Passive uses fossil fuels; active uses nuclear.
• C. Passive uses moving parts; active has none.
• D. Passive generates electricity; active generates heat.

Answer: (A)

The difference centers on how solar energy is captured and used. Passive solar relies on the building’s design and materials to collect, store, and distribute heat with little or no mechanical help—think large south-facing windows, floors or walls that store heat (thermal mass), and shading to control temperature. Active solar, by contrast, uses devices to collect and convert sunlight, often with pumps or fans—such as photovoltaic cells that turn light directly into electricity, or solar thermal collectors that heat a fluid pumped through a system. So describing passive as natural heating and active as using devices like photovoltaic cells captures the essential distinction.

The difference centers on how solar energy is captured and used. Passive solar relies on the building’s design and materials to collect, store, and distribute heat with little or no mechanical help—think large south-facing windows, floors or walls that store heat (thermal mass), and shading to control temperature. Active solar, by contrast, uses devices to collect and convert sunlight, often with pumps or fans—such as photovoltaic cells that turn light directly into electricity, or solar thermal collectors that heat a fluid pumped through a system. So describing passive as natural heating and active as using devices like photovoltaic cells captures the essential distinction.