Which collector type is typically used for residential solar thermal heating?

• A. Flat-plate collectors.
• B. Evacuated tube collectors are always used.
• C. Parabolic dish collectors are standard in homes.
• D. Concentrated solar collectors without tracking.

Answer: (A)

Flat-plate collectors fit residential solar thermal heating because they provide reliable, moderate-temperature heat with a simple, durable design that doesn’t require tracking. They use a dark absorber plate heated by the sun, a glass cover, and insulation to trap heat, making them cost-effective and easy to install on rooftops for hot water and space heating. While evacuated-tube collectors can offer higher efficiency in cold or diffuse conditions, they cost more and are not the default for most homes. Parabolic dish and other concentrated collectors deliver much higher temperatures and need tracking, which adds cost and complexity not needed for typical residential heating. Concentrated collectors without tracking would miss a large part of the sun’s energy as the day goes on, so they’re not practical for normal home use.