Broan. Cooling the attic without a wire in sight, the Solar-Powered Attic Ventilator differs from standard ventilators by removing moisture from the air before the attic gets hot, rather than via temperature-triggered activation. The whisper-quiet DC motor ventilates up to 1,600 square feet and can harness solar power even in low light, the company says. Available in black, brown, or weathered wood, the ventilator fits existing attic fan holes, retrofitting in minutes, and can be surface, remote, curb, or gable mounted. 800.558.1711. www.broan.com.