We wanted our new home to be as efficient as possible. We were fortunate, the builder we selected used energy-efficient materials and methods as part of their normal processes. To extend what they were doing during construction, we applied mastic to seal the duct-to-vent connections, upgraded to 16 SEER heat pumps with variable speed air handlers, and selected extremely light colored roof shingles to reflect light and heat.
Still, we knew it would be costly to operate a large two story home where air conditioning is an indisputable need. So after construction, we added ceiling fans to many of the rooms, tinted the windows to block ~50% of radiant energy, installed frame-mounted plantation shutters to block as much light and heat as possible, replaced nearly all of the incandescent light bulbs with CFLs (Compact Florescent Lighting), and jumped in to solar energy with both feet.
Our solar installation consists of four discrete technologies. We installed twenty-two photovoltaic (PV) panels on the south roof to capture the sun's energy, rated at a maximum output of 4.928 kilowatt hours. The grid-tied inverter converts the PV energy into electricity. This electricity augments Tampa Electric (TECO)'s feed from the street and also charges our battery back-up system. The eight lead acid batteries in a cabinet provide UPS-like back-up electricity to our critical load items such as the refrigerator, the microwave, telecommunications equipment, and the solar hot water heater. The solar hot water heater works by sending water to a 4'x7' panel on the roof where it's heated and returned to the insulated holding tank. To help reduce the extreme heat in the attic, two self-contained solar powered attic fans pull hot air up and out anytime it's light outside and the attic temperature is above 86 degrees.
Each morning as the sun rises, the panels begin generating energy. The first priority is the batteries. Once fully charged, the energy from the panels feeds the house. Excess electricity is placed back onto the electrical grid, spinning our meter backwards and crediting our account because of our net metering agreement with TECO. Should we experience a disruption of electrical service, our back-up system engages. The solar hot water pump is on a critical load circuit, so as long there's sunlight to re-charge the batteries, we'll always have hot water and electricity.
