The Green, Green Technology Of Home

For starters, its location in relation to the sun would maximize solar heat gain in the winter and minimize it in the summer. It would have a geothermal heating and cooling system, and it would also boast two different solar technologies — solar thermal for heating water and solar electric (photovoltaic) for generating electrical power.

In fact, even at 3,400 square feet, the home would be so energy efficient that it could be heated and cooled for less than $75 a month.

The house would also be furnished with products that are environmentally sustainable, like bamboo floors and tile made from recycled glass. The gardens would feature native plants that tolerate the region’s climate and soil conditions, and most of the gardens’ water needs would come from a 12,000-gallon cistern system that collects rainwater from the roof.

The Cliffs Cottage at Furman is Southern Living magazine’s first “green” showcase home. It was built on campus in 2008 to serve as a model of environmentally responsible design, sustainable building techniques and materials, and energy-saving systems.

The home features a passive solar design, which integrates an assortment of building features to reduce the need for cooling and heating and daytime artificial lighting. The home is situated along an east/west axis to maximize solar heat gain in the winter and minimize it in the summer. On the south side of the cottage, a long roof overhang shades the house in summer and allows the sun to heat the home in the winter months.

The home uses an energy-efficient, precast foundation, natural stone and two types of insulation to seal the home and preserve its thermal mass. The exterior stone absorbs heat that is slowly released after the sun goes down. The spray foam insulation, free of formaldehyde, seals off air leakage, moisture, airborne allergens and noise pollutants. The fiberglass insulation is environmentally sound, with a minimum certified recycled glass content of 25 percent. The pervious concrete, permeable brick and gravel pave used across the site in parking areas and main walkways allow stormwater to filter back into the soil instead of draining into streams and rivers.

The Cliffs Cottage has a geothermal heating and cooling system, which is the most environmentally responsible and energy efficient system available. The direct exchange ground source heat pump uses the earth’s constant underground temperatures to heat the home in the winter and cool it in the summer. Ground source heat pumps can reduce heating and cooling costs by as much as 50 percent, and they usually last three times longer than air source systems.

The Cliffs Cottage has two solar technologies — solar thermal for heating water and solar electric (photovoltaic) technology for generating electrical power. Heat from the sun is captured through two roof-mounted flat plate collectors, which is then transferred to an 80-gallon storage tank. The solar thermal technology can provide up to 80 percent of domestic hot water needs. Photovoltaic (PV) technology is the process where sunlight is converted to electricity.

Two PV modules on the garage roof are enough to power the entire house. Another pole-mounted PV tracks the sun as it moves east to west on one axis and north and south on another. In addition to the home, three other PV arrays help generate a total of 30 kW for the project. The solar features in the house are tied together by GridPoint, a computer-operated battery system that stores additional power and maximizes energy usage throughout the house. The solar technology, in fact, will produce more power than the house needs. The additional electricity created will be funneled to Furman’s utility grid.

The house is furnished with products that are environmentally sustainable and locally sourced, from the bamboo floors to the kitchen cabinets to tile made from recycled glass. Much of the furniture is constructed from reclaimed or sustainable harvested wood or trees removed for real estate development, and fabrics are made without toxic dyes. The bathrooms contain low flow showerheads and faucets.

The formal and organic gardens that surround the Cliffs Cottage are an important part of the project. The gardens feature native plants that can tolerate the region’s climate and soil conditions as well as typical ornamental plantings that are drought tolerant and easy to maintain. Most of the water needs for the gardens are supplied by one 12,000-gallon cistern system that collects rainwater from the roof.

In addition to Furman and Southern Living, the principal partners in the project are The Cliffs Communities, Duke Energy and Bank of America.

The Cliffs Cottage will be open to the public through the end of August.  After August, the house will be retrofitted as the university’s Center for Sustainability, which will provide office and meeting space for the university’s sustainability initiatives.