January 04, 2010
by Steven Castle
Mike McDonald is proud of his green home—and justifiably so. The stunning 4,600-square-foot Margarido House is the first custom home in northern California to achieve the highest “Platinum” rating in the LEED (Leadership in Energy and Environmental Design) green homes program, and it exceeds California’s energy-efficiency Title 24 requirements by 55 percent.
It has all the green amenities: 4.2 kilowatts of solar panels, a solar thermal system that provides domestic hot water and that for a radiant-floor heating system, and all kinds of green building materials. But what’s the one green technology McDonald likes best?
That would be a home control system that helps him and his family of four operate all the heating and ventilation equipment, plus an energy-saving LED (light-emitting diode) lighting system, motorized shades, as well as some energy-efficient audio/video components.
“I love how easy it is to control everything in the house, and to control every light in the house from a couple of different locations,” he says. “I can dial in the HVAC more easily than using standard programmable thermostats. And it’s really easy for my whole family to use.”
The Colorado vNet home control system features several touchpads and a couple of in-wall touchpanels. It operates over Category 5 network wiring, which made it simple to install and to maintain, says McDonald’s electrician and electronics installer, Jean-Paul “Dusty” Fisher of JPFisher Electric of Martinez, Calif.
“It can do about 95 percent of what larger systems do, but it’s more affordable and programmer-easy,” says Fisher. “It can control anything and make it simplified, and you don’t need special [bus] wiring for it.”
Along with the solar array and passive solar features, such as optimal siting of the house to increase solar gain for heat and light, the control system helps the McDonalds pay less than $70 a month on electricity bills.
Passive solar features are an important part of the design. For example, a striking metal awning mesh that supports a patio above blocks a great deal of light and heat from the high sun in the summer, precluding the need for cooling. Yet the position of the same awning allows that light and warmth to enter the house in the winter, when the sun is lower. When the glare gets to be a little too much, motorized Lutron shades automatically descend to block the light.
In addition, the house is built into a hill, so the back of it is below ground and effectively cooled by the earth. Fans positioned at the back wall help circulate the cool air, while exhaust fans expel warm, stale air. The fans are designed to be activated by the Colorado vNet system.
“My take is that the passive stuff makes a big difference in the energy efficiency of the home,” says McDonald. “When there is too much natural light, the technology kicks in with things like the motorized shades. The technology can make it more convenient to be green, and if it’s more convenient, it will be used more.”
McDonald estimates that the electronics systems in his home have probably helped shave another 20 percent from his electricity bill.
Light warms the space and reduces the need for electronic lighting, but later in the day when the glare is too much, Lutron shades descend to help filter the light. Credit: Mariko Reed
Steven Castle is Electronic House's managing editor. he has been writing about consumer electronics, homes and energy efficiency topics for two decades. He is also the co-founder of GreenTech Advocates