Wooler Mills House

The first misconception about going solar is that it is expensive.

The second is that it requires insanely complicated panels, transformers, and batteries. “We needed something simple, a way to use solar to cool the house more than anything,” explains Christopher Hays, principal of Hays + Ewing Design Studio, which he runs with his wife, Allison Ewing.“That’s how we were drawn 
to a passive solar setup.”

Passive solar systems use sunlight to warm or cool a house without the use of electrical or mechanical equipment, and are organized around the creative use and placement of materials such as heat-retaining concrete floors, sun-blocking louvers, and ventilation systems that naturally distribute air throughout a room or house. Because they use no additional energy beyond sunlight, passive solar systems have no operating costs or environmental impact and can cut energy costs for decades.

For their passive system, Hays and Ewing worked with a day-lighting consultant to study the trajectory of the sun throughout the year, plotting its penetration inside the house during each month. Fixed louvers were installed over windows to provide shade areas during summer. As the sun moves in winter, direct sunlight flows into south rooms, providing heat. For south-facing windows, Hays and Ewing installed three-foot overhangs and light-filtering trellises. High-density Plycem panels work like concrete to retain daylight heat and distribute it in the house throughout cool nights, keeping the architects warm inside the house.

Using natural convective currents, fresh air flows through the living areas downstairs and exhausts through the second-story windows. Windows upstairs at each end of the east-west-running hallways allow for cross ventilation.

“Since this is a passive system, it doesn’t completely take care of the temperature in the house,” explains Hays, “but it does protect a large degree—and that makes it totally worth it.”

Clifford Avenue Homes

The cost for solar systems is not only related to how elaborate the system is—it also depends on where you live.

Panel House

Taking advantage of Southern California’s sunny skies, architect David Hertz ingrained 
passive solar features in almost every detail 
of the Panel House for client Thomas Ennis.

Because the house is on a narrow 28-by-
89-foot lot that sits right on Venice Beach, 
Hertz was able to construct an entirely clear-span structural system and supplant walls 
with broad spans of windows. This is most 
strikingly demonstrated by the enormous 9-by-15-foot window at the front of the house that lowers to the basement on a worm-drive 
gear system, offering an unobscured view 
of the beach. Smaller windows sit on manual pivots, allowing occupants to moderate temperature with cooling seaside air. A thermostat-controlled skylight automatically opens throughout the day to release hot air that accumulates in the stairwell.

To insulate the house, as well as dissuade nosy neighbors from looking in through glass walls, Hertz covered the east façade in 3-by-30-inch prefabricated foam panels normally used for ice storage in the desert. Coated with aluminum on both sides and painted silver, the blocks lightly reflect summer sun and capture the changing colors of the sky.

While passive solar features are integrated throughout the front and sides of the house, the active solar system is confined to the roof. There, sharing space with an infinity 
pool, 14 south-facing PV panels and an inverter produce 2.3 kilowatts of energy per day, sending free electricity throughout the house if needed, or back into the grid. A thermal solar system boosts the temperature for water before it is sent to the water heater, further saving energy and costs.

“Enough ‘free’ solar energy falls to earth each day in the form of sunshine to supply current world energy needs for five years,” explains Hertz. “And the U.S. consumes a million dollars worth of energy every minute. We need to understand that conservation is the lowest-cost energy we have. Saving energy costs a lot less than finding it.”