Proven Passive Solar, Low Cost, Low Energy Homes
Passive solar energy for homes is so passive it goes almost unnoticed on the menu of opportunities to cut greenhouse gas emissions. Quiet, mild mannered and laid back, it’s one of the easiest and lowest cost ways to build a low energy home. Just ask Bruce Brownell, the founder of Adirondack Alternate Energy. He’s built more than 350 of them. His simple, well thought-out passive solar home design has been proven for 30 years. All of them are successful at dramatically cutting heating energy costs while providing a healthy environment to live in.
The recipe for a Brownell home - with a little editorial liberty - seems straight forward enough:
--- Start with a simple architectural form like a box or a long rectangle that’s easy to heat or cool. Air will flow easily to all ends of a simple shape, not so much to say perhaps L or a T. (Your house design can be quite traditional by the way. No need for ultra modern architecture.)
--- Make sure there’s a long roof overhang. Let the summer sun cast a shadow on the house as best it can.
--- Orient the house to face south into the sun (Or North if you’re living in, say, New Zealand.) Plan on big energy-efficient windows on the sunny side; little windows where the sun never shines. Use high quality double glazed vinyl casement windows with low E glass. Casement windows seal better than double hungs. Low E windows keep infrared heat in, or out, and reflect ultraviolet light.
--- Forget about a basement. Build the home on a 12 inch thick concrete slab. Dark damp basements, whose origins trace back to root cellars (a cool place to store potatoes), are generally second class spaces anyway. That slab, as simple as it is, is part of your heating system. (If you want extra storage space build a big garage or shed.)
--- Before the concrete is poured for the slab, a scorpion-like network of ductwork is laid within the form. That ductwork will eventually transfer heat to and from the house, making the slab a thermal energy storage device: a battery for heat.
--- Build the house envelope and insulate the dickens out of it. Apply 4 inches of rigid foam insulation panel to the sides, the roof and all around that thick concrete slab, including its underside. Without siding, trim and roofing materials the house should look and function like a foam picnic cooler.
--- Then do something radical with the house design: Allow the attic space to become a heated living space. Insulated snugly on the outside with all that foam, the attic will become yet another key component in the overall passive ducted air heat transfer system. It will become a temporary holding area for heat that rises from the whole house.
--- Add a big blower and large duct to move the warm air from the attic downhill into the slab ductwork.
--- Add a solar thermal hot water system. It will supply your domestic hot water needs and supplement the passive solar heating system. Then add to that a small propane, natural gas or electric boiler for back-up heat should things get really cold outside.
--- Install a wood or pellet stove to dry out your wet boots and warm your frozen, damp feet.
--- Finally, add a few off-the-shelf items like Energy Star rated appliances and certainly low energy lighting. (I like LEDs for directional lighting, halogen energy savers (HES) for lights that are switched on and off frequently, and fluorescent and compact fluorescent lamps for those that tend to stay on for long periods, hours on end.)
Whip it all up and there you go, a snug-as-a-bug-in-a-rug home that's pretty much as green as a zero-net energy or green home, but built for the same cost as a conventional one.
Once you move in, this is how the whole thing should work:
Sun coming in through those big sun-facing windows heats the interior of the house. The thick insulation and first rate weather-stripping keep the cold out and trap the heat in. The hot air rises into the attic space where it’s pulled out and pushed back down through the house into the scorpion ductwork in the concrete slab. Slowly the heat from the air, and the warmth that it gets from sunlight striking the floor lying atop the slab, warms the entire mass of the slab. The air keeps moving, however, back into the house to filter and circulate it and pick up more heat.
When the sun goes down, or is hidden behind clouds, the slab will release some of its heat into the ductwork and warm the house. If there’s not enough heat in the slab the solar thermal hot water system will kick in, adding more heat through radiators strategically spaced in the ductwork. Further, if the solar thermal hot water system isn’t doing the job the conventionally-fueled boiler will assist the solar hot water system. Finally if your home is in the middle of a three day snowstorm you can always throw a log or two into the stove.
More or less this is pretty much how one of the latest Bruce Brownell homes is built and works. That home, the Kosmer House, in Upstate New York in Fly Creek, just outside of Cooperstown (the Baseball Hall of Fame town) was built by John Kosmer, Home Improvement Editor of Victorian Homes magazine.
The 4000 square foot 30 x 50 foot house with attached 30 x 34 foot garage (also a passive solar design) was built for $125 a square foot - comparable to a traditional home. But energy costs for heat are $2.50 a day. That’s about 70 percent less than a conventional home of the same size. And Upstate New York isn’t known for balmy winters. In fact, the opposite.
Adirondack Alternate Energy
The Kosmer Solar House Project : The Passive Solar Home
Simonton Windows (ENERGY STAR qualified low E double glazed windows used in Kosmer House)
International (Exclusive distributor of Baxi products in North America
for Baxi ENERGY STAR qualified Luna 3 boiler with integrated solar hot
water panels used in Kosmer House.)
Dow Tuff-R Rigid insulation