After looking at lists of bad building design choices, I’ve gathered together top 11 promising appropriate technologies I’ve seen in use for residential and commercial buildings. For those of you not familiar with the term, appropriate technology generally refers to technology that is small-scale, decentralized, energy-efficient, environmentally sustainable, locally controlled, and people-centered (Wikipedia).
Appropriate Technology #1: Solar Photovoltaics (PV)
Solar has never been cheaper than now. Buying a solar array is like having your own oil field, except it sits on the roof, is completely quiet and is emission-free. Investing in a solar array is like buying the next fifty years of power at today’s prices. We all know that power will only get more expensive, so why not lock in for the long-term while helping the planet at the same time? Homes built with the Passive House methodology are so efficient that they actually use PV power to provide supplementary heating.
Appropriate Technology #2: Solar Thermal
This is a low tech way of meeting the majority of your hot water needs without using any fossil fuels. The technology has been around for a long time and is solid and reliable. Check out simplesolar.ca for more details.
Appropriate Technology #3: SolarWall
Turn that liability (a hot southern wall) into a valuable asset. The SolarWall® is a Canadian technology that turns the cladding around buildings into a hot air collector. A bypass vent keeps the building cool in the summer. When you factor in the price of siding and apply it to the price of a solar wall, the cost is quite competitive and is a quick return on investment (3-6 years). In addition of being able to meet close to 50% of your heating needs, it is ultra durable and will protect your building for years to come.
Appropriate Technology #4: Solar Roof
Essentially a solar roof is a heating system that’s integrated into the roof of a building. Typically metal roofing is installed on top of a Tyvek™ building fabric with an airspace between the roof and the metal. A dark metal material is used to absorb heat while air ducts are placed into the attic to harvest the hot air collected below the roof surface. The air is injected into the house or below the main slab and non-perforated weeping tiles to heat the floor. For regulation, a thermostat is installed under the metal roofing while a fan turns on or off based on the air temperature.
This is very similar to a solar coffin, which a friend of mine uses to keep his home warm.
Appropriate Technology #5: Standing Seam Metal Roofs
I’m a huge fan of metal roofing. There are a ton of unique things you can do with it, such as harvest rain, collect solar hot air, and keep your home cool in the summer. If designed properly, your investment will last a lifetime. Having said this, I am only a fan of standing seam metal roofing. The inexpensive roofing is held down with metal fasteners that have neoprene washers to seal any holes made.
Appropriate Technology #6: Earth Tubes
I’m infatuated with the simplicity of earth tubes. Earth tubes are plastic pipes that convey cool underground fresh air into the home. They are typically buried below the frost line where the temperature of the earth is constant. In the winter, they preheat incoming frigid winter air (lets say, from -30˚C to -10˚C), while in the summer they can keep an earth fridge cold or air condition your home.
Read about a case study where we designed a heating system for a home using a variation of the earth tube design here: Annualized Geosolar.
Appropriate Technology #7: Basement Rain Cistern
This is an element that you don’t see all that often – the only place I’ve seen it is in old homes in Saskatchewan. My grandmother’s house had a cistern that collected all the rainwater used for their garden. It was built with cinder blocks and sealed with tar (not the greatest!). For me, basements are not typically the nicest place to live anyways so using it for rain storage seems like a great use!
Appropriate Technology #8: Composting Toilet
I’ve come across a lot of composting toilets in the last five years. The main complaint for most commercial ones is that they struggle to deal with all the liquids sent their way. If you are going to use one, I recommend setting up a piss bale for the men, or finding another urine harvesting/diverting system to reduce the liquid load (i.e. a waterless urinal).
The two composting toilets I’ve heard good things about include The Phoenix and Clivus Multrum (shown above). I’ve used both and they work well. They’re not cheap to set up, but they will last forever!
Appropriate Technology #9: Sunfrost RE-fridge
The Sunfrost Fridge is one of the world’s most energy-efficient refrigerators. It utilizes a very simple design: More insulation in the walls and less energy is needed to keep the fridge cool. Check them out, as they might make sense for your next off-grid project.
Appropriate Technology #10: Rayburn wood stove
I was introduced to the Rayburn stove in Australia and it’s awesome! It’s a cook stove, oven and hot water heater all in one. This makes so much sense in our cold climate. They’re not cheap, and I’m not sure if they are CSA approved in Canada, but they’re definitely worth checking out.
Appropriate Technology #11: Wall Therm
I was just sent information on the Wall Therm recently and I’m pretty impressed with what I’ve seen so far. It is a fireplace with a water jacket so it can heat your living room, floors, and provide domestic hot water all at once. They cost around $6,000 and are sold on the east coast. Check them out here.