Great Examples of Sustainable Design
What Makes These Design Examples So Great?
What do you think of when you hear the phrase "sustainable design"? Do you maybe picture hybrid cars, or artsy modern green buildings?
The best examples of sustainable design, I believe, are products that are above all simple and purposeful. Simple, in that they use basic natural laws and principles, and are cheap to make. (So we're not talking nanotechnology, for example.) Sustainability is not just about preserving the environment, it's also about meeting human needs. There's a lot of interest when it comes to "sustainable design" in figuring out how we can still build our big homes and drive our cars without a guilty eco-conscience - the rich have the money to invest in that. But designs that help the poor meet their needs must be cheap and simple if they are to be perpetuated.
I want to highlight three sustainable designs that both serve an important human need and help to lower our footprint on the earth. And they're simple - two of them technically can be made and used in your backyard!
Th Peepoo by Peepoople
The Peepoo Bag
The Peepoo bag is a great example of a simple sustainable design, serving a highly important need. (And it's okay to laugh at the name!) Created by the Swedish group Peepoople, the bag aims to solve water contamination issues in slums and disaster hit areas of the developing world. The World Health Organization claims that about 40% of the world population does not have access to a toilet. One child dies every 15 seconds from water contamination, and this is largely due to human waste contaminating the water supply.
The bag has a large contingent of possible users: in 2003, the UN calculated that slums made up one third of the world's urban population. In slums, plumbing and sanitation are nonexistent, and human waste leaches into the drinking water, becoming a huge health hazard. The bag has so far been used in in Kibera, one of the largest slums in the world, located outside of Nairobi, and in Haiti after the 2010 earthquake when sanitation infrastructure was interrupted.
The Peepoo is a slim biodegradable plastic bag with an inner lining made of urea. The bag is made for a single use – one defecation and/or pee, and then it's knotted at the top and disposed of, preferrably offsite in containment. Urea is the main ingredient in modern synthetic fertilizer, and it speeds up the breakdown of the feces or urine into ammonia and carbonate. Effectively, in 2 - 4 weeks the bag decomposes and hygienizes the human waste to the point that it is no longer a health threat, and can in fact be used as a fertilizer. Peepoople is also looking to promote urban agriculture in slums using the Peepoo-made fertilizer, possibly turning what was once a severe problem into an asset.
It’s not often appreciated just how much thought goes into the design of sustainable farms. A farmer looks at her/his operation as one big ecosystem, in which each piece serves multiple purposes to maximize profit and eliminate waste. Aquaponics is the raising of fish (aquaculture) and plants (hydroponics) together in tanks of water. Essentially it mimics aquatic systems found in nature, but okay - we'll say we "designed" it.
Wild fish stocks are being rapidly depleted. Oceans are fished at unsustainable rates, to the point that some scientists think certain populations won’t ever recover. Now half of the fish we buy in the grocery store is farmed, and these farms can pose their own environmental hazards.
The design can vary somewhat. In the pictures to the right, you can see that in the Growing Power system the plants and fish tanks are separated and the water is circulated between them. In the floating raft system below, the plants are right on top of the fish tank.
The cycle works the same in each design: the fish poop, it sinks to the bottom, and the water is pumped through a second tank holding gravel or another such medium. Bacteria hang out in the gravel and break down the fish waste into a useable form of nitrogen. The water is then 'recirculated' back into the top of the tank (or a separate tank) where the plants absorb the nitrogenous fertilizer. Excess waste can be funneled out and applied to terrestrial crops or other plants in the greenhouse. When the system works perfectly, it should require only fish feed and some form of energy for the pump. Very minimal amounts of water are lost to evaporation.
If the aquaponics tank is located in a greenhouse, the water serves an extra service as “thermal mass.” Water holds heat better than air, so at night when outdoor temperatures drop, the water retains heat from the day longer and releases it slowly, mitigating nightly temperatures in the greenhouse.
See more aquaponic designs and learn how to build a system yourself at Backyard Aquaponics!
Mainly promoted for use in developing countries, but some people like to use them in their backyard for a little cookout. Solar Cookers International is a small non-profit based in Sacramento dedicated to bringing solar cooker technology to rural developing world areas. See their informative National Geographic video.
In the developing world, indoor air pollution is a bigger problem for people’s health than outdoor, because they use fires to cook and the soot and smoke gets in their lungs. The World Health Organization has estimated this pollution leads to the deaths of 2 million women and children each year. The use of wood for kitchen fires also creates a local deforestation problem, decimating animal habitat and other ecosystem functions. People (usually women and girls) have to walk farther and farther each day to gather wood, taking time away from school or other economic activities.
This has to be the simplest concept out of the three, although like aquaponics, it comes in various designs. Solar Cookers International says they make on that costs $5, and will last two years. Shiny metal – literally aluminum foil - directs sunlight into a dark pot or box, which absorbs the energy and turns it into heat. (Dark colors are more effective at converting UV rays to heat than light colors.) A glass covering over the box may be used to create a greenhouse effect – sunlight can penetrate in, but the glass keeps the heat from escaping out. And it gets sizzling enough to cook anything! Meat, bread, rice…it can also boil water, effectively decontaminating it of certain pathogens.
On Amazon a solar cooker costs about $250, but I also found directions on how to build your own solar cooker using just foil and cardboard!