Stockholm, Sweden

The City of Stockholm hosted the first international conference on sustainable development in 1972 - which developed into the Earth Summit, and was hosted by Brazil in 1992, and by South Africa in 2002. Knowing that, you won't be surprised that Swedes are highly-motivated and well-educated about environmental sustainability. Sweden is one of the few countries in the world that enjoys a political consensus concerning its commitment to sustainability - no matter which political party is in office, sustainability is one of the top priorities.

Just south of Stockholm's city center is a new residential development called The Hammarby-Sjöstad. This project broke ground in 2000, and its estimated completion is in 2012. The plans call for construction of 8000 new apartments, corresponding to 20,000 new residents and 15,000 workplaces.

The Hammarby-Sjöstad's design concept is what the Swedes call ecocycles. The district has its own sewage treatment plant, which is built with nutrient recovering and extended production of biogas. The biogas is being sold back to residents in the form of fuel for domestic stoves and cars. The district is being heated mainly by heat pumps on treated wastewater, solid waste fired boilers, and liquid biofuel fired boilers.

The Swedes are also pioneering the modern method of urine separation and collection. This age-old technology recovers nutrients from human waste for use as fertilizer, thus changing the way we think about sewage