Solar Settlement in the Vauban quarter in Freiburg (Germany), Elly-Heuss-Knapp-Straße. Credit: Claire7373 Andrewglaser

Is the Vauban district of Freiburg in southern Germany the world's best example of sustainable urban living? Construction of this intentional community began in the mid-1990s and it opened in 2000. By 2001, it had 2,000 inhabitants and now is said to have 5,000 inhabitants with over 600 jobs. "The Vauban district was created through cooperative decision-making, becoming a model of holistic environmental planning and eco-friendly living," Louise Abellard writes.

It developed from a squatted community that did not want to be removed by developers, who took the future into their own hands.

Cycle parks in Vauban.

The district was planned around green transportation (as with another city known as a global beacon of green urban planning, Curitiba in southern Brazil), because, besides consumption, transportation is the hardest ecological impact of development to reduce. While the district includes streets, cars hardly ever pass through, and car parking is not catered for. Residents who do own vehicles can park in a community lot on the edge of the district, unsubsidized by the car-free households.

Pedestrian and bicycle paths form a highly-connected, efficient, green transportation network with every home within walking distance of a tram stop, and all schools, businesses, and shopping centers located within walking distance. "When moving into Vauban, 57% of the households that previously owned a car decided to let their car go. All in all, 70% of the inhabitants live without a car in Vauban," Abellard reports.

A grassed tramway in Vauban.

All buildings must meet minimum low energy consumption standards of 65 kWh/m²a (i.e., at least half the average German energy standards). Public energy and heat are generated by a highly efficient woodchip-powered combined heat and power generator connected to a district heating grid. 42 building units are of the Passivhaus standard, consuming under 15 kWh/m²a. 100 houses adhere to a "plus-energy" standard, producing more energy than they use, with surpluses sold back to the city grid and profits split between each household.

Organic household waste is treated with an anaerobic digester. The place contains a unique ecological sewage system in one pilot project: sucked by vacuum pipes, faeces are transported into this digester, generating biogas, which is used for cooking. Grey-water is cleaned in biofilm plants and returned to the water cycle.

Importantly, the project is being monitored using lifecycle and regional material flow analysis with the GEMIS software. This is the first time that a complete urban neighbourhood has been analysed with respect to buildings, infrastructure, electricity supply, heat supply, water and waste, traffic and private consumption with a full life-cycle perspective and using regional data. The gathering of local data was possible for all areas except private consumption, for which national average data was used. Through this, the following provisional figures have been developed:

• Energy savings per year: 28 GJ (calculated as "CER", cumulative energy requirements).
• Reduction of CO2-equivalents per year: 2100 t.
• Reduction of sulphor-dioxide (SO2-) equivalents per year: 4 t.
• Saving of mineral resources per year: 1600 t.

Andreas Delleske's Passivhaus apartment block in Vauban.

Andreas Delleske lives in the first multi-family Passivhaus apartment block in Germany in the town. He was also one of the prime movers of the citizen's organisation, Forum Vauban, involved in the development of the settlement.

His involvement began in 1995 when it became clear that the squatted area of the town, a former French barracks, needed to be redeveloped. Like most of the initiatives in this book the impetus for change came from the bottom up via graassroots activism which then caused change at the top in legislation and planning.

An architect, Michael Gies, and a biologist, Jörg Lange, developed the idea of a people's forum to make sure that the people already living there had their views heard and could determine their future. They also realized there was an opportunity to create a low impact development and, together with experts in the world-famous Fraunhofer Institute for Solar Energy Systems (Martin Ufheil) and the Passive House Institute in Darmstadt, developed their plans.

A playground in Vauban.

The first house was completed in August 1999 and has been monitored ever since. The results of the monitoring show that the additional cost of making the building so energy-efficient was just 7%, which paid for itself in 10 years.

In Austria, about 300 passive houses have been scientifically evaluated and the extra cost of making them zero energy was anything from no cost to an extra 14 per cent. They also found that concrete should not be used, and that individual ventilation with heat recovery systems were not effective for reasons of cost and maintenance.

They make the point that combined heat and power is the most efficient form of energy generation to be used wherever there are clusters of buildings, whether for business or residence.

Vauban street market.

Freiburg

It's not surprising to learn that Vauban is the greenest area of the greenest city, Freiburg, in the greenest province, Baden-Württemberg, in Germany. Freiburg, a city of about 220,000 people and 155 km², is already known as an eco-city with the Green Party having the strongest presence there of anywhere in the country.

Freiburg's citizens are known for their love of cycling, with over 400 km of cycle paths, separate bikepaths, and over 9,000 bicycle parking spaces, including "bike and ride" lots at transit stations. The city has an extensive pedestrianised zone and a tramway network together with feeder buses. 70% of the population lives within 500 meters of a tram stop, and the trains appear every 7.5 minutes during rush hours with ticket costs subsidized to encourage use.

Traffic modes in Freiburg showing how cycling and walking has increased and car use decreased, a trend that is projected to continue into the future.

Waste levels have been reduced by almost 2/3 since 1988 with waste minimization, increased recycling (it is very easy to recycle everywhere), anaerobic digestion of organic waste and the residual waste burnt for energy.

The 5,000 hectares of forestry surrounding the town is managed sustainably and organically with certification from the Forest Stewardship Council. The city contains over 600 hectares of parks and 160 playgrounds providing greenery, recreation, and biodiversity. Changing the lawn mowing schedule from 12 times to only twice a year has "markedly revived the biodiversity in the meadows".

3,800 small privately owned garden allotments for the inhabitants to grow their own food lie on the outskirts of the city. This number is expected to increase, according to the new Land Use Plan 2020, the writing of which was done by citizens forming 19 working groups to discuss potential construction areas and make recommendations to the city council. Local food is also supplied by farm shops, a farmers' market, a local winery and distillery, beekeeping, butchers, bakers and plant nursery.

Shops and offices are located on the ground floor of the apartment buildings, allowing residents easy access, on foot or bicycle, to their daily needs, so that "no supermarkets will be constructed on green meadows".

Renewable energy production is encouraged with tax credits from the federal government and subsidies from the regional utility. In June 1995 Freiburg city council adopted a resolution that it would only permit construction of "low energy buildings" on municipal land, and all new buildings must comply with low energy specifications.

Every building in Vauban has solar panels on its roof.

Why is this city so green?

Part of the answer lies in the fact that it benefits from an unusually high concentration of specialist professionals working in sustainability, including the ICLEI (Local Governments for Sustainability), ISES (the International Solar Energy Society) and the City Mayors Foundation.

Perhaps, for the future of cities to be made sustainable, the only way is for this kind of expertise to be rolled out across every city in the world, through extensive programs of education, training and networking.