Freiburg is known as an ecocity. The newly built neighbourhoods of Vauban and Rieselfeld were developed and built according to the idea of sustainability. The citizens of Freiburg are known in Germany for their love of cycling and recycling.

This past December, as climate talks in Copenhagen commenced, I sat in talks in Istanbul listening to local government representatives, building professionals and academics discuss concrete actions that can and have been taken to reduce greenhouse gases in cities around the world. The 8th annual Ecocity World Summit posed a compelling alternative to the fights and frustrations that mired the climate talks of Copenhagen in conflict. Cities represent about 75% of greenhouse gas emissions worldwide, and the birth of the “eoocity” concept a few decades ago may have marked the beginning of our most tangible solution yet. From recycling, wastewater treatment and green building to smart urban planning, public transit and renewable energy generation, ecocity plans and ideas have emerged with a list of seemingly “no-brainer” action items to pursue.

While in theory, the “ecocity” may seem like a very straightforward concept, in practice the challenges prove tough to transcend. The urban and suburban sprawl that plagues regions in the United States, Canada, Australia, and New Zealand may seem like an almost insurmountable barrier to reducing carbon emissions. However, in Istanbul, a city of 13 million and growing, sprawl is compounded by the fact that much of the development is unplanned. This is also true for other mega-cities like Rio de Janeiro where families often add stories to their own homes, creating unsound structures that may collapse during natural disasters. Such unplanned settlements also make it difficult to create underground tunnels for a metro system, as there may be no record of where gas and electricity lines run underground. Traffic and a lack of environmental practices like wastewater treatment are also a major issue for such megacities.

Historical considerations also present challenges, as the rich cultural heritage of ancient cities demands a certain authenticity of design. Moreover, as cities like Istanbul go to dig tunnels for eco-features like an underground metro, they may discover archeological treasures that force them to stop digging.

In modern cities of intense density like Hong Kong, Tei Pei, and Singapore, a lack of space to erect renewable power generation and urban farming operations create challenges to meeting energy and food demands without importing food and energy. In many developing nations, a lack of laws to regulate pollution and a lack of enforcement for existing environmental laws also create little incentive to move towards renewable energy. Some regions lack the resources to produce renewable energy, forcing them to make a decision between a local energy economy and a clean energy economy.

Approaches to creating an ecocity to solve these problems vary. According to Elizabeth Rapoport of the University College of London, there are three main categories of ecocities. Ecovillages, such as Cerro Gordo in the U.S. are small pastoral communities. Masterplanned ecocities such as Tianjin, China and Masdar, Abu Dabi, are new cities that incorporate ecological principles from day one. Models in already retrofitted ecocities like Curitiba, Brazil and Freiburg, Germany have the greatest potential to transform the already developed world, where builders and planners will have to make improvements on the existing infrastructure and building stock. Taking lessons from other more advanced cities will be an important step in the process if cities want to avoid reinventing the wheel. Conversely, avoiding some of the mistakes that more established cities have made will be crucial for nascent cities in the developing world.

The term “ecocity,” like other trendy terms including “green” and “sustainable” will likely be the subject of abuse over the coming years and decades. While there is no one-size-fits-all solution for the cities of the world, the sooner the international community comes together to define an ecocity that really does live up to the name, the more clear direction and success cities will have in reducing greenhouse gas emissions and pollution while improving the quality of life for their residents. Hopefully the local governments involved in redesigning our cities can learn to work together more effectively than did the participants in Copenhagen. Unfortunately, that’s a low bar.