GCT Featured Articles
Freiburg, Europe's Solar City
Renewable Energy - Solar, Biomass, and more, in Freiburg
Freiburg is known as Europe's "solar city". Solar energy in Freiburg has guaranteed feed-in tariffs (thanks to Germany's Renewable Energy Law). Vauban, a city district in Freiburg, in which the majority of homes run on solar and solar thermal energy generated on-site, is known as one of the most sustainable city districts in the world. The city of Freiburg was home to the Solar Summit 2013 to focus on the global energy transition; an event for investors, scientists, utility executives, and officials from various governments, in which new solar thermal technologies were featured.
In addition to using solar power as a major energy source, Freiburg uses biomass (as well as wind and hydroelectricity) for the majority of the rest of the city's energy needs. Over 40% of Freiburg consists of woodland and green spaces, and over 5000 hectares of forest surrounds the city. Biomass energy is generated from wood and forestry byproducts in Freiburg, but the city also turns trash into biomass energy to power residences and businesses. Biomass plants in Freiburg substantially rely on methanization; a process which turns organic matter (in the case of Freiburg, mostly forestry/agricultural waste, and garbage from residential/ commercial buildings) into biogas. Methanization-based biomass plants at the edge of the city are fed with collected organic waste to generate energy (over 36,000 tons per year) provided by city residents (mostly farming, kitchen, and garden waste).
Wood is burned, in addition to waste, in the biomass plant in the city district of Vauban; landfill gas and organic waste are both used in the other biomass plants in Freiburg. These biomass plants, along with another biomass plant in Freiburg that uses mostly rapeseed oil to produce biodiesel, are designed to create combined heat and power (cogeneration) to supply district heating and electricity in the city.
In addition to biomass power plants in Freiburg, are smaller anaerobic digesters on farms in the city, which also convert organic matter to energy. Biomass plants and solar energy are not the only sources of renewable energy in Freiburg. Other than solar and biomass, small wind farms and hydropower projects also provide energy to the city.
This snippet from BBC summarizes some of Freiburg's major accomplishments in sustainability over the last 30 years:
Freiburg has quickly developed as an environmental economics and solar research hub with a packed green CV:
• 1994: Builds Heliotrope: the world‘s first energy-plus house
• 2002: Elects Germany’s first Green Party mayor, Dieter Salomon
• 2010: Wins national award for its climate protection efforts
• 2012: Named most sustainable city in Germany
• 2017: New Town Hall becomes world’s first public building producing surplus energy
Here's more information about Freiburg's Town Hall:
During the course of the year, the building generates more energy than it consumes. The excess energy is fed into the city grid. In accordance with the strict criteria of the PassivHaus standard, the primary energy demand of the town hall for heating, cooling, ventilation, and hot water supply [is sourced from renewable energy and passive heat gains].
...electric energy is generated by photovoltaic panels on the roof and in the facade. The energy for cooling and heating is obtained from a geothermal installation. Thermal mass activation is used for heating, which can be individually controlled in each office. The mechanical ventilation has been enhanced by highly efficient heat recovery.
Green Building and Alternative Transit in Freiburg
Freiburg remains at the forefront of green building technologies, mandating that all new construction uses only the latest cutting-edge energy efficiency designs- passivhaus standards. Energy conservation is central to all new building in the city, and energy efficient retrofits are being applied to existing structures. Residential recycling programs go beyond standard measures, as compost is also collected in the form of kitchen and garden waste.
Freiburg promotes biking and walking, which have become increasingly popular means of alternative transit in the city. Freiburg features a pedestrian-only zone in the city center, where no cars are allowed. Biking accounts for over 1/4 of all transportation in the city. Over 300 miles of bike paths in the city help to reduce automobile use.
In order to help make alternative modes of transit even more attractive, all roads in Freiburg, other than major roads, have a max speed limit of 50 km/h. The city offers the Regio Card (Regiokarte), which enables residents full access to all of Freiburg's trams, streetcars, trains, and buses. Increasing city residents' ease of access to Freiburg's mass transit options, 70% of the population live within 1/2 km from a tram stop.
Green urban planning is paramount in Freiburg; and the city has designated green areas as a priority in land-use decisions. Almost half of the city remains protected as parks, forest, or green landscaped spaces- a big reason why biking and walking remain so popular in the city. In the city district of Vauban, entire neighborhoods run on energy provided by rooftop solar panels, as well as a municipal biomass plant.
Careful urban planning helped to create a city layout in Vauban which lends itself to cycling as the primary mode of transit. The terms “filtered permeability” and “fused grid” refer to a plan that ultimately means connected streets throughout the town, as well as plenty of pedestrian and bike paths. Residents primarily live in co-op buildings, such as the “solar ship”, a large area of co-op buildings that run strictly on renewable energy.
Freiburg has a goal of achieving 100% renewable energy and carbon neutrality for the entire city by 2035.
Please click & read...
Europe's most sustainable city district (the city district of Vauban in Freiburg)
and for more on Vauban- The World's Most Successful Model for Sustainable Urban Development? via Smart Cities Dive