Nine years may seem like a long time, but if you are involved in energy policy within the European Union, time flies too fast. The European Union has set a goal of sourcing 20% of its energy needs by 2020, and many of the EU’s member states are struggling to meet that initiative’s goals.
One EU capital that is aggressively pursuing cleaner energy sources is
Paris. In 2007 the city adopted a Climate Action Plan that requires that 30% of its energy needs are met by renewables. The
plan will include strategies including
energy efficiency programs, building retrofitting, and even the installation of photovoltaic cells on street benches and insulated park kiosks. Paris is turning into a
clean energy laboratory: one
project transfers body heat from the city’s subway to generate heat in an apartment building. Now heat recovered from sewer pipes will warm a public school.
Last week a primary school launched a new heating system that draws energy from nearby sewer pipes. The joint
project between the city’s water department and two companies, CPCU and Lyonnaise des Eaux, employs the following steps:
- Wastewater from homes and business darts from shower drains, washing machines, and other sources through sewer pipes at a temperature ranging from 45 to 68 degrees Fahrenheit.
- In pipes where the sewage flows fast enough to maintain a constant temperature, a steel plate installed by Lyonnaise comes in contact with that waste water.
- That steel plate has a series of pipes through which a coolant circulates.
- The fluid in turn is directed to a heat pump that concentrates the heat as high as a temperature of 140 degrees Fahrenheit.
- In turn that heat is transmitted through the school’s HVAC system, which heats the rooms.
This process requires no combustion and is one that works in densely built areas or in neighborhoods with high heat consumption. A building that benefits from such a heating system must also be within 550 yards of a sewer in order to maximize the system’s energy efficiency.
Diagram for Wattignies' new heating system
For the Wattignies school that will benefit from this system, the new waste to energy source will cover about 70% of its annual heating needs, and prevent about 76 tons of CO2 from spewing into the atmosphere. The city plans to implement the system in additional schools, government buildings, and
eventually, the Élysée Palace, the current home of fashion model and singer Carla Bruni and of course, France's presidentPresident Nicholas Sarkozy.
This first such
system cost about 400,000 Euros, a steep sum. City officials, however, claim that up to 10% of Paris could eventually be heated by this method.
