jeudi 5 juillet 2012

An inspiring visit to Grenoble, Echirolles and Gières

It is for partners of the INTERREG IVC RE-GREEN project that Energy Cities organised in June a 2-day studytour on retrofitting and energy efficiency in buildings. Return in pictures...

Partners of the RE-GREEN Project

Echirolles, High Environmental Quality Town Hall

The visits started in Echirolles, the city that decided to allocate 10% of its public investements to energy conservation measures, including a strong focus on the retrofitting of its public buildings.

Visit of the HQE Building with Yannick Ménard, Environment and Sustainable Development Department

Labellised Cit’ergie-eea® label in 2007, Echirolles is well known for its Local Agenda 21 featuring strong public participation as well as for its involvement in the Grenoble Metropolitan Council’s climate plan. The municipality has made sustainable development one of its top priorities and is committed to dividing its greenhouse gas emissions by 4 by 2050. Echirolles sets the tone with its beautiful Town Hall, built in 2006 according to the HQE frame of reference (more info in French). Nearby, the "ZAC Centre 2" district is a concentrate of sustainable constructions and planning ((more info in French)->doc6511].

Since 2009, Echirolles is the lead partner of a consortium of 9 cities and 1 region for the URBACT II Cash project, to which participate 2 other Energy Cities members : Frankfurt (DE) and Utrecht (NL) . The aim of this project is to look for new solutions to renovate social and affordable housing units, in order to improve their energy efficiency (EE) and to influence users’ behavior through citizens’ involvement. More info...

Low-energy retrofitting works at the Jean Jaurès nursery school

Visit to the HRV (Heat Recovery Ventilation) technical room with William Kay, Operations manager at the City of Echirolles’ Building and Network Department.

In 2008, as an intermediate step towards factor 4, the City of Echirolles undertook to reduce its greenhouse gas emissions by 30% by 2014. Applying this decision to municipal building thermal retrofitting resulted in a two-step process :
1. preparation of an energy audit per building and presentation of possible “low energy” scenarios.
2. carrying out building thermal retrofitting works.

The energy audit for the Jean Jaurès school complex was performed in 2007 and the City Council started retrofitting the nursery school in 2008. This school is typical of the 1960s with a design that makes retrofitting the building envelope relatively easy. The following works were carried out : facade insulation (15 cm of graphite-enhanced polystyrene), attic insulation (35 cm thick glass wool), floor insulation (12 cm of projected rock fibres) and replacement of all single-glazed joinery. The installation of an HRV system with 68% efficiency and the replacement of all light fittings are also worth noting.

These works should contribute to improving the building’s energy rating from E to B on the DPE (French energy certificate) scale, leading to CO2 emission savings of 33 tonnes/year.

The SIERG office in Echirolles : an example of factor 4 retrofitting using passive solutions to improve summer comfort.

Discovering the building’s “double skin” and thermal solar sensors with Jean-Pierre Palmas, in charge of water conveyance at the SIERG

The SIERG (Syndicat Intercommunal des Eaux de la Région Grenobloise – Intermunicipal water board from the Grenoble area) office is located in a 1984 building with an envelope made of curtain walls with extensive surface areas of glass. Minimal insulation complying with the 1980s lenient requirements made the building extremely uncomfortable in summer.

An energy audit performed in 2005, followed by a bid for public procurement tenders in 2007, led to the selection of a solution that went well beyond the programme’s requirements of dividing energy use by 4 !

The following technical solutions were implemented : reduction of glazed surface areas, external wall insulation, replacement of all joinery, installation of solar protection, improvement of roof insulation and watertightness, introduction of vegetation on terrace roofs and installation of an HRV system using groundwater as a coolant and PV panels.

The project won the Prebat “low energy demonstration buildings” call for projects for the exemplary features of its retrofitting work.

ZAC De Bonne : an eco-neighbourhood with increasing quality of life !

First discovery ... under the sunshine and in the fresh morning air
On the left in the background is the "Bonne Energie" building, a positive energy office building.

As an introduction to the neighbourhood tour, we were presented with the Grenoble Alpes Métropole’s Climate Plan as well as actions from the Local Energy and Climate Agency. With Hélène Poimboeuf, Environment officer at the METRO Urban Policy Direction, Marie Filhol, Director of the Local Energy and Climate Agency and Jérôme Buffière, project manager for the Local Agency.

Social and functional mix, uses and governance...

SCovering a surface area of 8.5ha, the ZAC De Bonne development area includes : 850 dwelling units, of which 35% is social housing, a shopping centre (16,000 m² NIFA), a students’ residence (3,100 m² NIFA), 2,500 m² of office space, an 80-room hotel, an experimental and art film theatre due to open in September, a passive solar primary school (17 classes) and an old people’s home.

The first residents moved in as of 2008. All new residents receive a good practice leaflet about their dwelling and building prepared with the support of the Local Energy Agency. A welcome meeting is organised in each building in the presence of elected representatives (at least the deputy mayor in charge of town planning as well as the Mayor whenever possible). Interested residents are given the opportunity to monitor their energy use and are regularly questioned about the living quality of their dwelling.

Luxuriant vegetation for the gratification of the senses and improved quality of life

The former De Bonne barrack site has been reclaimed by Nature, the 5 ha urban park and gardens providing both residents and visitors with a haven of green space in the centre of Grenoble.