a high turndown ratio (1:16) that precisely matches load. The Pyrotec hot water boilers have met their published performance ratings for combustion efficiency (up to 85%) since the biomass heating system went online in October 2011. A 5.2 MW natural gas boiler provides emergency backup for the biomass boilers, and a 650 KW diesel generator will ensure continuous operation of the entire dis-trict heating system in the event of an electric power failure. The boilers heat two 22,000 L buf-fer water tanks before heated water (90°C supply/50°C return) is distributed through a highly efficient, low-temperature hydronic heating network for district DHW and space heating. Pre-insulated underground piping in the 2.2 km system ranges from 8 in. in diameter exiting the boiler plant to smaller pipes feeding row houses (1 in. diameter) and other buildings throughout the site. Substations in each Cité Verte building distribute the appropriate amount of heat and calculate fuel bills for the individual units. Water flow throughout the network is driven by a 25 HP pump in the winter and a 5 HP pump during the summer, when space heat-ing requirements are significantly reduced. A Viessmann boiler control system inte-grates seamlessly with Smart Heat Network controls developed by Regulvar and project engineers Génécor and Poly-Énergie. The integrated system monitors the energy con-sumption data collected from individual units and district substations along with boiler data to optimize efficiency throughout the district. Each dwelling is equipped with a moni-toring unit that provides information on daily energy consumption to raise residents’ aware-ness of their energy usage and encourage energy conservation in the neighbourhood. LA CITÉ VERTE: A LOOK AHEAD Residential units in three renovated build-ings and one new structure constructed during the first phase were completed in late autumn 2011. The first residents moved into the renovated buildings at the beginning of December. The construction of new buildings in Phase 2 will begin in 2013. Representing over $300 million in in-vestments, La Cité Verte has demonstrated the feasibility of taking an environmentally responsible approach to urban develop-ment by addressing urban densification, rainwater management, energy efficiency of buildings, waste sorting, transportation management and the preservation of green spaces. When completed, the project will use 30% less energy than conventional de-velopments, and the consumption of pota-ble water will be cut in half – representing a reduction of 131,000,000 litres of water per year, or the equivalent of 52 Olympic-sized pools. A $22.7-million investment by the Quebec government, a $4.7-million grant from Natural Resources Canada’s Clean Energy Fund and financial assistance from Hydro-Québec affirm the vision and for-ward thinking of the Quebec community regarding sustainable development. By in-tegrating aspects of sustainability and green technologies in the initial planning stages, La Cité Verte has become a model for future developments in the province and the first green technology showcase in Eastern Can-ada. The site is also expected to inspire new planning strategies and play a leading role in the adoption of sustainable development «À>VÌViÃÊ>VÀÃÃÊ+ÕiLiVÊ>`ÊLiÞ`°ÊU This article was submitted by Viessmann Manufacturing Co. Inc. biomassenergylab.com GLOBAL LAB SERVICES International & Domestic Biomass Fuel Markets ISO 17025 Accredited for ASTM and CEN/EN Standards TIMBER PRODUCTS INSPECTION Accredited by the American Lumber Standard Committee as a Testing Laboratory and an Auditing Agency for the Pellet Fuels Institute’s Densified Biomass Fuel Standards Program. 1641 Sigman Road Conyers GA 30012 218-461-2579 14 Canadian BIOMASS SEPTEMBER/OCTOBER 2012
Canadian Biomass September/October 2012: Page 14
