Green Energy

Sustainability and conventions are becoming increasingly popular in this day and age. Both physically and environmentally, awareness about global warming has spread across the world and there is pressure on the leading landmarks of cities, such as congress centres and convention spaces to ‘Go Green’. MICEtalk looks into the sustainability efforts made by one of the newer venues, the Swiss Tech Convention Center (STCC).

For decades, École polytechnique fédérale de Lausanne (EPFL) has been committed in favour of sustainable development on its campus. It uses water from Lake Geneva to cool and heat its buildings; it has a 15,000 sq m installation of photovoltaic panels on its roofs; it lacks hot water in washbasins; it preserves ecological green spaces; it promotes soft mobility with close to 80 per cent of commuters walking, biking or using public transport to reach the centres. For its new Convention Center, EPFL went even further in its systemic and innovative thinking by making the best possible use of all energy sources available in the vicinity and by showcasing emerging energy technologies.

Lake water for heating and cooling

EPFL is cooled and heated with water from Lake Geneva, with a distribution network of cold and low-temperature hot water produced by heat pumps. The core idea of the STCC’s energy concept, originally designed by EPFL operation service, was to exploit the heat of the water used to cool EPFL’s buildings to heat the STCC, with a heat pump. This use of by-products of EPFL’s cooling water enables to produce more heat in winter and cold in summer. At the end of this heating and cooling circuit, the water is returned to the lake via the river Sorge that flows close by, without causing any harm to the environment.

The sanitary hot water used in the STCC is 100 per cent renewable. It is produced by solar panels on rooftops of the nearby student housing and shops, as well as by heat pumps recovering waste heat from ventilated air or by the heat produced by refrigerators.

Photovoltaic panels: a world’s first

On the western façade, a transparent and coloured glazing performs the double function of solar protection of the façade and producing electricity. It is the first large-scale implementation of the dyed cells invented by Michael Grätzel, professor at EPFL and manufactured by Solaronix, an EPFL spin-off. They produce 2,000 kWh per year, while preventing the inside of the center from overheating. On the roof, a traditional photovoltaic installation will complete the system with 250 kW of power.

Natural light

Both for users’ comfort and saving energy, STCC primarily makes use of natural light, even in the plenary room that seats 3,000 people. In the entrance hall, the western façade’s photovoltaic glazing with dyed cells diffuses multicoloured, shimmering reflections.

Artificial lights make use of the latest technologies available and supply remarkable energy performances. The electricity EPFL consumes is from 100 per cent renewable material.

Sustainable mobility

The STCC can welcome up to 3,000 people, but has only 260 parking spaces. Perfectly located in a loop of the metro, with this own stop, the STCC invites congress participants to reach the campus using public transport. An efficient route-calculation tool allows delegates to choose the most sustainable solution. On site, the participants will find well-designed accesses for pedestrians and cyclists, a car-sharing offer with combustion-powered and electric vehicles, close to 500 parking places for bicycles and a new public bike-sharing station for 20 bikes connected to the Lausanne-Morges network. In front of the entrance, there are full facilities such as shops, restaurants, hotels, medical and dental care services, a pharmacy, newspaper kiosk and pub. Exchange car parks with shuttle services may be organised exceptionally, if necessary.

Underground geothermal pillars

Built on highly unstable land, the STCC rests on 30m deep pillars. EPFL’s Laboratory of Soil Mechanics used the opportunity of the construction to install four geothermic pillars equipped with absorption tubes in which a heat-transmitting fluid circulates, enabling heat exchanges with the ground. The scientists use this lab to study the potential of heating and cooling capacity of these pillars and their deep static deformation.

STCC reception

EPFL ensures that the STCC is operated respecting sustainability in the following manners:

- A measured distribution of low-impact material (paper, promotional items, badges, etc.)

- Exemplary waste recycling (recycling rate of 60 per cent, organic waste to local biogas facility)