FC 135A STEP TOWARD GREEN NEPHROLOGY: APPLYING THE PASSIVE HOUSE CONCEPT TO THE CONSTRUCTION OF DIALYSIS FACILITIES
Authors: Mariat Christophe , Rey Jocelyne , Olivier Annie , Jullien Perrine 
Published: May 2021

Abstract

Background and Aims
The environmental impact of dialysis is now being largely recognized. It requires from the nephrology community to actively explore novel environmentally responsible health-care practices. Among them, conception of energy-efficient facilities may be an important prerequisite for improving the environmental impact of dialysis. The Passive House concept is an internationally recognised, performance-based energy standard in construction which so far has been rarely applied to medical facilities and never to dialysis centres. We report our experience with the first passive-house certified dialysis facility in Europe.

Method
The Passive House concept is a sustainable construction standard for nearly zero energy buildings (the Resolution of the European Parliament of 31/01/2008 has called for its implementation by all member states by 2021). Principles and design tools of the Passive House concept are freely available for all architects. The concept combines a particularly high level of insulation with a specific system of ventilation. Geothermal energy and energy from inside the building such as the body heat from the residents or solar heat entering the building are the main energy sources. Passive House buildings allow for heating and cooling related energy savings of up to 90% compared with typical building stock and over 75% compared with average new buildings.

Results
The François Berthoux Center (www.artic42.fr) is a 4 400 m2 dialysis facility operated by 40 health care agents and providing care to 135 patients. It was designed following the Passive-House standard, applied for the first time to such a medical building. Several adjustments specific to the dialysis activity were necessary. The most unexpected aspect was the importance of hemodialysis machines as an energy source. Thorough thermal evaluation showed that the heat provided by different type of hemodialysis machines was systematically superior to the energy mandatory during the coldest day of the year (&gt;10 W/m2). In practice, the center turned out to be fully operational with no external source of heating. The downside was that the geothermal pump system was not sufficient to fully regulate temperatures during the warmest period of the year. Optimal cooling was achieved by the addition of conventional AC systems in the hemodialysis rooms. Overall, as compared to a similar center, energy savings provided by the The François Berthoux Center were substantially less than what is expected from a conventional Passive House building but were over 50%. The extra-cost of the construction was estimated to 3 to 5%.

Conclusion
In conclusion, the concept of eco-friendly building should extend to dialysis facilities. Application of the Passive House Standard in the context of hemodialysis requires to take into account some specificities that can impact the global environmental performance of the building. However, the net result is clearly in favor of such a construction, which is both affordable and sustainable.