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The Swiss healthcare company committed to ridding itself by 2015 of chemicals that harm the Earth's ozone layer or cause global warming. In order to design the most energy-efficient and environmental-friendly solutions new refrigeration systems for plants in Germany, Ireland and the U.S. use only natural refrigerants, mainly ammonia.

Three new big plants using natural refrigerants have been planned and partly realised in the last three years for the healthcare company Roche. Roche's Indianapolis campus in the U.S, the Roche Ireland Ltd plant and a brand new distribution centre in Germany are the first main construction projects of Roche on the way to eliminating traditional refrigerants damaging the environment. As a consequence of the Montreal Protocol on Substances that Deplete the Ozone Layer, the company committed to support the legislation and phase out ozone-depleting substances (ODS) by 2015.

A centralised ammonia chiller for the Indianapolis campus

The existing air conditioners using fluorocarbons at Roche's Indianapolis campus have to go, in favour of an ammonia-based central chiller plant. The 16,000 m² chiller plant building has already been fitted with seven big ammonia chillers that cool water to 42ºC, with the constructions planned to be finished by the end of 2009. The water will be pumped through a pipe system that has feeds to individual buildings on the campus. The plant will keep the company's 2,700 local workers just as cool but in an environmentally friendlier fashion.

The choice for the natural refrigerant requires simply some safety features, such as ammonia sniffers to detect even the smallest leak or metal casings for the chillers. The centralised chiller will not only be environmentally friendlier but also cost-effective by being twice as energy-efficient as using individual units.

Ammonia – one of the most efficient refrigerants for German and Irish plants

Another project that intends to eliminate ODS by replacing the old systems with a centralised ammonia refrigeration system started in 2007 and is partly funded by Sustainable Energy Ireland under the Industrial Best Practice Initiative. With a COP of the old plant measured at approximately 1.6, the COP of the new plant is calculated at 2.9. This increase in efficiency provides substantial energy savings of about 925 MWh/yr, which equate to 575 tonnes of CO₂ savings annually.

For a new logistic centre in the southwest of Germany the healthcare company decided to use a mixture of the natural refrigerants ammonia, propane and CO₂ to cover a wide temperature range from -70°C to +30°C.

About Roche

The Roche group is the world's sixth-largest healthcare company whose principal businesses are pharmaceuticals and diagnostics. It is active in over 150 countries and employs around 62,000 people worldwide.