Air energy meters in air conditioning systems at Merck

Author: Dipl.-Wirtsch.-Ing. (TU) Jens Amberg, CEO Luftmeister GmbH

Fréderic Yvorel is responsible for energy efficiency at the French Martillac plant of the Darmstadt-based pharmaceutical group Merck. This high-tech site, also known as “Merck Biodevelopment”, develops biotechnological manufacturing processes at the highest level. Numerous clean rooms ensure suitable conditions.

From Mr. Yvorel's point of view, most of the media are “energetically in the green area”. For years, however, the high energy costs and costs associated with air conditioning technology have been causing him headaches.

One knows this from the cleanroom environment: The focus is on the availability of the system and GMP conformity. Then “nothing comes for a long time”, and then, if necessary, one also takes care of energy consumption and operating costs.

With the Luftmeister air energy meter, Merck has finally found a suitable solution. The cleanroom air conditioning system is continuously analyzed for energy efficiency. For this purpose, the mass flow (e.g. the main supply air of an air conditioning system) is measured at any time and the enthalpy is measured before / after each relevant treatment stage. The enthalpy (kWh heat per kg air) shows the “heat density” - multiplied by the mass flow (kg air per time unit), the result is the thermal output (in kW) and (added together) the thermal energy (in kWh).

What is the benefit of this effort? Mr. Yvorel puts four useful points in the foreground:

  1. The Luftmeister measuring system discovers so-called “energy destruction” (cooling works against heating or heat recovery). The systematic elimination of these “efficiency killers” on the MSR side is an important contribution to energy efficiency.
  2. the efficiency of each treatment stage (“what does the heat recovery system actually achieve?”) becomes transparent and can often also be optimised in terms of control technology.
  3. monitoring of the air delivery is available at all times: Which volume flow, which temperature, which humidity was delivered to the cleanroom?
  4. in case of a deviation (too low temperature, wrong volume flow etc.) the Luftmeister system helps to find the faulty treatment stage faster.