BioPharm: In terms of specific facility operations, can you address the common needs for energy management in biopharmaceutical manufacturing?
Also, what key things should companies look for when planning for these systems?
Lacey: Energy management is becoming increasingly important across the industry given that there is a strong green agenda worldwide
and the need to reduce carbon footprint. There is also a very strong need to reduce cost base, and energy cost is a major
portion of the operation cost of most pharmaceutical plants. Companies fall into a number of categories in terms of how they
manage energy. For example, there are companies who manage energy very well according to national and international standards.
They dedicate resources to energy management, and these resources make a big difference to operating cost. There are other
companies who engage in energy projects and do quite well in terms of saving money, but perhaps, don't manage energy in a
structured way. And then there are those companies who do not address energy issues at all.
Overall, energy must be factored into plant design and construction. It's particularly relevant to those who are looking at
inward investment in new plant construction. New plant construction provides an opportunity to get energy management right.
The problem that the industry faces in designing a plant is that it must comply with cGMPs and must be validated. Requirements
for energy usage reduction can sometimes conflict with cGMPs, for example in relation to air changes, but I am convinced based
on my experience that designers, production teams, quality teams, and engineering teams can work together to deliver an energy
efficient plant that is also GMP compliant.
BioPharm: What other factors are at play with energy systems and cost?
Lacey: There are many opportunities to make gains in terms of the building, such as good insulation and draft-proofing, use of
solar gains, natural lighting, intelligent lighting, compressed air usage, an optimum strategy for HVAC (heating, ventilation,
and air conditioning), and use of alternative energy sources.
HVAC systems are major energy users, due to the requirement to make air changes in rooms and to condition the air. Air changes
represent scope for cost savings. For example, if you have a Grade B room with a national requirement of 20–30 air changes
per hour, the air change rate should be critically reviewed to suit the operation. At building design stage, room sizing (i.e.,
volume) should also be optimized. Thus, the air moved and conditioned can be minimized and so minimize energy usage. Most
HVAC systems in pharma processing applications are "once-through". However, the use of recirculation systems should be adopted
where possible as these are less expensive to run. Finally, room temperature control is key to optimizing energy usage. Room
temperatures should be selected to suit the process and/or occupants.
Lighting is an appreciable proportion of a plant's energy usage. High-frequency fluorescent systems allow for dimmable lighting,
so facilities can use dimmers to control the lighting in a way that it reacts to ambient light level. If a building has natural
light, the fluorescent lighting levels can be dimmed accordingly. Lighting in public areas should react to presence and ambient
natural light. "Intelligent lighting systems" should be considered.
Air compressors represent another area of opportunity for cost savings. Companies should analyze their air usage, and maybe
use two or more smaller compressors rather than a single larger one. They should have variable-speed drives (VSDs) to allow
maximum flexibility of response to demand. Most importantly, plant managers should ensure air leaks are repaired, as leaks
can represent up to 30% of compressed air generation, and contribute significantly to energy wastage. In a medium size plant
of 10,000 square meters, it can cost something like €60,000–70,000 (approximately US$78,000–91,000) per year to run a compressor.
Lastly, it's important to train staff about energy management. People use energy, and if they are taught good habits (e.g.,
turning off lights and monitors), then money can be saved.
BioPharm: You mentioned using two smaller air compressors instead of one larger unit. What benefit does this provide?
Lacey: As I mentioned, an air demand analysis needs to be done before that decision is made. Your air compressor supplier can do
this for you. This improves response and "scalability" between air demand and compressor running. One plant I worked with
had a single large compressor supplying the entire factory, and had a fixed-speed drive. The problem with this is that the
motor either runs 100% or is off completely. This means that a large motor has to stop and start in response to changes in
demand and this is not energy-efficient. A smaller unit fitted with a VSD can respond more flexibly. Using two smaller compressors
also means that you have a backup in case one unit fails.