This article describes the role of energy performance benchmarking in the pharmaceutical industry, explains why large variations in building performance exist and how to use benchmarking data to drive meaningful results into a successful energy management program.
You can’t manage what you can’t measure. This axiomatic statement holds true in all aspects of life; it is hard to manage one’s weight without a scale and it’s hard to manage how fast one is traveling without a speedometer. Likewise, it is hard to manage the energy performance of a building without a similar macro-level indicating gauge.
There is no better way to assess the overall performance of a building than to compare it to other buildings similar in form, function, and location. Unfortunately, this is frequently an acutely difficult task to perform in the pharmaceutical sector. While tools for this evaluation do exist, they are not without their limitations as the approach for comparison is sometimes over-generalized. Facility design and layout play a dramatic part in the overall utility consumption of a facility as, unlike in the commercial sector, the majority of the energy consumption in pharmaceutical manufacturing buildings lies within the process itself and the systems that support it. Several examples will be presented to show just how profound the differences in energy consumption can be. This article will describe the role of energy performance benchmarking in the pharmaceutical industry, explain why large variations in building performance exist and how to use benchmarking data to drive meaningful results into a successful energy management program.
Commercial Building Benchmarking
In the commercial building realm, there are extensive resources available that make this data available for all to use. The Commercial Building Energy Consumption Survey (CBECS), managed by the U.S. Energy Information Administration under the Department of Energy (DOE), has collected and analyzed data for many different types of commercial buildings. The CBECS database is the most robust resource currently available, not only from the quantity of buildings in the survey, but from the vast number of ways that the data has been sliced and diced for comparative purposes as well.
The CBECS is a national survey that collects information on the stock of United States commercial buildings including energy related building characteristics, energy consumption, and expenditures. The buildings in the study incorporate all buildings in which at least half of the floor space is used for a purpose that is not residential, industrial, or agricultural. The survey includes building types that might not tradition-ally be considered commercial, such as schools, correctional institutions, and buildings used for religious worship.
The CBECS database has had several setbacks in recent years with the 2007 survey information being thrown out due to insufficient survey methods and the 2011 survey being cancelled due to funding cuts. Fortunately, funding has since been garnered and work on updating the survey for 2012 has recently begun. Regardless of its flaws, the CBECS database remains the best source of reliable information to benchmark the energy performance of a commercial building.
It is upon this premise that the Environmental Protection Agency’s (EPA) Energy Star building performance rating system has been built upon. Using the information in the CBECS database, energy performance indicator tools exist that allow users to input simple statistics regarding building size, type, location, occupancy and overall utility consumption in exchange for a 1-100 percentile rating that benchmarks the performance of the user’s building against similar buildings. Buildings scoring in the 75th percentile or higher are eligible for the Energy Star certification. The tool compares the inputted building criteria to a normalized model to adjust for inconsistencies in form, function, and location based on the CBECS database.
Commercial buildings have a common bond in their primary function in that they are designed primarily to maintain the comfort of the occupants. Lighting and space conditioning (heating, ventilation and air conditioning) energy consumption are relatively similar and vary predictably with only a few variables. Based upon the EIA Annual Energy Outlook 2012, lighting and space conditioning account for 13.6% and 47.3% respectively (60.9% combined) of the total building energy consumption footprint. The remaining consumption is allocated between various plug loads and water heating requirements.
Since the majority of the commercial building energy consumption is dedicated to lighting and environmental comfort systems, the Energy Star tool needs only to prompt the user for a small number of inputs to be able to quickly normalize the subject building to the model and develop a highly reliable energy performance benchmark.
Pharmaceutical Building Benchmarking
Moving out of the commercial building realm into the industrial and manufacturing building classes, a problem arises. In general manufacturing, energy is also consumed to con-duct whatever processes are required to make the product. This consumption frequently goes beyond just powering the production equipment itself; it also encompasses increased base building utility system requirements from additional or more stringent HVAC requirements to greater lighting intensity requirements to additional utilities such as compressed air, vacuum systems, etc. It is this manufacturing energy consumption that is highly visible and difficult to normalize within a benchmarking model. This problem is exacerbated in the pharmaceutical industry due to the need to maintain critical environments for production with respect to temperature, humidity, room pressurization, cleanliness, containment, and other contributing factors. Building HVAC loads are many times greater than the average commercial building to support these processes. As a result, overall building Energy Usage Intensity (EUI) is typically an order of magnitude larger or more. The average recently built (after 2000) commercial office building has an average EUI of 81.4kBtu/sq.ft. (257 kWh/m3). The average pharmaceutical plant has an EUI of 1,210 kBtu/sq.ft. (3,819 kWh/m2). Contributing factors to these relatively higher levels in building HVAC loads compared to general commercial buildings include, but are not limited to, the following:
- Increased airflow quantity requirements
- Increased ventilation requirements
- Increased filtration requirements
- Requirements for tighter environmental controls (temperature and humidity)
The above factors lead to higher energy consumption through increased:
- Cooling loads
- Preheat loads
- Reheat loads
- Fan energy consumption
- Dehumidification/humidification loads
Discussion regarding the qualification and analysis of the causes for increased consumption is a study in itself and is often cumbersome to calculate. For simple comparative purposes however, consider that a standard air handling unit serving an office area is going to condition and supply between two to six Air Changes Per Hour (ACPH) to the space in a variable air volume control strategy. An analogous air handling unit serving an ISO 14644-1:1999 class 8 (EU Grade C in operation) cleanroom in which pharmaceutical product is being manufactured would typically condition and supply between 20 and 35 ACPH to the cleanroom in a constant volume control strategy. This represents approximately a four to six fold increase in HVAC energy expenditure before tighter temperature and relative humidity control requirements, increased outside air requirements, and additional filtration are considered. With the additional energy consumption of the manufacturing systems and processes themselves, it can easily be seen how the overall energy consumption of pharmaceutical facilities becomes far more intensive than their commercial facility counterparts.
Based on the unique nature of the industry and the in-ability of existing tools to effectively gauge the performance of these buildings, the EPA Energy Star program developed a meaningful comparative tool uniquely dedicated to benchmarking energy consumption in the pharmaceutical industry. Led primarily by energy managers from several major drug manufacturers, the Energy Star program began a pharmaceutical industry focus early in 2005. From those initial efforts, the first version of the pharmaceutical industry Energy Performance Indicator (EPI) tool was developed and published at the end of 2008. Last updated in the summer of 2021, the tool seeks to normalize and benchmark facility energy performance of facilities located in the United States across three major categories:
- Bulk Chemical (Active Pharmaceutical Ingredients and Excipients) – areas where both active and inactive ingredients are prepared in bulk form, including mixing, milling and drying of powders, and the mixing of liquids, gels and creams.
- Fill/Finish – all areas used for fill or finish processes or other manufacturing, production or warehousing with climate controlled environments due to product requirements. Fill/Finish includes tableting and encapsulation of powders or liquids, the final packaging of the product and the filling of liquids, gels or creams in their consumer packages.
- Research and Development – laboratory buildings including animal labs, storage space, in process labs, QA labs and pilot plants.
- Other – final category dedicated to any area that does not fall into any of the above main categories.
Since data regarding space allocation in the above categories is not collected in the Census of Manufacturers, data had to be provided directly from participating entities within the program. Similar to the commercial buildings program, the pharmaceutical EPI takes several inputs regarding percentage of facility floor space allocated to the above functions, hours of operation, location, and utility costs and in return will provide a 1 to 100 percentile rating for the facility. This tool also now provides the EPA with a benchmarking tool to grant the Energy Star rating to facilities scoring in the 75th percentile or above, which was not previously possible.
Variations in Benchmark Data
When the EPA initiated discussions about developing a plant level benchmarking tool with pharmaceutical manufacturers, most initial reactions from experts within these companies were skeptical about whether a useful benchmark could be developed. The typical approach for the development of EPIs for other industries is to relate plant input to plant output as expressed as a unit of production. The pharmaceutical EPI does not. It was decided that the value of product shipments would not provide a uniform measure of activity since, as discussed above, while the level of production is not insignificant, much of the energy use in this industry is devoted to environmental control.
Read the rest of the article from Pharmaceutical Engineering.
