Advice provided by: Sarah Gudeman, LEED AP, EIT, Morrissey Engineering, Inc.

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Sompoche asks: Do we need to include the process equipment load such as process machine, spot cooling in the energy simulation? If most of energy consumption of the project come from process energy (around 70%) then the percentage of energy reduction may be too difficult to achieve.

Answer:Sompoche, what you’re essentially describing is the long standing issue with data centers (and other high-process-load type buildings) being less likely to pursue or achieve LEED certification. You’re correct in the fact that these types of buildings sometimes cannot prove the necessary energy efficiency reduction compared to the baseline building since process loads must remain constant in the two energy models, according to ASHRAE 90.1 Appendix G modeling parameters. The new LEEDv3 rating system requires that to meet prerequisite requirements for Energy and Atmosphere, the project must improve energy performance over its baseline building by at least 10%. Then, the first EAc1 point is awarded for a 12% improvement over the ASHRAE 90.1-2007 baseline building.

So while this issue has been raised to USGBC before and a coalition of data center industry groups has even released a draft of an energy-efficiency standard for data centers (http://hightech.lbl.gov/dc-epc.html) to expand the LEED rating system (February 2009), when the new LEEDv3 rating system reference guide was released, there were only minimal references to data centers, and no additional guidance on the topic has been released as far as I’m aware. Of course your building might not be a data center, but all high-process-load projects fall into this same gray area.

In the LEED BD+C Reference Guide, the only mention of data centers comes in the summary table reprinted and slightly reworded from ASHRAE 90.1 Appendix G under ‘Process Energy’ which states, “Table G-B provides acceptable receptacle power densities per occupancy type, which can be incorporated into building energy models. Other process energy inputs such as elevators, escalators, data center and telecom room computing equipment, refrigeration, process lighting and non-HVAC motors should be modeled based on actual power requirements, and assuming reasonable schedules of operation.”

So at 70%, you’re well over the typical amount of process energy for a building (25%), but you do need to include all of your process energy in both the baseline and proposed energy models. If you determine that you can’t meet the prerequisite 10% energy improvement over baseline, then unfortunately you’re kind of sunk when it comes to LEED BD+C for New Construction. There are, however, other options. ENERGY STAR is expanding their building certification program (anticipated in June) to allow data centers to earn the building ENERGY STAR label, more information on that here: http://www.pcworld.com/article/188658/energy_star_for_data_centers_comin..., but there I go again assuming your building is a data center.

Regardless, ENERGY STAR offers another program for industrial building certification, http://www.energystar.gov/index.cfm?c=industry.bus_industry.

Good luck!