Are you monitoring your facility’s plug loads?
The Department of Energy forecasts that overall energy consumption by commercial buildings will increase 24% by 2030, but plug and process loads (PPLs) will increase 49%, twice the overall rate. Currently, PPLs represent 33% of energy use in commercial buildings, making them a significant factor in any whole-building conservation program.
To reduce your facility’s PPL, you can work through the 10 steps of a quick-start guide, Assessing and Reducing Plug and Process Loads in Office Buildings, prepared by the Department of Energy’s National Renewable Energy Laboratory (NREL). Applying the principles in the guide allowed NREL to reduce plug loads by 43% in some of its offices. With a utility rate of $0.06/kWh and a decrease of 1,290,000 kWh/year, NREL saves $58,000 annually from the plug load effort.
Step 1: Identify a PPL champion
This person should understand basic energy efficiency practices and be willing to critically evaluate and influence building operations, policies, and procurement. The champion ensures that all decision makers are on the same page and that they understand relationships between systems, such as the impact of heat-generating plug loads on building cooling loads.
Step 2: Institutionalize PPL measures
Refer to ENERGY STAR guidelines to implement energy-conserving policies and procurement measures. The energy champion needs to work with the decision makers who can institutionalize practices based on PPL efficiency measures.
Step 3: Benchmark current equipment and operations
The benchmarking process typically involves a walkthrough to identify PPLs, a metering plan to quantify energy use and power meters to measure and log loads over a week.
Step 4: Develop a business case
To get buy-in from all parties, the champion should develop a business case that justifies the PPL reduction program. In addition to energy costs savings, the business case may address the maintenance and consumables savings from centralized multifunction machines (printers, faxes, copiers).
Step 5: Identify occupants’ true needs
The champion should identify occupants’ true needs for their business functions and seek to eliminate unnecessary and personal equipment in favor of shared, centralized equipment.
Step 6: Identify efficient equipment
Research ENERGY STAR and EPEAT databases to find ratings of energy-efficient equipment. Non-rated equipment should be researched by the champion to find the best options. Beware of parasitic loads, i.e. power draw when equipment is idle and not performing work.
Step 7: Turn it all off
Office buildings are unoccupied for two-thirds of the year. A key part of any conservation program is ensuring that energy consumption is minimized during non-business hours.
Step 8: Address unique loads
Some equipment in your facility may be managed directly by others, such as outside vendors or contractors who operate food service areas or on-site ATMs. Nevertheless, the building owner probably pays the energy cost. Work with outside firms so they use energy-efficient equipment and practices.
Step 9: Promote occupant awareness
The importance of the occupants’ role in conservation cannot be overstated. Be sure to make them aware of efficiency measures and best practices. NREL designed a sticker to remind employees to turn off unused equipment.
Step 10: Have design teams address loads
For new construction and retrofit projects, ensure that your design team looks for PPL decreases. The champion should work with designers to increase space efficiency so that the ratio of occupants and equipment to space is maximized. The design team can also build controls into outlets in workstations and common areas, including switches, vacancy sensors, and timed disconnects. PPL controls can also be integrated into the building management system.
