Design in a Time of Uncertainty
By Rives Taylor, Principal, Global Resilience Research Lead
The following text was written by HARC's Gavin Dillingham and originally posted to Houston City Energy Project's Blog. For more information on the the Houston City Energy Project, please visit them at www.houstoncityenergyproject.org.
An increasing number of cities and states are implementing policies that promote the benchmarking of public and private facilities. The expectation is that with greater benchmarking comes a greater likelihood for a building owner to invest in energy efficiency upgrades.
Although benchmarking is a very important first step to understanding a building’s energy consumption it should not be done in isolation. The benchmarking process will lead to the best outcomes when coupled with strategic energy management (SEM).
SEM is a comprehensive set of policies, programs and strategies that drives organization decision making involving building operations, maintenance and procurement. Without SEM, it is very difficult to take full advantage of the information energy benchmarking provides. There are a multitude of ways to develop an SEM program, but these key components should be kept in mind.
- Data - For an organization to develop an SEM, it must begin by collecting at least two years of utility data. This data is required for the benchmarking, and also provides the initial information that will be needed to conduct building assessments and audits. Required data also includes building characteristics, which would be operating hours, number of employees, HVAC systems, etc.
Once the data is developed, a building can create metrics. The most common being energy per square foot. This is typically seen as kBtu/square foot. It is also possible to have energy cost per square foot or energy cost per employee. The most common is the kBtu/square foot. A great, free place to compare your building with others is the Department of Energy’s Building Performance Database.
- Energy Management Policy - The energy management policy is the guidebook for a building. The basic components of the energy management policy would include temperature set-points (thermostat settings) to be followed, equipment operating hours and equipment efficiency standards. The equipment efficiency standards determines the efficiency requirements of HVAC and other mechanical equipment for the building, as well as appliances, i.e. computers, copiers, coffee makers, etc. that can be purchased. Speaking of coffee makers, the energy management policy, would also establish what can be plugged in at the office. It is found that in many cases there is appliance creep in buildings, where every office has a mini-fridge and a space heater. This can cause significant energy consumption in a building and can be alleviated with a properly enforced energy management policy.
- Building Operations Strategy – The SEM will also layout the strategy for the many effective low-cost, no cost practices that should be in place at any efficiently operating facility. The low-cost, no cost practices would include a schedule for preventative maintenance, particularly filter changes; retro-commissioning of a buildings mechanical system, with the expectation of moving to a on-going commissioning process; and regularly scheduled building audits. A detailed audit is helpful at least every 3 to 5 years. All of these measures together would result improved operation of the facility over a sustained period.
-Capital Improvement Plan – Finally, an SEM would include a capital improvement plan. This includes a comprehensive list of all major mechanical equipment in the building and the equipment specifications and age. The SEM would identify an equipment replacement time-line that would allow for a pro-active replacement of aging, inefficient equipment in a cost effective manner.
The outcome of the comprehensive SEM is not only a highly optimized building that saves the facility owner money, but also a more comfortable, healthy building that will have lower absenteeism and higher employee productivity.