For many commercial building owners, energy cost reduction programs bring to mind costly projects like window replacements and mechanical system upgrades. However, these tangible items aren't always the most cost effective means to energy cost savings.
Often times, lower-hanging fruit pays bigger dividends for those who take the time to consider the route less traveled. An energy audit is the best way to determine no- and low-cost opportunities for these improvements in building performance.
Beginners' energy audit
While there are various types of audits, an initial walk-through audit (often called, ASHRAE Level 1) begins with a review of 12-18 months of utility history where performance is compared with the intent for the building and peer facilities, adjusting for weather, occupancy levels and hours of operation. This identifies energy usage anomalies that are clues for further investigation. Beyond this initial step, the audit includes a site visit, interviews with facility staff and observation of all energy loads and equipment.
This entry-level audit frequently leads to recommendations that are relatively simple and immediately affordable. For example, common low- and no-cost recommendations commercial building owners-or even leasees-should consider before expensive fixes are lighting, HVAC controls and plug loads. Combined, these represent 85 percent of a building's energy usage.
Lighting systems represent up to 40 percent of a building's energy consumption, making it one of the biggest targets for energy cost savings. While energy efficient lighting is important, turning lights off when not in use plays a large role. Though only mildly effective, the lowest cost remedy is to establish policies to turn lights off when leaving, whether it's for the evening or simply for a meeting in the conference room. A more reliable solution is to retrofit wall switches in offices with occupancy sensors.
HVAC systems typically represent 25 percent of an office building's energy use. Just like homes with programmable thermostats, many commercial office facilities have the capability to "turn-down" equipment after business hours, which has an immediate effect on energy consumption.
In buildings with multiple tenants, the equipment schedules should reflect the operating hours listed in lease agreements. Check schedules periodically and make adjustments based on changes in operating hours and building vacancy.
Energy costs from space heaters, desk fans and computers left on overnight and on weekends can add up quickly. In fact, plug loads typically make up 20 percent of a building's energy use. For space heaters and fans, the solution is to identify and address the root causes-make adjustments to thermostat settings and address heat gain from windows with direct-sunlight. Purchasing plug strips with occupancy sensors built-in can help as well but there is no replacement for occupant engagement and education.
Because the early years of a building's life can be the most critical for long-term energy management, greenSTUDIO often monitors utility trends for the first two to three years for new construction projects. For existing buildings, conducting an energy audit at least every five years is recommended to stay ahead of potential operating issues and unpredicted increases in energy consumption.
While these three areas are common suspects, the only true way to make effective changes is to conduct an audit and learn where energy is going. You can start your search for energy auditors by searching EnergyRightPartners.com.