In this time of environmental awareness, tax credits and substantial utility rebates (up to 50%) for greening commercial buildings one would think that all pre-existing buildings should have been retrofitted with an energy management system (EMS) or a direct digital control (DDC) system by now. In fact, many older buildings have never been retrofitted and some that were originally equipped with early digital or electro-mechanical energy management control systems have fallen into disrepair. These buildings are usually running non-stop creating a negative economic and environmental impact. I would like to share six economic benefits an environmentally responsible approach can achieve by retrofitting or upgrading inadequately controlled buildings to DDC controls.

The benefit most people associate with DDC controls is the anticipated decrease in energy usage. With buildings controlled by conventional thermostats, you may conservatively expect to achieve a reduction of 10% to 15% in energy usage. Even buildings you would not normally suspect to be prime candidates for energy savings with a DDC system could surprise you. Consulting with an experienced controls contractor may help you identify opportunities to maximize energy efficiency and reduce operating costs that may have been previously overlooked. Reducing energy usage can lower your utility bill and reduce your carbon footprint, but energy savings alone is not the only economic benefit you can expect from converting your building to DDC controls.

One surprising economic benefit we encounter is reduced HVAC service calls. A properly equipped DDC system can tell a property manager or a building engineer if a unit is operating properly, thereby eliminating unnecessary service calls. Reducing unnecessary service calls equals reduced maintenance costs even if you are doing all of your own air conditioning work in house.

A DDC control system with a user friendly software package can save significant downstream labor costs compared to programmable thermostats. In a larger building with many air conditioning systems, a simple schedule change for programmable thermostats requires an individual to physically go to each and every thermostat to reprogram them. It is very labor intensive and tedious to visit every thermostat in a large building. Consequently, the building eventually drifts out of control. In contrast, most DDC systems allow a property manager or a building engineer to easily observe and change schedules or temperatures for all of the air conditioning systems in the building directly from a computer. This can save very significant amounts of time and money.

In studies several years ago BOMA and others determined that a comfortable, happy tenant was much more likely to renew their lease than one who had experienced multiple comfort issues. What does it cost in lost revenue and other allowances to replace a tenant who moves out? Would you consider it a substantial economic benefit to be able to reduce the number of tenants who decide not to renew a lease because of comfort complaints? A properly managed DDC system will help you do just that. DDC control systems are capable of maintaining temperatures much more accurately than electro-mechanical controls or programmable thermostats. Most also have software features that can be configured to provide an alarm to a building engineer, or a property manager before the tenant knows there is a problem. Your ability to respond proactively to a problem before the tenant even knows it exists can certainly go a long way toward keeping them comfortable and happy.

Revenue recovery is an exciting potential economic benefit with DDC control systems. Most leases provide for comfortable temperatures during specific hours only, but do not guarantee the same temperatures will be maintained outside of those times. Tracking after hours tenant usage of air conditioning systems and billing it back to the tenant is a very simple way to recover revenue that would normally be lost. User friendly software is available that when integrated into a compatible DDC control system can do that for you. Payback on this portion of a DDC software package can be phenomenal for the building owner while encouraging environmentally responsible use of the air conditioning system by the tenant.

By installing a DDC control system and realizing the economic benefits described above, you will experience yet another economic benefit. Reducing building operating expenses while maintaining or increasing revenue, yields an increase in net operating income. The CAP rate of your building will be improved and its value increased accordingly.

About the author:
Mark Strahan is a 35-year veteran of the HVAC industry and is currently an account manager with Burt-Burnett, Inc., an HVAC mechanical service and digital controls contractor. Mark can be reached with comments or questions at (480) 557-8593 or strahan@burt-burnett.com.