Energy Management Strategies for HVAC

June 7, 2014

When new facilities are being built, building owners have the opportunity to purchase and install the latest state-of-the-art HVAC equipment, complete with features and other technologies that are designed to keep energy costs to a minimum.

However, retrofitting existing buildings with the latest HVAC systems is not always an option, given the capital costs associated with such investments. As a result, facilities managers are often forced to look around for other strategies and technologies to better manage the energy associated with thermal needs. Fortunately, there are numerous options.

“One challenge for facilities managers and engineers is having to deal with inefficient equipment,” says Kevin Callahan, product marketing manager for Alerton, a business unit of Honeywell. “Depending on the age of the facility, equipment that has been manufactured more than 10 years ago probably doesn’t operate as efficiently as the equipment that is being manufactured today.”

This not only adds to the energy costs associated with the facility, but the additional costs associated with maintaining and repairing the gear, as well as trying to get it to continue to operate at its peak performance. However, it can be a huge capital expense cost to replace.

Years ago, according to Callahan, energy management meant scheduling, responding to alarms, and looking at trend logs to find out where problems existed. “Since that time, technology has provided the opportunity to analytically look at energy consumption and actually turn things off,” he says.

Alerton’s software is able to do all of that: provide a view of what is happening in the building, do scheduling, respond to alarms, and look at log data. “All building automation systems [BAS] do that,” says Callahan. “So, one thing we are focusing on is a human-centered design aspect of our software-how users interact with the software, and how the users are affected by the interface-making it easy to reduce the need for extensive training on the operation of the BAS.”

Alerton focuses on the workflow and reduces the number of steps it takes to do something in the system. In early 2014, for example, Alerton introduced the Ascent Building Management System, which combines software, wall sensors, and a control module in such a way that it provides easier monitoring and control of HVAC and other building systems.

One feature of Alerton’s products is the ability to monitor as many meters as desired, and individually turn things off based on one or more of the meters. “When we talk with customers, the biggest frustration they have relates to what they can and cannot turn off,” says Callahan. “For example, you can’t turn lights or fans off when people are in the building.”

As a result, it is important to create an energy management schema in the building. The first step is to profile the building: When does it use energy, and when does it not? What are the things that cause it to use energy?

“Then, once you determine a value where you want to reduce consumption, you can look at what you can turn off without affecting the environment in the building,” adds Callahan.

Older buildings weren’t built to be able to do this, but these days, architects and engineers design buildings with energy management in mind, making it easier to introduce technology designed to reduce energy.

“When I talk with customers and ask them how often they get on the system to monitor their buildings, some of them say every day,” says Callahan. “Others say once a week. They figure as long as it’s working, there is no need to look at it.”

However, according to Callahan, facilities managers should use the software to its full capabilities, maximizing the capabilities in terms of scheduling, alarms, etc. “Work with your control contractor to have the software give you good information, and then use it, and make it actionable,” he says. For example, the software tells how many hours of run-time is on a fan, which will alert whether it may be time to go in and service it.

When building a new facility, Callahan recommends that the facilities manager try to become part of the design process, providing input on what makes sense. At the very least, the manager should get involved as the project is closing out, to see how things are configured. “The more the facilities manager knows about the BAS and how it is designed, the more comfort he will have in using it,” he says.

Photo: iStock/kjorgen
Over 3,600 thermostats from Network Thermostat are installed at the Burj Khalifa in Dubai, the world’s tallest building.

The future of this technology? According to Callahan, nothing has really happened in the industry since the early 1980s. “Back then, computers, with their microprocessor-based controls, replaced pneumatics as the commercial building system, providing the ability to measure, sense, and control anything in the building with just a pair of wires,” he says. “Some people say the Internet has been a big change. All that has done is make sure that the facilities manager can’t go on vacation. He ends up being connected all the time.”

Callahan believes that the next big thing will be that the building will think for itself. The BAS will be able to tell the operator, “I have noticed this pattern or trend. Here are some things that can be done to increase comfort or decrease energy consumption.” The operator can then decide whether to do this or not.

“However, eventually the operator will gradually begin to feel comfortable, to the point where he will allow the BAS to do this on its own,” says Callahan.

In the meantime, as Callahan sees it, wireless is going to become more popular, especially in older buildings, where it is difficult to open up walls or get into the structure of the building. “Wireless will really change the industry,” he says. “In fact, we will be coming out with a wireless product line this year. Facilities managers will be able to place wireless sensors anywhere in the buildings and gather data at one central location.”

One satisfied customer of Alerton technology is Time Warner HBO (New York City). “The ease of use was one of the things that first attracted me to Alerton,” says David Ewing, manager, facilities engineering. “Then, what really sold me was that we put Alerton on a small job, and they staffed it with engineers and technicians, implemented all of the processes and procedures that we required, met our timeline, and turned the job over to us complete.”

Facilities engineers at Time Warner HBO are always looking for ways to reduce kilowatt consumption. “At one point, we did a project that ended up using a little bit too much kilowatts,” says Ewing. “However, we were able to use Alerton’s system to trend our kilowatt consumption. As a result of the analysis, we are now working on a project that will involve redistributing power to reduce the kilowatt load.”

According to Jason Tienor, CEO of Telkonet, one challenge for facilities managers is that, when a new piece of equipment is implemented, it only operates at optimum for a specific period of time without attention, whether that attention be maintenance, repair, or augmenting the equipment. “It is important to know what that timeframe is for each piece of equipment, such as when you need to change the filters, when you need to check the belts, et cetera,” he says.

However, this monitoring and action comes at a price. A significant amount of time and work are required to perform these tasks, to keep the equipment operating at optimum efficiency.

Tienor notes that some technologies, such as variable frequency drive motors, are designed to increase the efficiency of original equipment. However, if the units are operating at all times, and they are not needed for that amount of time, they are still consuming energy.

“By adding our technology, the system only operates when the user or guest is in the room, saving energy that would be consumed when the unit is operating and no one is in the room,” he says. “This is very useful for the hospitality industry, where statistics show that any given room is usually only occupied about 30% of the time.”

Telkonet’s platform, called EcoSmart, is comprised of three components: software-as-service in the cloud (so users can log into the system from anywhere in the world and manage efficiencies); the products, or hardware components, that are installed in the facility that provide the reading on energy consumption and make changes to the efficiency measures and implement different types of integration with other controls (including either wired or wireless thermostats); and the service that the company provides to make sure the building is operating optimally. The company’s customer base is primarily hospitality, military, education, healthcare, and general commercial.

When implementing Telkonet technology, Tienor recommends that building owners monitor usage to see where efficiencies can be increased, and where maintenance and attention are needed in the building. “They can do this by looking at patterns and trends on the software, so they can then send engineers to the rooms where maintenance or repair need to be done,” he says.

As regards the future, Telkonet is now working with customers to help them understand demand response, and what the implications, opportunities, and benefits are for them with this technology.

One satisfied Telkonet customer is New York University (NYU). Faced with rising energy costs and new commitments to become a model for campus energy efficiency, NYU required an energy management system (EMS) that would minimize energy usage and provide ease-of-use for the maintenance department. With 96.5% of the university’s energy being used for heating and cooling, the focus was obviously in this area.

Several different systems heat and cool each building, including Packaged Terminal Air Conditioners, fan coil systems, and water source heat pumps. As a result, retrofitting the heating and cooling equipment required an adaptable solution.

NYU ended up selecting technology from Telkonet, including EcoSmart, SmartEnergy, Recovery Time, and EcoCentral Virtual Engineer. “The adaptability of both EcoSmart and SmartEnergy proved invaluable when it came to retrofitting multiple buildings with significantly different heating and cooling systems,” says Dianne Anderson, sustainable resources manager for NYU.

In addition, with the installation of a networked EMS, facilities managers gained access to EcoCentral Virtual Engineer, which provides them with the ability to view energy usage, remotely determine a room’s occupancy status, and change temperature settings with the click of a mouse. “Now we have an intelligent system in place that maintains student’s preferred temperature when they’re in the room, yet within our own specified range,” says Anderson. “The centralized monitoring software helps maintenance staff react to problems, often before students know there’s an issue, saving everyone time and improving student comfort.”

As a result of the Telkonet installations, NYU is saving approximately $728,000 a year.

Network Thermostat
“Our customers have been telling us for years that managing multiple pieces of equipment remotely, either from outside the facility, or from a different location within the facility, is a major challenge,” says Jerry Drew, president and founder of Network Thermostat.

One component of management involves updating schedules and operational parameters of the thermostat and locking the thermostat down, so that unauthorized individuals can’t change the settings. “The biggest challenge here is making sure that HVAC systems go into set-back mode when they are not supposed to be running,” says Drew. “In other words, set it back or turn it off when you’re not there.” Another component is being able to receive notifications when things are not operating properly.

Network Thermostat offers a wide range of communicating thermostats-18 different platforms with four different communication technologies. Two of these are wired (one proprietary and one ethernet), and two are wireless (a mesh network wireless and Wi-Fi). Almost all of the company’s customers are commercial. “Our thermostats can be used in facilities of any size, from the smallest to the largest,” says Drew. In fact, the company has over 3,600 thermostats in the Burj Khalifa in Dubai, which is the tallest man-made structure in the world.

As Drew sees it, the key to success in using the company’s technology is to use the various user restriction and lockout mechanisms in order to maintain control. The methods to update the thermostats are very simple. And, of course, when facilities managers receive e-mails or text messages that something is out of the ordinary with the HVAC unit, it is important to investigate.

Drew’s view of the future is similar to that of Telkonet’s Teinor-the growth of demand response. “We are doing a lot of trials with automated demand response,” he says. “We have technology in all of our thermostats that allows our commercial customers to integrate these with their utilities’ demand-response programs.”

One satisfied Network Thermostat customer is the Oral Roberts University (ORU)-CityPlex Towers (Tulsa, OK). “In 2010, I was working for a different company and was looking for something on the market related to network thermostats,” says David King, director of energy management. “I came across two companies, including Network Thermostat. I contacted both companies, but ended up selecting Network Thermostat. I was very impressed with the amount of time they spent explaining their product.”

Later that year, King came to work for ORU-CityPlex Towers, which was built in the mid-1980s. The facility has three towers: a 60-story, a 30-story, and a 20-story. There are over 350 constant-volume air handlers in the three towers and the base, which comprises 2.4 million square feet. “When I arrived, I was surprised to find that 210 of the 350 units were running 24 hours a day, seven days a week,” he says. “There was no energy management system at all.”

Knowing that he wouldn’t be able to get a multi-million dollar capital budget to install an EMS, King started working out of the expense budget to purchase thermostats from Network Thermostat and installing one at each air handler, so that he could put a scheduler on them and control them, being able to turn them on and off remotely.

“They were fairly inexpensive compared to the cost of a full-blown energy management system,” he says.

The installations ended up working so well that King eventually decided to put variable frequency drives on the air handlers, and then began to control the speeds in each unit using the setpoints off of the thermostats. To date, he has 193 of the air handlers online.

Airius LLC
As noted so far, new technology is an effective way to manage HVAC-related energy costs relatively inexpensively. However, there is still something to be said for some basic solutions-including ceiling fans.

“Energy prices continue to rise, so customers are looking for ways to improve energy efficiency, such as radiant heat, more efficient rooftop units, and variable frequency drives,” says Taylor Horowitz, inside sales/marketing for Airius LLC.

However, challenges are even greater in high-ceiling facilities, which need to find solutions that can keep the area comfortable without having to over-run the units, because of the air stratification. “This can lead to short-cycling, or the heat ending up being distributed primarily to the ceiling level,” says Horowitz.

Airius’s fans are designed to drive the warm air from the ceiling area straight down to the floor, where the people and thermostats are, and balance the temperature. “Instead of having a temperature differential of ten degrees or so between the ceiling and the floor, our fans can bring that to within one degree,” says Horowitz. This helps keep the thermostats satisfied longer and keeps the HVAC systems from running as often, because they are maintaining equilibrium, rather than trying to offset a constantly changing temperature gradient.

The fans are relatively small compared to everything else on the market, according to Horowitz. They can work in facilities with ceilings anywhere from 8- to 100-plus-feet high. One of the energy efficiency features of the fans is that they can operate at variable speeds.

The fans also help on the cooling side. “It is much easier for the HVAC system to maintain equilibrium by keeping it 65 degrees on the floor and 67 on the ceiling, than keeping it 65 degrees on the floor when it is 85 degrees on the ceiling,” says Horowitz.

The key to success in using these fans, according to Horowitz, is to make sure that they are installed such that they have a clear path to the floor and that they are evenly spaced across the ceiling.

Since the fans improve efficiency so much, it can be a lot less expensive to install them as part of a retrofit than to replace a whole HVAC system.

One satisfied customer is Gallery Solaro (Quincy, IL). When art gallery owner Liz Solaro opened her business in a building that was built in 1857-with high, exposed ceilings; brick and stone walls; and large windows-she knew the building would attract customers because of its appearance. However, she also knew that keeping the building comfortable for daytime visitors, as well as for people attending dinners and weddings in the evenings and on weekends, would be a challenge, both in the chilly winter months, and in the hot and humid summer months.

Solaro’s first attempt to manage temperatures was to run four or five propane heaters for several hours in advance of winter events, in addition to the gas furnace, which was running almost non-stop. Still, the lower level of the building would remain cold. Yet, when Solaro would walk along the upper mezzanine, the temperature would sometimes be in the 80s. Solaro realized things had to change when she received a $2,000 heating bill in January 2012.

Solaro then installed four Airius Air Pear Thermal Equalizer fans on the ceiling. “Airius solved a very difficult problem for us,” she says. Now the gas furnace runs as little as 20% of the time. And, at some events, guests even feel comfortable taking off their jackets…even on the coldest days.
About the Author

William Atkinson

William Atkinson specializes in topics related to utilities and infrastructure.

Photo 39297166 © Mike2focus |
Photo 140820417 © Susanne Fritzsche |
Microplastics that were fragmented from larger plastics are called secondary microplastics; they are known as primary microplastics if they originate from small size produced industrial beads, care products or textile fibers.
Photo 43114609 © Joshua Gagnon |
Dreamstime Xxl 43114609