Beyond Control

Energy management systems incorporate more functions

by Lyda Durango

When energy management systems (EMS) made their appearance in the nineteenth century they were the answer to the need to control temperature in physical spaces.

Two centuries later, EMS has become the answer to more complex and changing needs. One of them is the result of a direct interaction with the environment. Natural light sensors and flexible recovery times according to outside temperature are some of the latest advances in energy management systems.

This, added to the fact that they have evolved into building management systems, BMS, for its acronym in English, makes these solutions a guest of honor for the efficient operation of the hotel.

Lighting, in the shade
However, its permanent transformation has allowed them to be improved to control every part of the hotel's equipment including pumps, valves, fans, compressors and even lighting controls; energy management systems account for a large vacuum.

These modern, state-of-the-art systems continue to be underestimated and underutilized. Options such as lighting control have been relegated to secondary places amid concerns about controlling the expense generated by air conditioning, ventilation and heating. The reason is that the latter constitute the largest uncontrolled operating expenses of a hotel, representing even more than 30%.

Although according to information from the International Energy Agency, lighting consumes 19% of all electricity in the world, Latin American hotels are still focused on other types of savings. "I'm surprised by this," says Héctor Morazán, international sales manager at Litetouch Internacional. "If it's not that important, why do they care about installing compact fluorescent lights?" he asks.

Perhaps the answer lies in the ignorance that architects have of solutions such as lighting controls and their wide benefits that exceed the creation of environments. "A lighting control system allows you to double the life of the bulb," says Mr. Morazán. "The bulbs are not used 100%, only 90% or 85%  and there is a saving in labor and energy expenditure," Explains.

Until now, these types of solutions have been classified as architectural solutions, rather than saving. But the truth is that lighting controls have a huge impact on saving and controlling energy in spaces like convention centers, lobbies, restaurants, and all kinds of public spaces. "The question about the need for this type of solutions has to be asked by the architect when the hotel is under construction," recommends Morazán. "But the main question he has to ask is which spaces are for entertainment use and which are for architectural use, a single solution cannot be efficient with two different uses," he adds.

Integration with the outside environment thanks to the latest developments in natural sensing further enhances the energy conservation benefits of lighting controls. "If the area where the natural light sensor is installed is receiving enough sunlight to keep the ambient light at the desired levels, this natural light conservation kit will reduce the amount of artificial light in the area, lowering or turning off the controlled loads," explains Morazán.

Rooms, under control
Hotel rooms continue to be the area with the highest energy expenditure and greatest attention, but at the same time the one that continues to present the most challenges.  Where temperature, lighting and security come together to make the guest feel good, comfort cannot be put at stake by saving some kw/h. The latest advances in EMS are aiming to ensure that comfort.

While a few years ago these systems could not be activated while the guest was sleeping, the new systems have taken care to fill this deficiency with wireless radio frequency sensors that allow monitoring when a guest is in the room. Still, the biggest challenge continues to present itself when the guest leaves the hotel room. "Most guests are out 60% of the time, which leaves a lot of time for bad spending," says Ana María Huertas, sales director for North America at Energy Eye, a company that offers a wireless energy management system based on RFID sensors.

The wireless systems currently used for energy control can be of two types. The first consists of a wireless system inside the room but integrated to a central point to send information via cable. The other is an independent system within the room, wireless and individually controlled. The independent system offered by this company has the advantage that being wireless makes its integration very simple and when communicating by radio frequency is not limited by corners or corridors.

"It is a way to reduce electrical expenses in the rooms without making the guest uncomfortable," explains Mrs. Huertas. "Usually these types of systems when they are not wireless require that in the installation time the rooms are taken out of service," he adds. "Our system allows that without bothering the guest the hotel does not have to waste electricity," he says.

Power control, networked
Active monitoring of units that represent the highest energy expenditure is one of the ways in which the management and administration of buildings ensures savings in both costs and carbon dioxide emissions. Smart programmable thermostats, packaged air conditioning controllers (PTAC), occupancy sensors and balcony switches to adjust and maintain the temperature of the rooms are some of the features of the most modern energy systems, that of Smart Systems International, telkonet, is one of them.

Telkonet has based its technology solutions on the possibility of using existing electrical wiring to install broadband and now energy-saving solutions. "Telkonet's iWire System connects all components related to a network using existing electrical wiring in a building to provide connectivity to the energy control customer's page. ", explains Alberto Rivera, international solutions manager at Telkonet.

Also using a unique feature on the market, it guarantees comfort while saving the building costs. "We are the only company in the market that has the concept of Recovery Time, this being a selected time in which the air conditioning (or heating) equipment is able to reset the temperature selected by the guest in the room", Mr. Rivera explains.

This is achieved because the thermostat constantly calculates how low or high it can let the temperature fluctuate in order to ensure that the guest's comfort temperature setting is achieved in the time set by the recovery time, just minutes after the guest has returned to their room. All this based on atmospheric conditions. "Proprietary algorithms that work inside thermostats and controllers allow the hotel manager to program the thermostat recovery time," explains Alberto Rivera.

Automation, hand in hand with savings
The constant evolution of EMS has resulted in the most modern building automation systems. BMS are building management systems in an intelligent network of programmed electronic devices that monitor and control existing systems in a building. The system is centralized for monitoring by software that provides real-time information.  

"Some paradigms about energy saving systems have to do with the high initial cost, the difficulty of operation and the fact that the owners believe they marry the manufacturer," explains Rodolfo Hernández Cerón, director of the Mexican Institute of Smart Buildings. IMEI. Experience has shown that automation solutions allow different manufacturers to be integrated and that the building can continue to grow and update its systems without being tied to a single manufacturer. Alerton is an example of this.
"The secret is the correct integration of the different systems, making use of technology to maximize the use of the necessary resources to achieve it," explains Elsa Yañez Ruiz, distributor manager of Alerton Mexico. Having a measurement standard to be able to monitor and control is essential.

"One of the technological tools our company uses to help its customers save is BACnet, which by definition is a standard data communication protocol for building automation and control networks," explains Ms. Yánez. "The purpose is to standardize communication between the different automation devices that exist in a building, regardless of the manufacturer and allow the exchange of information between them, which means that they can interoperate quickly and easily," he clarifies.

The ANSI/ASHRAE 135 standard that dictates the communication standards so that any company can develop a device that speaks this language, without the need to pay for it, has been translated by this company in this line of controls that proposes the control of lighting in public and outdoor areas, monitoring and management of electrical parameters in all substations, in the emergency plant, in uninterruptible power systems, in electromechanical systems in general and in all electrical devices that consume more than 1,500 watts.

With the use of this type of solutions, the hotel can obtain savings in electricity consumption in the rooms on average of 12%. But what will most please the managers of these buildings is the possibility of the reduction of the cost of corrective maintenance and a substantial increase in the useful life of the equipment; In addition, future growth will not be limited by incorporating technologies that allow the use of data networks.

Conclusion
Traditionally, the operation of energy management systems has been tied to the need for supervision by qualified personnel to achieve the expected savings. When hotels have sought savings it has always been easier to change a lamp than to install a system that in the end will more positively impact the total operation of the hotel. Understanding energy management and control needs before taking corrective actions will be a critical first step. And above all keep in mind that it is not only about saving, it is also about service, communication and comfort.