All Case Studies

Hotel HVAC - Chicago Illinois
Chiller Optimizer - Hilton Hotel, Palm Springs, California

The Mode Green Solution

  • Can be incorporated into both new construction and retrofit solutions.
  • No wires need to be pulled.
  • The Mode:Green system can reduce overall water and power use by as much as 50%.
  • Our team will work with you to target key cost savings areas, develop a solution, specify it, cost it and implement it.
  • Based on the USGBC LEED program and has proven ROIs based on reduction of monthly utility costs.
  • Basic Mode:Green Systems (Tier One) are very cost effective and have excellent ROIs
  • Accomplished through a simple internet based user interface that allows Mode:Green's servers to track the consumption of power and water based on pre-set parameters and intervene where necessary
  • Works in real-time and offers a simple, yet powerful dashboard display of all consumables being monitored.  
  • Creates a system customized to every clients needs that reduces costs, carbon footprint, and allows real-time analysis of all consumable resources. 
  • Displays the actual power and water consumption of a room, unit, building, or several buildings/ facilities and makes critical adjustments throughout each 24 hour period to optimize cost savings.
  • System communicates with power, water, solar, wind, irrigation, lighting and security systems.
  • Combines to create a unique resource management system.

Chiller Optimizer 

Hilton Hotel

Palm Springs, California

Hilton Palm Springs has been a progressive user of enhanced automation for over two decades, dating back to its first installed energy management system (EMS) in 1984. It has recently upgraded to a third generation EMS to stay current with advancing technology. The new system is linked to programmable thermostats throughout the hotel and is on a pulse meter that monitors real-time energy use through a new energy information system (EIS).

From a centralized computer, the building engineers establish start/stop set points that correspond to occupancy levels in the meeting rooms. For example, at the beginning of each week a building engineer enters the weekly meeting schedule into the system, and the EMS then regulates the HVAC to match occupancy periods. The operator sets a target room temperature, and the system determines and sets the necessary ramp up time needed for the HVAC system to reach a desired set-point. The Hilton compliments this load shedding strategy with a procedure to shift peak energy demand from the ice machines, dishwashers, and in-house laundry to non-peak time periods.

The Hilton has improved its overall HVAC and EMS capability by upgrading two 140-ton chillers with optimizing equipment and by retrofitting all 1⁄4 to 30-horsepower motors with high efficiency motors and installing variable frequency drive evaporator motors in the walk-in coolers.

  • Upgrade energy management system
  • Shift peak loads to non-peaks periods
  • Install advanced chiller optimizer

Benefits:

Hilton’s energy management strategies have helped cut the overall average building demand (kW) by 48 percent compared to pre-retrofit levels. The Hilton can now optimize comfort levels for building occupants while reducing energy costs. The EMS has streamlined maintenance operations by providing a centralized location to adjust room environments. Prior to the upgraded EMS, building engineers would have to physically monitor several meeting rooms at once, often interrupting ongoing meetings. Now they can monitor and control all room temperatures through a convenient centralized computer—freeing up staff time and reducing comfort complaints from meeting participants.

The energy trending data from the EIS—particularly kW, kWh, and cost data—has become an important tool for Hilton’s building engineers to track and analyze building performance. They have used this data to justify new energy improvements such as chiller optimization, using solar water heaters for the 110,000 gallon swimming pools and installing two 140 kW cogeneration units with a 50-ton absorption chiller to generate power during peak period. The chiller optimizer alone saves $36,000 annually with improved temperature set points based on outside air temperature and return water temperature.

  • Centralized HVAC control
  • Energy and cost savings
  • Real-time and archived energy data

Technical Information:

Hilton Palm Springs uses a Honeywell Light Commercial Building Solution (LCBS) energy management system to integrate all its heating, ventilation, and air conditioning equipment. The LCBS is combined with the Honeywell Lon Spec configuration software, which allows operators to control set points and monitor real-time and archived energy trends. The Lon Spec software communicates with Honeywell’s T7300 Communicating Commercial Programmable Thermostat as part of the building’s open direct digital control (DDC) automation system. The DDC’s are a networked system of microprocessor-based controllers connected to devices that monitor and control the building’s HVAC equipment. Hilton Palm Springs takes advantage of three primary start/stop functions of the system to reduce its energy demand. First, the EMS is programmed to start up the HVAC system one hour prior to a meeting’s start time in order to reach a desired temperature level. Conversely, the system ramps down the HVAC as the meetings are scheduled to end. Secondly, the system can tell if the one-hour start up time will be insufficient (based on indoor and outdoor temperatures) and will pre-condition the space to reach the desired set point before the meeting starts. This function acts as a safety net for the hotel and guards against comfort complaints. The third function allows the operator to set upper and lower temperature boundaries for different building zones. This keeps the hotel within a comfortable temperature band and protects the system against large localized demands. The Hilton installed a Millennium Series Chiller Optimizer with ELECTRA software on their two 140-ton chillers to add further efficiency performance to the HVAC system. The Optimizer has achieved 37 percent electricity savings on the chillers by fine tuning energy levels based on 5-minute interval testing of outside temperature, chilled water supply, and return water temperature.