The target ventilation systems are automatic control systems that integrate natural ventilation control (hereafter "NV") and mechanical ventilation control, including
air-side economizer control (hereafter "EC"), demand control (hereafter "DC"), and heat recovery control (hereafter "HR").
It is well known that dampers in the
air-side economizer cannot fully open (100%) during operation.
In most climates however, the switchover from chiller operation to
air-side economizer mode for data centers should be based on enthalpy controls, not on dry-bulb temperature alone.
In addition to displaying live building performance data, educational demonstrations show how the sustainable features in place at the data center actually work, like how free cooling is used to rely on low outside air temperatures to help chill the building's water, and how an
air-side economizer reduces the facility's energy consumption costs.
Note that for fan systems, during occupied hours, Q is the coil load, including the sensible and latent load of conditioning the ventilation air with credit for any
air-side economizer capacity at prevailing return-air and outdoor-air conditions.
Even if your facilities are in a warmer climate, you still have options for savings with an
air-side economizer, says ENERGY STAR: "Because data centers must be cooled 24/7, 365 days per year,
air-side economizers may even make sense in hot climates, where they can take advantage of cooler evening or winter air temperatures."
Two basic approaches that accomplish this are
air-side economizer cycles and water-side free cooling.
(4.) ASHRAE Guideline 16-2003, Selecting Outdoor, Return, and Relief Dampers for
Air-Side Economizer Systems.
"One example would be to identify when an
air-side economizer might not be working in the right weather conditions.
Therefore, the recommended approach of using an outdoor air humidity ratio obtained through the internet can significantly improve
air-side economizer operations.
In West Jordan, Utah, humidification is needed for more than 78% of the hours in a year when outdoor dew-point temperature is below the current minimum acceptable dew-point temperature of 41.9[degrees]F (5.5[degrees]C) as shown in Table 2, which also shows a quick comparison of number of hours when free cooling is available with conventional
air-side economizer as well as with the installed cooling system.
Get your utility costs under control by adding an
air-side economizer. This device draws in outside air as a form of free cooling.
