ENERGY EFFICIENT RETROFITS Date
CONTENT High Volume Low Speed Fan HVLS for Conditioned Space Air Handling Units Centrifugal Blower to BLDC EC fan Efficiency improvement of outdoor chillers Shade net for door chillers Evaporative cooing BLDC EC fan for Chiller Condensers Radiant Cooling for precision manufacturing Low Heat load electric and day lighting retrofit solutions
AHU retrofit with Electronically Commutated (EC) Brush Less Direct Current Blowers
Selection of energy efficient model against original blower Supply air Blower in one AHU Duty Point Power consumption Number of Blower per AHU for supply air Measured readings of Existing Supply air blower Proposing EC Fan for Supply air 48229CMH @ 140 pascal 14.51KW One Blower 48229CMH @ 140 pascal 4.0 KW Five fans Return air Blower in one AHU Duty Point Power consumption Number of Blower per AHU for Return air Measured readings of Existing Return air blower Proposing EC Fan for Return air 41339 CMH @ 535 pascal 15.88KW One Blower 41339 CMH @ 535 pascal 10.3 KW Five fans
Sankey analysis on Losses in AHU Fans 4 % Losses in Electrical components like Invertor 4 % Losses Belt transmission 1 % Losses due to Turbulence in casing 8 % Losses in Induction Motor Maintenance (belt change, foundation etc.,)
Comparison of Centrifugal induction motor driven fan Vs Electronically Commuted BLDC motor Backward curve Radial Fan Type of Losses Centrifugal induction motor driven fan Electronically Commuted BLDC motor Backward curve Radial Fan Mechanical Loss Electrical Losses Maintenance 1.Losses due to Turbulence in casing 2.Losses in Belt Transmission 1. Rotor & Stator I2R Loss 2. Flux linkage loss 3. Rotor & Stator core Loss 4. AC to DC to AC conversion loss in VSD 5.Harmonics high 48% 6.EMC Filters and Related losses 1.Maintenance Ex : (belt change, foundation, Maintenance time gets increased etc.,) 1.Zero power transmission loss as directly coupled 2.Minimum Losses due to Backward curved radial design. 1.Zero Rotor I2R Losses. 2.Zero Flux linkage losses. 3.Zero Rotor Core Losses. 4.Only AC to variable DC conversion 5.Harmonis is Less compared to induction motor was 30%. 6.No Filters required 2. Zero maintenance Because No belts,simple in design.
Why BLDC Motor? BLDC uses Permanent Magnet for field excitation Induction motor - Rotor Losses BLDC Fan - Rotor losses
Why BLDC? Electronic Commutation?
Control AC Vs EC Under Speed Control AC IM FAN EC BLDC FAN
SIMULINK simulation of AC vs EC
Harmonic Analyzer report AC vs DC
Conceptual layout of AHU with centrifugal AC blowers
Conceptual layout of AHU with EC BLDC blowers
CFD Analysis AC centrifugal Vs EC BLDC
EC BLDC are quiet Noise Attenuators & High Static req.
Further opportunities due to EC BLDC blower Retrofit
BLDC Vs Conventional Fan Form Factor Comparison Very heavy and bulky fans with more energy losses are replaced with relatively small fans of high efficiency
Comparison of Induction Motor Fan & BLDC Axial Fan Supply air Blower in one AHU Measured readings of old Supply air blower After retrofit with new EC Fan for Supply air Duty Point 48229CMH @ 140 pascal Power consumption 14.51KW No. of Blower per AHU for supply air One Blower 48880 CMH @ 147 pascal 4.0 KW Five fans Return air Blower in one AHU Duty Point Power consumption No. of Blower per AHU for Return air Measured readings of Existing Return air blower After retrofit with EC Fan for Return air 41339 CMH @ 535 pascal 15.88KW One Blower 42052 CMH @ 552 pascal 10.3 KW Five fans
Before and After Energy Comparison
High Volume Low Speed Fan
Energy Efficiency using HVLS How? Wind-chill or windchill, (popularly wind chill factor) is the perceived decrease in air temperature felt by the body on exposed skin due to the flow of air. Moving air over skin like a breeze (high volume low velocity) breaks up the moisture saturated boundary layer surrounding the skin, thus accelerating evaporation to produce a cooling effect Conventionally speed of fan is increased to increase volume High speed fans are Small in size (Less area coverage) & Not energy efficient due high windage losses HVLS sweep area increased to move more air volume at low speed Ideal for human comfort cooling (ATP / HT )
Energy Efficiency using HVLS Literature survey? Reference : Studies by mechanical efficiency experts show that HVLS fans are the most energy efficient air circulating fans available Tetlow, Karin. "HVAC for Large Spaces: The Sustainable Benefits of HVLS Fans". McGraw Hill Construction. "Ceiling Fans and Other Circulating Fans". Energy Efficiency and Renewable Energy. U.S. Department of Energy. Retrieved February 9, 2011.
Energy Efficiency using HVLS Selection?
Radiant Cooling for precision manufacturing
Literature Survey & Success Stories Infosys new goal: digitising the front-end Source : http://www.thehindubusinessline.com/feat ures/smartbuy/tech-news/infosys-newgoal-digitising-thefrontend/article6987033.ece
Literature Survey & Success Stories Innovative Design Concept for the New Bangkok International Airport, NBIA
Literature Survey & Success Stories Innovative Design Concept for the New Bangkok International Airport, NBIA Radiant cooling
How much saving in Radiant Cooling? Less energy required to transport heat transfer medium (water) when compared to conventional HVAC where air is used. To maintain the surface temperature at 18 to 20 deg C. Chilled water supply from the chiller is typically at 16 deg C in radiant cooling when compared to 7 deg C for conventional HVAC. This also leads to additional savings both in terms of chiller efficiency and less losses in transport
How Radiant Cooling along with conventional cooling? The Radiant Cooling System is designed in a way to circulate the chilled water at 16 to 20 deg C. It will have Aluminium panels with copper pipes in which chilled water will be circulated It can maintain the panel surface temperature between 18 to 22 deg C. This will ensure the space temperature to be maintained between 24 to 26 deg C.
Why Radiant cooling for precision manufacturing shop floor? Precise Cooling within required control limit > 29 deg is required only for master components and carbon measuring gauges which is only 2 % of the total volume But in those precision manufacturing shop floors all the 100 % area will be maintained within the control limit and temperature variation over time
How radiant cooling can be installed
At The End Of The Day. Continuous Improvement is always better than delayed perfection - Mark Twain