Ceiling fans are most common household appliance after lighting, considering the power consumption in summer it has significant energy contribution for middle and lower middle class people. The power consumption in fans should not be ignored while considering energy planning.
To promote energy efficiency in fans, Bureau of energy efficiency (BEE) in India has included fans star rating system for fans. Where appliance is rated based on performance in scale of one star to five star, Where 1 represents least and 5 represents highest efficiency of appliance. Sample label is shown below:
BEE has set minimum qualification for rating fans, The table below shows minimum value a fan needs to be qualified for BEE star rating system :
|Sr. No.||Fan Blade Size (mm)||Minimum air Delivery (m3/min)||Minimum service Value (m3/min/watt)|
Where Fan Blade Size is the length of wing, Air Delivery is the amount of air delivered per time unit, Service Value is the output per unit of energy consumed.
For rating minimum performance value must be qualified based on their blade span. Further rating has also been segregated based on blade span.
Fan Rating based on length of wings is shown as below –
|Star Rating||Service Value(900mm & 1050mm Fans)||Service Value( 1200mm, 1400mm & 1500mm Fans)|
|1 star||≥ 3.1 to < 3.6||≥ 4.0 to < 4.5 for 1200 mm ≥ 4.1 to < 4.5 for 1400 mm ≥ 4.3 to < 4.5 for 1500 mm|
|2 star||≥ 3.6 to < 4.1||≥ 4.5 to < 5.0|
|3 star||≥ 4.1 to < 4.6||≥ 5.0 to < 5.|
|4 star||≥ 4.6 to < 5.1||≥ 5.5 to < 6.0|
|5 star||≥ 5.1||≥ 6.0|
It is recommended that people should use higher rating fans to conserve energy, comparing energy requirement, 5 Star fans are 40 to 64% energy efficient in different categories of fan length.
Scope of BLDC fans:
For further enhancing the energy efficiency in fans, some companies started using BLDC technology in ceiling fans. BLDC stands for Brushless DC motor and it was invented in 1960.
Let us understand the difference between Conventional induction motor and BLDC technology used for Ceiling fans.
Induction motor fans consist of major components as rotar and stator, when AC current passes though stator winding electrical flux gets generated and fans starts moving. For controlling fan speed either resistance based or regulator or electronic voltage chopping regulator is used.
While BLDC fans consist of majorly three component stator, rotor and electronics, As name suggest these fans are operated on DC current hence SMPS is required to convert AC current to DC current for household application. Use of permanent Magnet used in rotor and electronic reduces power requirement of fans drastically.
Now let us compare BLDC fans with current labelling system of BEE rating:-
|Star Rating||Service Value 5 Star BEE Fans||Service Value BLDC Fans*||% Better than starting point on 5 Star.|
*As per Atomberg Fans manufacturer data
The above table indicates BLDC fans have not only distinctly passes 5 star rating in all categories but also setting new benchmark for energy efficiency.
At present lot of manufactures are coming with BLDC fans for household application and most of the manufactures attracts consumers with 2-3 years of warranty. In present situation BLDC fans looks attractive and is must buy option for increasing efficiency in household appliances.
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