The “Green” switch after the “Earth Hour”

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earth hour logoThere is no doubt that the world is facing more and more environmental challenges.  With all the increasing environmental concerns, many people would agree that we all need to start to save energy and many other resources on earth. 

With the global campaign “Earth Hour” that had just taken place, lights were off for one hour in more than 7000 cities and towns around the world.  It is a very good exercise to get people around the world to do something positive for the environment once a year.  The purpose behind is to inspire people to go beyond that one hour and change their behavior towards a sustainable planet.  A survey conducted by TNS, a global market research consultant company, shows that many of “Earth Hour” participants showed commitment to sustainable living beyond the hour.   So what can we do for the next 12 months before the next “Earth Hour”?

Lighting accounts for about 20 to 30% of electricity consumption at home.  Thus lighting is a good place to start on energy saving.  You may choose to turn off lights at your home for a specific hour every month, or even every night.  It would be a wonderful action plan if you are committed.  You may need to set a daily or monthly reminder on your smart phone to accomplish this commitment though.  What if you turn off lights for an hour one day in a month and you forget to turn lights off for the 10 hours that you leave home for work the other day? You will end up waste more energy than what you saved.

If we take a step back and ask ourselves, there are better options.  The easiest way to save is to stop wasting.  An example would be installing occupancy sensors to eliminate electricity wastage for areas like storage rooms and corridors.  Occupancy sensors can be used for electricity control by detecting movement within a space.  If no motion is detected for a period of time that you have set, it is assumed that the space is empty.  The occupancy sensors will then turn off the lights or air-conditioners automatically.

Ceiling-mount Occupancy sensorSo how do we choose occupancy sensors? To start, it would be helpful to know the types of occupancy sensors available in the market.  There are three types of occupancy sensors: passive infrared (PIR), ultrasonic, and dual-tech (PIR + ultrasonic). PIR sensors detect motion by sensing temperature profile changes.  They usually detect relatively large body movement and are most suitable for enclosed spaces.  Ultrasonic sensors, on the other hand, operate like radars and can sense the tiniest movements by interpreting change in frequency.  The effectiveness will drop in high-ceilinged rooms and spaces with high levels of vibration or air flow though.  Dual-tech sensors combine both PIR and ultrasonic technologies.  They can activate lights when both technologies detect motion while eliminating possible false on or off. 

There are many other ways to stop wasting energy.  Occupancy sensor that acts like a “Green” switch is one of the simple ways to help us stop wasting energy.  To go further, you may want to consider a smart home with energy monitoring products.  Share with us on your planning on energy efficiency after the “Earth Hour”.

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  • With all the increasing environmental concerns, we should start and act quickly for saving energy. Occupancy sensor is the easiest way to save energy at home, however, this usage is not so popular in Asia. It would be great to have more people in Asia to know how occupancy sensor can save energy easily at home.

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