Image courtesy of Esco Ducted Fume Hood

Today, more and more companies are transitioning their laboratories to a GREENER one. Why? Simply because of the idea of SAVING MORE and being green is more sustainable and practical. We are constantly pushing technology a notch higher for a more efficient devices, that's why we have LED TVs, smart washing machines, smart cars, LED bulbs and more.

Laboratories are touted to be huge energy spenders with consumption of about four times more energy than offices of the same size. One common culprit is your fume hood! There are systems for your fume hoods that you can implement in your laboratory to help reduce energy wastage. These systems shown below may be installed individually or in various combinations.

• Auto Sash Sensor
• Install an automatic fume hood closure system that uses motion sensors to assess whether a person is working in front of the hood or not. When no activity has been detected for a certain period of time, the hood's sash will be lowered automatically.

• Variable Air Volume (VAV) Fume Hoods
• This has been previously discussed (click here). I've differentiated the advantage of a VAV system over a CAV one. This type of hood is often combined with the auto sash sensor noted above and allows the fume hood to interface with the laboratory's HVAC system. As the sash is raised or lowered, the VAV controller will signal with the HVAC system to control the volume of air to be exhausted either thru the automatic adjustment of  the fan speed or position of the damper.

• High Performance Fume Hoods  

Esco Frontier Acela, a High Performance Fume Hood (Image courtesy of Esco Ducted Fume Hood)

• These re energy-efficient fume hoods capable of containing fumes at a reduced face velocity, hence, reduced exhaust volume. This directly translate more savings for the company.
  
  
  

Fume hoods are literally huge energy spenders, with each one consuming more energy than three average homes in the US. You gotta watch this video which pretty summarizes how this problem can be addressed. Check it out!


Based on the video shown above, here are the hard facts:

• Estimated annual energy consumption for conventional fume hoods is around US$9,000 based on face velocity of 0.5 m/s (100 fpm) at full sash open position for 1.8 m (72”) hood. 
• The annual energy consumption of a conventional hood is equivalent to the consumption of around 3 average homes in the US.
•  A new line of high performance, low-flow fume hoods were engineered to help reduce energy consumption. These efficient hoods operate safely at a reduced face velocity of 0.3 m/s
• With the reduced face velocity, energy consumption can also be reduced dramatically . 
• In using a high performance hood, it is estimated for the exhaust volume to be reduced by 58%. This translates to an annual savings of US$ 5,600.

If you are part of the team on the procurement and designing (or retrofitting) of your laboratory, it is also your job to decide whether the fume hood you're planning to install should have a Constant Air Volume (CAV) or a Variable Air Volume (VAV). Why do we think it's important? An average fume hood exhausts around 750 to 1,000 cubic feet per minute of conditioned air, hence, imagine the amount of load it's putting on the lab's HVAC system. If not well planned, this will negatively impact the operating costs of the laboratory.

Don't be overwhelmed by these terminologies as these "jargons" will be thoroughly explained with photos I personally created.

The "Shut the Sash" campaign above is courtesy of Esco, taken from their facebook account.