Everyone seems to be obsessed with using less these days, an altruistic endeavor they call “going green” or “reducing your carbon footprint.” To that end, energy consumption has been placed squarely in the crosshairs. But wait… I still need to stay cool in the summertime! Is there any way I can keep cool, go green, and reduce my carbon footprint? Why yes… yes there is. It’s called evaporative roof cooling, and I implore you to read on…

An evaporative roof spray system intermittently sprays a thin film of water on the roof surface, and then allows the water to evaporate. When performed in regular cycles, this prevents the roof from getting hot and transferring that heat into the building. Since 50% of the heat load inside a building comes from the roof, the result is lower interior air temperatures. For air-conditioned facilities, evaporative roof cooling can also reduce the load on the HVAC system, producing immediate energy savings.

Looking for alternative ways to stay cool this summer? Interested in evaporative cooling? Have lots of questions? Great! We're here to help you figure it out! With over 40 years of expertise, we can design a system that fits seamlessly on your roof – providing hassle-free cooling for years to come!

We hope you're reinvigorated and getting started on planning your year, or if you're really good, you’ve already started on projects! The beginning of the year is also a perfect time to evaluate your ventilation needs. You may already have a list of what must be replaced, added, or upgraded, and are already deciding project timelines and goals. This is good! If not, you may need a bit of help figuring out the right amount of fresh air to get moving through your facility so you know what products to get. This is where we can help. It’s vital to your employees’ safety, comfort, and productivity to get the bad air out and the fresh air in.    
 
So, how do you accurately calculate your ventilation needs? It starts by determining the rate at which you need to completely replenish the volume of air in a given room. This is known as an air turnover (or air change) rate and is usually expressed as number of air changes per hour (although it can sometimes be seen as “minutes per air change”). The number of air changes needed ultimately depends on the type of facility or the work being done in a particular area.  For example, a typical warehouse should change air approximately 12 times an hour, though this can vary between 6 and 30.  By contrast, a garage needs to replenish its air 20 times in an hour to protect employees against heat buildup and noxious fumes.
 
Once the air change rate is determined, we can proceed with our calculation. For purposes of this article, we’ll make the math easy (because… hey… who doesn’t love easy math?!). Let’s say you have a 100’ x 100’ building with a 25’ ceiling height.  Based on the work being done, we’ve decided on 12 air changes every hour. Your calculation would look like this:
 
100’ x 100’ x 25’     =      250,000 ft³ 
                                              60/12         =    50,000 CFM
 
Based on our calculation above, you would need to move 50,000 cubic feet of air per minute (CFM) through your facility in order to achieve 12 complete air changes an hour.
 
Being responsible for ventilation in your facility doesn’t have to be difficult. So now that you know your ventilation needs, what’s next? Why not call Patterson?! We have the people, the products, and the knowledge to help you build the ventilation system of your dreams! And be sure to check out our new ventilation brochure. It’s packed full of product specs, proper placement suggestions, and more!

Have you ever agonized over the purchase of a new A/C system at home?  Perhaps more energy efficient windows or better insulation?  Usually, the first question you ask (after, of course, “that’s going to cost HOW much?!”) is, “how long before this pays for itself?”  When it comes to evaluating potential capital expenditure projects (whether at home or at work), one acronym stands above the rest – ROI, or return on investment.  If you’re considering HVLS fans for your facility, calculating ROI helps estimate the time period necessary for full payback in the form of energy savings.  But how are these calculations done, and what critical information is needed to do them?  Keep reading to find out!
 
Energy savings from HVLS fans are generally realized during the winter months, due to destratification.  Because of this, knowing your heating cost and consumption information is vitally important, as HVLS fans can help reduce them both by up to 30%!  Also important is the cost of your electricity, since heaters consume electrical power as well as natural gas when they are in use.  Other inputs that help “fine tune” your ROI calculation include:  facility square footage, hours of operation, number of heaters, heater voltage and amperage ratings, and average length of the winter heating season.
 
So how is all this data used to calculate ROI?  It all starts by estimating current resource consumption costs (both natural gas and electrical – I will spare you the boring formulas here).  Once a total consumption amount is determined, calculate a projected savings amount as a percentage of that total consumption (15-20% is usually a solid, conservative savings estimate).  Then, subtract your fan electrical costs (again, boring formula) from your savings – this is your net savings amount.  Finally, divide your net savings by the projected cost of your new fans and – Bob’s your uncle – you have ROI (in number of heating seasons)!  Pretty easy… right?!
 
Of course, as with any calculation, the result should be used as a guide toward making an informed cap-ex budget decision.  It should not be taken as “gospel,” as any number of factors can affect the actual savings amount (e.g. price of natural gas, unusually harsh or mild winters).  But overall, an HVLS ROI calculation can provide valuable insight into current resource consumption issues, and identify potential air movement solutions.
 
Want to learn more about ROI calculations for HVLS fans?  Give your regional Patterson sales representative a call today, and let them introduce you to our High-5 fan. You’ll soon be spinning your way to lower heating costs this winter!  

​Well, guess what?  It’s summer again.  And – lo and behold – it’s scorching hot out there.  While the extreme heat may send you running for the nearest swimming pool, it can also cause reduced productivity and dangerous medical complications in the workplace.  Let’s dive a bit deeper. (See what I did there?)

Could your facility answer ‘yes’ to any or all of the following?

• Does employee productivity decrease during the summer months when temperatures are elevated?
• Do employees complain about the lack of airflow in the workplace?
• Do processes or equipment produce heat that could be dissipated by air circulators?
• Do certain manufacturing or assembly processes create a large amount of condensation?
• Are there products or components that should be cooled after manufacturing?

So what can be done to neutralize this formidable opponent?  How about the all-important one-two punch of air movement?

ONE: VENTILATE
Moving air through supply and exhaust ventilation not only cools the workplace environment and makes it more comfortable, it also helps control airborne contaminants. Industrial ventilation can also help prevent the buildup of noxious fumes, fire, and odors. Exhausting the hot air from your facility will go a long way toward keeping the temperature, humidity, and air quality at a safe level.


TWO: CIRCULATE
Without movement, air can stratify and stagnate, creating pockets and layers of hot, humid air. In addition, heat leaves our body more quickly when a breeze is present. Fans create airflow that quickly evaporates perspiration from our skin, carrying away heat. The airflow also reduces the thickness of the hot, humid layer of insulating air that builds up around our bodies, thus improving heat dissipation. In short, fans make our natural cooling mechanisms more efficient. Use high-volume, low-speed ceiling fans and portable fans to improve air circulation and natural cooling.


So there you have it!  The one-two punch to knockout heat stress and keep your employees safe, happy, and productive this summer.  And, as always, trust Patterson to be there with the right product for every air movement application.  From ventilation to circulation, Patterson’s got you covered!

Oh the places you go! With everyone on the move nowadays, we find ourselves continually changing locations, even while on the job.  Maybe you’re shifting from one aisle to the next, or finished a task and are moving on to the next in a separate area. Whatever the reason may be, you’ll want to be able to take your cooling with you. That’s where Patterson’s Shop Floor Fans (Drum Fans) come in!  With 30 and 34 inch sizes, these fans deliver incredible airflow – and can easily be wheeled from one place to another! Lightweight, durable, and quickly assembled, Patterson's Drum Fans are ideal for small work areas, garages, or any facility that needs versatile, mobile air movement.

It may not be warm yet, but rest assured – it’s coming!  Now is a great time to assess your cooling needs and get a jump on the hot weather. Whether it’s large open areas, aisles, mezzanines, or work stations, Patterson has you covered! 
 
Not sure what you need?  That’s why we’re here!  Give us a call and put Patterson’s nearly 30 years of air movement expertise to work for you! ​

So, hopefully by now you’ve recovered from all the holiday gaiety.  And, yes, many of you across the country are looking out your windows at snow and sub-zero temperatures.  But guess what?  That snow and cold will soon be replaced by sunshine and warmer temperatures.  Since you know it’s coming, what better time than now to assess your fan needs and perform maintenance on the ones you have?!

Planning out your fan needs during the winter months is a great way to get a head start on the inevitable hot, stagnant air brought by summer.  Has your facility expanded in the last few months?  Are there any areas that weren’t addressed last year?  Have any new processes been introduced?  Discussing these and other fundamental questions with your Patterson sales rep will yield myriad solution possibilities, and show your employees that you’re thinking ahead when it comes to their health and safety!

What about the fans you already have?  Well, now is the perfect time to make sure they’re working properly.  Clean fan guards and blades.  Tighten mounting bolts.  Check electrical connections and overall functionality.  Something not working quite right?  No problem!  Give us a call!  We’ll make sure you get the correct parts to keep those fans running smoothly when they’re needed most!

Whether it’s new fans or maintaining old ones, call Patterson now to ensure your facility has the coolest summer ever!

Not everyone works in open spaces, but everyone does deserve the same cooling benefits.  So if you're looking for an affordable way to cool your employees in those small, confined workspaces, then look no further than Patterson’s 10-inch “Bully” fan!  Don’t let its size fool you… this fan really packs an air movement punch!  It’s perfect for small areas where spot coolers and large cage fans just can’t reach!  And with its yoke, pedestal base, and truck cooler arm mounting options, you have numerous ways to deliver essential workstation cooling.
 
Need to cool more than just a workstation?  Patterson is here to help!  Whether it's high volume, high velocity, or supply and exhaust, we have just the right solution to meet all your facility air movement needs!

​Not everyone works in open spaces, but everyone does deserve the same cooling benefits.  So if you're looking for an affordable way to cool your employees in those small, confined workspaces, then look no further than Patterson’s 10-inch “Bully” fan!  Don’t let its size fool you… this fan really packs an air movement punch!  It’s perfect for small areas where spot coolers and large cage fans just can’t reach!  And with its yoke, pedestal base, and truck cooler arm mounting options, you have numerous ways to deliver essential workstation cooling.
 
Need to cool more than just a workstation?  Patterson is here to help!  Whether it's high volume, high velocity, or supply and exhaust, we have just the right solution to meet all your facility air movement needs!

Check the calendar.  Guess what?  It’s June.  What does that mean?  It’s going to get hot very soon (if it hasn’t already).  What else does it mean?  You’re going to want fans for your facility – lots of them – quickly.  Not only do you need them fast, you need them mounted and installed fast, too.  Well, we here at Strait Talk (and, yes, Patterson too) also have these goals, and we want to help you avoid any “hiccups” in the process.  So, whether it’s placing an order or tightening the last bolt, here are some tips to “breeze” through your Patterson experience!

• What is your application?  Are you trying to move air down aisles, pick modules, mezzanines, or in trailers?  Then take a look at Patterson’s line of high velocity fans or the new db.  Open areas?  Think about the High-5 HVLS ceiling fan.  Small area cooling?  Patterson’s Fabric Air Ducts, Drum Fans, Cage Fans, and Evaporative Spot Coolers will do the job.

• Know your electrical source.  Is it single phase or three phase power?  277 Volt?  Ordering the right motor type will save time, money, and the hassle of returns/reshipments.
• Will your desired fan fit in the designated area?  If you’re not sure, take some measurements and give your Patterson sales rep a call to discuss.  That’s what they’re here for!
• So your fans have arrived….great!  Now what?  Well, as a wise man (my father) once said, “When all else fails, read the instructions.”  Take a few minutes to familiarize yourself with any installation instructions that came with your fan or fan mount.  If you ordered a High-5, pay special attention to the section on wiring the fan’s variable frequency drive (VFD).  Doing this may help answer some questions, and/or prevent any confusion for you (or your installer) during the setup process. 
• IMPORTANT!  All Patterson fans, regardless of type, come with a wiring schematic (usually printed on the nameplate of the motor).  Be sure to wire your fans exactly as shown.  In the case of a dual voltage motor, take care to select the correct wiring configuration based on your voltage level (usually 208-230 V or 460 V 3-phase service).  Have electrical questions?  Call before you connect – improper wiring can damage motors/VFDs and affect warranty coverage!
• ALSO IMPORTANT!  ALWAYS install all safe guards that come with your fan and/or mount.  They are designed to protect you, your personnel, and your facility in the unlikely event of a failure. 

So there you have it – some simple tips to make your fan buying experience smooth as silk from start to finish.  And as always, Patterson sales reps are standing by ready to dispense timely fan advice and provide free quotes for all your fan needs. 
​
Until next time, let’s keep ‘em cool out there!

We all love to have our cake and eat it, too.  But, as anyone in a successful marriage will tell you, life is about compromise.  (Seriously ladies, you can’t have it YOUR way EVERY time!)  In the air movement business, a trade-off exists when evaluating a fan’s performance versus the noise level it produces.  So how much noise is too much?  When is it ok to use a quieter, lower performance fan?  How do you strike the perfect balance between necessary air flow and acceptable sound levels?  Answers forthcoming!
 
Before we go much further, let’s talk about the different fan types.  High velocity (HV) fans are generally considered high performance – designed to accelerate (or “throw”) air over a distance.  For HV fans, airspeed (measured in feet per minute, or FPM) is more important than volume.  However, this also translates into slightly higher noise levels, typically measured in decibels (dBA).  The other end of the performance spectrum includes cage fans and ventilation fans (think supply, exhaust, shop floor, etc.).  These fans covet volume over speed, and are usually rated in cubic feet per minute (CFM).  Are they quieter than HV fans?  Absolutely… but you won’t feel their airflow once you move more than a few feet away.
 
So which fans are right for your facility, and how should they be used?  Well… both… and it depends!  (How’s that for an answer?!)  For an effective overall air movement solution, it is best to incorporate both fan types.  For example, use large supply and exhaust fans for cross ventilation, and couple them with HV fans to accelerate air movement from one end of the building to the other.  This works particularly well if your aisle ways run parallel to the airflow.  If noise abatement is an issue (industry standard tends to put an upper limit around 80 dBA), mount HV fans well above the floor on columns or racks.  If small area “spot cooling” is needed, employ one or more shop floor or cage fans – allowing for airflow without violating any noise level requirements. 
 
So… maybe that example doesn’t fit the layout of your facility.  Perhaps you’re looking for both performance and low noise?  Great!  Give Patterson a call and learn more about their new db fan!  It offers the performance of an HV fan, with a 70% reduction in noise level!  No matter the fan type, Patterson has the products and the expertise to keep your facility cooler, safer, and more productive!  

​If you’ve been reading Strait Talk on a monthly basis (and I KNOW you have), you’ve learned that the Patterson High-5 HVLS fan is a great way to destratify heat in the winter.  But did you know you can accomplish the same goal using Patterson’s Power Tube and high velocity fans?  You didn’t?!  Well that, dear readers, is why we’re here!

Patterson has been utilizing its fan/Power Tube combination for years to deliver cooling to a large area, while using only a single fan.  But this same configuration can be used during the winter months as well.  Fan/Power Tube combos placed near the ceiling can help transfer heat from elevation back down to the working level, where it’s needed most.  The same concept can be applied to open-ended Power Tubes, which can move and distribute heat from one area of your facility to another.  This fan/Power Tube setup is a great option for smaller facilities, low ceilings, or areas that might not otherwise accommodate a much larger HVLS fan.

Whether heating or cooling, a Patterson Power Tube is an economical yet effective way to deliver employee comfort 12 months a year!  To learn more about this and other quality air movement solutions, contact your Patterson sales representative today!

What comes to mind when you think of the word cage?  Perhaps a place to keep your parakeet, or “Gone in Sixty Seconds” (as in Nicholas Cage – get it?!).  But “cage” also has meaning when referring to a type of industrial fan.  So what exactly is a “cage fan,” and when is the right time to use it?  Please – read on, dear friend!
 
A cage fan is really just a larger, stationary version of the oscillating fan you may have in your home or office.  Often they are mounted to a simple pedestal, but in some cases can even mount to a pole, column, or other building structure.  Most cage fans are considered “budget fans,” since they are usually much cheaper than their high velocity (HV) counterparts.  However, while they may not cover as much area as an HV fan, cage fans are undoubtedly useful in certain situations. 
 
Individual workstations are an ideal place for a cage fan, as they generally do not require the power and coverage of an HV fan.  Multiple speed settings allow the user to adjust the air movement to their preference, a feature not typically found on an HV fan.  Also, cage fans are great for areas that have noise level requirements, but still need air movement.  Their lower decibel readings provide quieter, individualized relief during the cooling season.
 
Not sure which fan is right for you?  No problem!  Patterson’s friendly, knowledgeable sales staff is ready and eager to help you with all your air movement/people cooling needs!  Give them a call today! 

When it comes to evaluating potential capital expenditure projects, one acronym stands above the rest – ROI, or return on investment.  If you’re considering HVLS fans, calculating ROI helps estimate the time period necessary for full payback in the form of energy savings.  But how are these calculations done, and what critical information is needed to do them?  Keep reading to find out!

Energy savings from HVLS fans are generally realized during the winter months, due to destratification (see Strait Talk, February 2015).  Because of this, knowing your heating cost and consumption information is vitally important, as HVLS fans can help reduce them both by up to 30%!*  Also important is the cost of your electricity, since heaters consume electrical power as well as natural gas when they are in use.  Other inputs that help “fine tune” your ROI calculation include:  facility square footage, hours of operation, number of heaters, heater voltage and amperage ratings, and average length of the winter heating season.

So how is all this data used to calculate ROI?  It all starts by estimating current resource consumption costs (both natural gas and electrical – I will spare you the boring formulas here).  Once a total consumption amount is determined, calculate a projected savings amount as a percentage of that total consumption (15-20% is usually a solid, conservative savings estimate).  Then, subtract your fan electrical costs (again, boring formula) from your savings – this is your net savings amount.  Finally, divide your net savings by the projected cost of your new fans and – Bob’s your uncle – you have ROI (in number of heating seasons)!  Pretty easy… right?!

Of course, as with any calculation, the result should be used as a guide toward making an informed cap-ex budget decision.  It should not be taken as “gospel,” as any number of factors can affect the actual savings amount (e.g. price of natural gas, unusually harsh or mild winters).  But overall, an HVLS ROI calculation can provide valuable insight into current resource consumption issues, and identify potential air movement solutions.

Want to learn more about ROI calculations for HVLS fans?  Give your regional Patterson sales representative a call today, and let them introduce you to our High-5 fan. You’ll soon be spinning your way to lower heating costs this winter! 
 
*Actual savings depend on heating costs, size of facility, number of fans, and other factors

It’s that time of year again – trips to the beach, backyard barbeques, and of course…the loading/unloading of sweltering hot trailers.  Employees of distribution centers and other facilities are faced with this grueling task each and every summer.  In many cases, these trailers are left sitting for days before they’re brought to the dock area – creating an oven effect by trapping in heat from prolonged sun exposure.  Temperatures can reach in excess of 130°F!  Fortunately, Patterson has worked to mitigate this issue with their TC (Truck Cooler) 18-inch fan and HVTC (High Velocity Truck Cooler aka “the Whistleblower”).  However, a fan is only effective if it’s used properly, so this month we’ll focus on getting the most relief from your Patterson truck cooling solutions.

The prevailing myth amongst dock area employees is that they must point fans directly at them to receive the maximum benefit.  Yet this will only provide temporary relief when at or near the dock door opening.  As the employee moves away from the dock door, they will begin to feel less air movement – eventually reaching an area of hot, stagnant air that remains at the front of the trailer.  Working in this condition for long periods can bring about the symptoms of heat exhaustion or heat stroke if not dealt with appropriately.

So how can we optimize air flow?  Very simply, the fan needs to be positioned in one of the upper corners at the dock door opening and aimed toward the same corner at the front of the trailer.  Doing so will allow air to reach the entire length of the trailer – evacuating the trapped hot air and creating a constant airflow.  Having this continuous movement of air will alleviate many heat stress issues and provide an overall safer work environment on even the hottest of summer days.

Looking to cool more than just your trailers?  Check out Patterson’s new db fan – it’s quieter, takes up less space, and is unlike any air movement product you’ve ever seen!  As the weather heats up, be sure to call the experts at Patterson – your employees will thank you!

Location, location, location!  Any real estate agent worth their salt knows these three “principles” are the key to finding a great home.  But location is also important when it comes to the placement of your HVLS (High Volume Low Speed) fans.  Putting the right fan, in the right place, at the right height will provide a comfortable work environment regardless of season.

As mentioned in a previous article, HVLS fans work best over open areas where air can move freely ceiling to floor, then outward in all directions.  For this reason, fans should not be placed near walls or other obstructions, since these may limit airflow and effective coverage area.  Ideally, each fan should be between 20 and 25 feet above the floor, using extensions (known as downrods) where necessary to achieve optimum height.  Facilities with very tall ceilings will need multiple fans spaced closer together to provide ample air movement at the working level, as ideal fan height may not be possible.

Other factors to consider when placing HVLS fans:

• Avoid mounting the fan underneath any area lighting.  This will prevent the “strobing effect” when the fan is in operation.

• Blade clearances are critical!  Hanging a fan too close to potential obstructions (chain suspended lighting for example) can create a safety hazard.  A good rule of thumb:  blade clearances should equal 15% of the fan’s diameter in all directions.  Example:  a 24 foot fan should not have any potential obstruction closer than 3.6 feet.

• Pay particular attention to the routing of the fan’s control cable (between the fan and the control keypad near the floor).  If possible, run this cable in conduit, or in such a way as to avoid lighting fixtures.  Doing so will reduce the possibility of signal noise and fan operational issues.

Still have questions?  As always, the air movement experts at Patterson are a phone call away!  Put their HVLS experience to work in your facility!

Everyone seems to be using less these days, an altruistic endeavor they call “reducing your carbon footprint.”  To that end, energy consumption has been placed squarely in the crosshairs.  But wait... I still need to stay cool in the summertime!  Is there any way I can keep cool AND reduce my carbon footprint?  Why yes… yes there is.  I implore you to read on…

A study by the University of Stellenbosch in South Africa investigated a number of cooling alternatives and their effect on a one-room building.  The results were decisive:  evaporative roof spray showed the largest reduction in cooling load (59%) and the largest overall reduction in net energy transferred (72%).  Researchers also found that by continuously cycling cool ambient air through the building at night, and then using an evaporative roof spray system during the day, cooling load and energy transfer reductions improved an additional 5% and 8%, respectively.  This application is known as flywheel cooling.     

FLYWHEEL COOLING SYSTEMS AT A GLANCE

Night flushing is simply the movement of cool night air through a building by means of a ventilation system.  Generally, this system consists of at least one wall-mounted supply fan in conjunction with one or more wall- or roof-mounted exhaust fans.  Cross ventilation is important, so fans should be placed in such a manner as to allow air flow from one side of the facility to another.  Effectiveness is primarily due to air flow rate, expressed as air changes per hour.  Studies vary widely on the optimum number of air changes per hour, ranging from 10 to 30. 

An evaporative roof spray system intermittently sprays a thin film of water on the roof surface, and then allows the water to evaporate.  When performed in regular cycles, this prevents the roof from getting hot and transferring that heat into the building.  The result is lower air temperatures, and a reduced cooling load on the facility HVAC system. 

PRACTICAL APPLICATION

Most industrial sites can benefit from the use of flywheel cooling.  The ideal schedule would call for the supply and exhaust fans to be turned on at the end of the workday (or for a 24 hour operation, around 8 – 9 pm).  The fans would then circulate air through the facility until around 7 or 8 am the following morning.  At that time, the area should be “buttoned up” to retain as much of the cool night air as possible.  Then, the evaporative roof cooling system would be activated, preventing the sun’s radiant heat from penetrating the building.  The end result would be lower interior temperatures, since nearly 50% of the generated heat load inside a given structure emanates from its roof. 

BENEFITS

For sites that use large HVAC systems, incorporating flywheel cooling into the daily operations plan translates into direct energy savings and reduced electrical consumption.  Night flushing and evaporative roof spray greatly diminish the building’s cooling load, decreasing HVAC cycle frequency and duration.  Large consumers of electricity will also see an additional benefit of lower peak demand charges and ratchets often imposed by power companies.  The University of Stellenbosch study agrees, stating these methods “…not only constituted a saving in the energy consumed by a conventional air conditioner but also decreased the required size of the air conditioner.”  

The university study highlights another important point regarding air conditioning capacity.  In many cases, cooling load reductions may be dramatic enough to pull unneeded A/C tonnage offline entirely, bringing down yearly HVAC maintenance costs.  Facilities located in more moderate parts of the globe could take things even further: “…in milder climate conditions the necessity of a conventional air conditioner may be averted.”

Regardless of climate, HVAC capacity, or industry, environmentally and safety conscious organizations would do well to explore the prospect of adding flywheel cooling to their facilities.  The rewards of lower energy bills, more productive employees, and a carbon footprint reduction await.

REFERENCES

Artmann, N., Manz, H. & Heiselberg, P., (2008).  Parameter study on performance of building cooling by night-time ventilation, Renewable Energy, Vol. 33, pp. 2589-2598

Dobson, R. & Vorster, J., (2011).  Sustainable cooling alternatives for buildings, Journal of Energy in South Africa, Vol. 22, No. 4, pp. 48-66

Finn, D., Connolly, D. & Kenny, P., (2007).  Sensitivity analysis of a maritime located night ventilated library building, Solar Energy, Vol. 81, pp. 697-710

Geros, V., Santamouris, M., Tsangrasoulis, A. & Guarracino, G., (1999).  Experimental evaluation of night ventilation phenomena, Energy and Buildings, pp. 141-154

World business council for sustainability, [Online].  Available: http://www.wikipedia.com/theinnovationchain. [2009, October 16].