Evaporative Cooling Works in Pharmaceutical Warehouses

Evaporative Cooling Works in Pharmaceutical Warehouses
By Mike Sullivan, Director COSAF Environments

Some cynics within the HVAC industry discourage the use of evaporative cooling in pharmaceutical warehouses. Perhaps that is no surprise as evaporative cooling is currently revolutionising cooling throughout out the industrialised world and offering the air conditioning industry new opportunities to cool buildings with a low carbon footprint.

They are concerned that the evaporative cooling technology is a threat to the livelihoods of those involved in traditional air conditioning. However evaporative cooling is an opportunity for all designers and installers to provide their customers with an effective cooling environment at a cost effective price.

Pharmaceutical storage where a temperature ceiling of 25°c is required to meet the MHRA guidelines is the perfect structure for Breezair evaporative cooling. Breezair’s innovatively designed coolers guarantee that MHRA requirements for temperature storage are met in the most efficient and environmentally friendly way possible. Breezair is the ideal and cost effective alternative to cooling large spaces, which would otherwise incur prohibitive costs to install and run traditional air conditioning in warehouse environments.

FREE COOLING

Uniquely, the Breezair system monitors the outside environment to maximise the benefit of free cooling. Our Intelligent Control System is able to observe the external conditions and allow the system to exploit the external atmosphere to minimise energy consumption but still retain the predetermined cooling requirements of the building.

Therefore the UK climatic conditions create the ideal opportunity for evaporative cooling to keep pharmaceutical warehouses sufficiently cool to meet the MHRA manufacturers requirements during the summer months.

The temperature reduction capability of evaporative cooling is impressive but the additional factor of thermal lag, not understood by some sceptics, is also a crucial factor as to why evaporative cooling can ensure pharmaceutical warehouses are sufficiently cool to meet the MHRA manufacturers requirements. Depending on building design, the thermal lag of the building means that indoor heat-load does not peak in sync with the external solar load, thereby reducing the demand on air conditioning equipment.

As a leading supplier of industrial air-cooling for over three decades, we have the experience and expertise to supply cooling for large areas that meet Indoor Environmental Quality (IEQ) requirements with design temperature guarantees. We are aware that some sectors of our industry are circulating misinformation as a form of protectionism which is almost a Luddite(1) approach.

Because they do not understand the technology, statements are quoted from manufacturers’ literature, which relate to general cooling in buildings which can be sufficiently cooled using Evaporative Cooling, but which do not requiring the stringent requirements of the pharmaceutical industry.

UK CLIMATE - 2005(North London Area Data)

Hottest day was June 19th when temperatures in the area reached 32°c. Under this condition the relative humidity was 30% and under these conditions the Breezair evaporative cooling system would reduce the incoming air temperature by 10°c providing a supply air temperature of 22°c. This was the extreme temperature of 2005, but this temperature was reached at 1.50pm and was maintained until 3.20pm, basically 1½ hours, before and after this time temperatures were lower resulting in lower supply air temperatures into the space. (see graphs below).

2006

Hottest day was July 19th when temperatures in the area reached 34°c. The relative humidity was 23% and under these conditions the Breezair system would reduce the incoming air temperature by 12°c providing a supply air temperature of 22°c. This was the extreme temperature of 2006, but this temperature was reached @ 2.20pm and was maintain until 4.20pm, basically 2 hours. Before and after this time temperatures were lower resulting in lower supply air temperatures into the space.

2007

Hottest day was August 5th when temperatures in the area reached 29°c. Under this condition the relative humidity was 35% and under these conditions the Breezair system would reduce the incoming air temperature by 9°c providing a supply air temperature of 20°c.

The above weather data obviously demonstrates the Breezair performance under the most extreme conditions of the year and these conditions only occur for a short period, during which time the Breezair improves it’s performance.

The Breezair system will maximize the use of cooler outside temperatures (compared with indoor temperatures) when possible, thus “free cooling” the system. It will only operate in its evaporative mode when higher external ambient temperatures are experienced. In the UK our warmer temperatures are associated with lower humidity’s and it is obvious from the above figures that the warmer the temperature becomes outside the more cooling you get inside - this is the fundamental benefit of the evaporative process. (see graphs below)

Birmingham UK - July 2006 Graph

Note:
1. RH% is minimum when Tdb (ambient temperature) is maximum.
2. Also that the T supply (temperature of air from the cooler) is never above the MHRA line at 250C
3. RH% maximum occurs when the ambient temperature is minimum
4. The T supply from the cooler is never near the MHRA line when the RH% is the highest.

Birmingham UK - July 7th 2006 Graph

Note:
1. That at no time during a warm Birmingham day does the temperature of the air from the cooler come near to the MHRA line regardless of what the humidity is doing.
2. The task of maintaining an indoor temperature at or below the MHRA line becomes a function of the air change rate selected for the building.

Legionella Zero risk with Breezair Evaporative Cooling

The Breezair Evaporative cooling system represents a zero risk of Legionella proliferation/transmission. There has never been an incident of Legionella linked to ‘saturated pad’ evaporative coolers, anywhere in the world in the last 60 years.

There are two primary reasons for this:
1) The sump temperature is far below the temperature at which the Legionella bacteria can proliferate and 2) In order to cause an infection the Legionella bacteria must be transported to the victim through the air on a droplet of water called an aerosol.

There are no aerosols discharged into the air stream from a Breezair evaporative air cooler. This claim can be substantiated by reference to independent test carried out in Europe. Finally there are upwards of 300,000 Breezair installations worldwide with a zero record of any problem. That’s without the million of evaporative air coolers installed of all brands around the world. There is no documented case of any of them linked to any Legionella infection since the disease was first identified in 1976. We do, however, advise that regular maintenance should be carried out on Breezair equipment in accordance with local regulations despite these facts. Evaporative coolers should never be associated with cooling towers where the requirement for dosing and maintenance is essential. See our web site for details of our VDI Hygiene certification.

There are no concerns and no risk but the Luddites (1) will still try to convince you otherwise. Don’t be fooled into missing out on the benefits from Advanced natural cooling.

Breezair Evaporative Cooling

The Breezair cooler is the most efficient, environmentally friendly and advanced evaporative cooler in the world today. They are manufactured by Seeley International, which invests over 2.5million euros every year on research and development, and have won numerous awards for their environmental awareness and energy efficiency products including the recent prestigious Dupont award for innovation and UK Building Services Product of the Year Finalist 2008.

The Breezair cooler is some 80% less costly to operate than a standard air conditioning system and contains no ozone depleting refrigerant gasses. The system operates on 100% fresh air. Doors and windows can be left open unlike a air conditioning system which recirculates stale air in the building. The Breezair system eliminates this harmful recirculation of odours, bacteria and all airborne contaminants negating the potential for sick building system. The coolers are externally sited and require only a mains cold water supply and 240 volt electrical supply.

A level of humidity is maintained in the air, which is not dried out by the conventional air conditioning process. The Breezair system supplies a continuous fresh cooled flow of filtered air direct into the environment. A manual variable speed motor is included which allows varying levels of cooling into the space to suit individual requirements.

Winner of numerous awards worldwide including the Dupont award for innovation and UK Building Services Product of the Year Finalist 2008.

(1) The Luddites were a social movement of British textile artisans in the early nineteenth century who protested – often by destroying mechanized looms – against the changes produced by the Industrial Revolution, which they felt threatened their livelihood. This English historical movement has to be seen in its context of the harsh economic climate due to the Napoleonic Wars; but since then, the term Luddite has been used to describe anyone opposed to technological progress and technological change.

The Luddite movement, which began in 1811, took its name from the earlier Ned Ludd. For a short time the movement was so strong that it clashed in battles with the British Army. Measures taken by the government included a mass trial at York in 1812 that resulted in many executions and penal transportation.

The principal objection was to the introduction of new wide-framed looms that could be operated by cheap, relatively unskilled labour, resulting in the loss of jobs for many textile workers. The original Luddites claimed to be led by one "King Ludd" (also known as "General Ludd" or "Captain Ludd") whose signature appears on a "workers' manifesto" of the time. King Ludd was based on the earlier Ned Ludd, who is believed to have destroyed two large stocking frames in the village of Anstey, Leicestershire in 1779, although Ned Ludd is believed to have been a mere simpleton and his actions had no direct relation to those of the later Luddites.[1 (Source wikipedia)