Door closed due to aircon

How often do you see that in high summer. Butchers, grocers and small shops, all desperately trying to keep their doors shut in order to keep cool air in, naturally resulting in customers being kept out.

Our evaporative coolers are full fresh air systems. What this means is that our cool air requires you to keep your doors and windows open in order evacuate the "used" air.

There is a much better natural fit between evaporative cooling and shops since:

• The operational cost of evaporative cooling is a fraction of conventional cooling because of the reduced electrical load. 
• The total amps drawn by the evaporative coolers is much smaller than conventional cooling. 
• Because evaporative cooling provide bigger volumes of cool air, rather than the small volumes of very cold air produced by conventional cooling, you obtain a fresh breeze in the shops. 
• But most significantly is that fact that evaporative cooling wants you to open doors and windows in order to evacuate the cold air and allow the injection of new fresh air.

South African Government departments turn to Evaporative Cooling

The Department of Environmental Affairs recently bought 24 Evaporative coolers from Protek to provide cooling for their flagship offices in Pretoria.

What makes the project unique is not only that the whole building has been done using two stage evaporative cooling, but that the building also received a 6 star energy efficient rating.

Not only was two stage evaporative cooling instrumental in acquiring the 6 star rating but also worked out much cheaper than a conventional cooling system in both running and capital costs.

Factors such as limited supply and the escalating cost of electricity is driving large office buildings to consider evaporative cooling.

And evaporative cooling has progressed to the point where consistent supply temperatures can be achieved in order to provide effective cooling to buildings using only water.

The DEA is the second government department after the Department of Trade and Industry (DTI) who makes use of Protek evaporative cooling.

Pretoria climate data with IWAC supply temperatures

Here is the Pretoria climate data posted before, but with the IWAC supply temperatures super imposed.

The lines indicate the number of days per year that the IWAC will provide supply air above the specific temperature datum.

Pretoria climate data

Included is a 2D histogram for Tdb/Twb for the Pretoria Forum, 14h00, 1956-1960 for the months Dec-Feb.

Here is the actual bin data for the graph above.

Unit images

A Compact Single Stage with centrifugal fan

A Two Stage cooler connected to vertical ducting

The Two Stage unit seen from the side. Note the dry cooling coil (loads of small copper pipes protruding from the side)

A number of small Single Stage units ready for loading

Two Stage double units where the secondary air is blow out vertically and the primary air horizontally

A Two Stage evaporative cooler mounted on a roof