Although fans are not major power consumers in and of themselves, it may be worthwhile to examine this, given the large number of fans in a greenhouse. With a simple calculation, we can offer insight into the current power consumption, and what a modern alternative could yield. In the example, the number of fans in the greenhouse was determined based on a circulation rate of 3. This circulation rate may differ per situation or crop, but this example offers a realistic indication for one specific situation.
Current situation
In the current situation, our assumptions are based on a greenhouse of 160,000 m3. If we multiply this by the circulation rate of 3, we know that the circulation fans have to move 480,000 m3 of air per hour.
Current fan
In the past, the 1~ 230v fan that moved 5,350 m3 per hour with a power consumption of 240w was most commonly chosen. In the old situation, it took 90 fans in order to move 480,000 m3/h of air, which together consumed 21,600 watts per hour.
New fan option 1
In this example, a Greenhouse Fan from the new, energy-efficient 5,000 m3 line is selected. This 1~ 230v fan moves 4,850 m3 per hour at a power consumption of 119w. To move 480,000 m3/h of air, 99 fans are now required that together consume 11,781 watts per hour. This results in an energy saving of 45.5%, so the fans will pay for themselves in a short amount of time.
New fan option 2
In this example, we are going for a fan from our more powerful 7,000 m3 line. This 1~ 230v fan from this range moves 6,450 m3 per hour, with a power consumption of 190w. To move 480,000 m3/h of air, 74 fans are now required that together consume 14,060 watts per hour. This still constitutes a saving of 35%, with the added bonus of needing fewer fans!
How much will this save me?
Needless to say, saving energy is not all that matters. The purchase price, installation costs, transport costs, and local energy prices all affect the total investment and the payback time. Nevertheless, investing in more fans that are more economical in use can certainly pay off. Please contact your dealer or installer for the most economical solution, or talk to one of our specialists.
For more information:
Vostermans Ventilation
https://www.vostermans.com/ventilation/greenhouse