Although fans in themselves are not major power consumers, given the large number of fans in a greenhouse, it may still pay to look into this. With a simple calculation, thg team with Vostermans provides insight into the current power consumption and what a modern alternative can provide.
In the example, the number of ventilators in the greenhouse is determined on the basis of a circulation rate of 3. "This circulation rate may vary per situation or crop, but this example gives a realistic indication for one specific situation", the team says.
Current situation and fan
"In the current situation, we assume a greenhouse of 160,000 m3. If we multiply this by the circulation rate of 3, we know that the circulation fans must move 480,000 m3 of air per hour", they continue. "The commonly chosen fan in the past was the 1~ 230v fan that moved 5,350 m3 per hour with a current draw of 240w. In the old situation, to move 480,000 m3/h of air you needed 90 fans that collectively consumed 21,600 watts per hour. "
New fan option 1.
This example chooses a Horticultural fan from the new, energy-efficient 5,000 m3 line. "This 1~ 230v fan moves 4,850 m3/h at a power consumption of 119w. In order to move 480,000 m3/h of air, 99 fans are now required that collectively consume 11,781 watts per hour. This is an energy saving of 45.5%. Thus, the fans may pay for themselves in a short time."
New fan option 2
In this example, they are going for a fan from our more powerful 7,000 m3 line. This new 1~ 230v fan from this line moves 6,450 m3/h with a power consumption of 190w. "To move 480,000 m3/h of air now requires 74 fans that collectively consume 14,060 watts per hour. This is still a 35% savings and you need fewer fans!"
What will this save me?
Of course, saving energy is not the only thing. "The purchase price, installation costs, transportation costs and local energy prices all affect the total investment and payback period. But it can certainly pay off, then, to invest in more fans that are more energy-efficient."
For more information:
Vostermans Ventilation
www.vostermans.com