hectare needs to be removed from the site or recycled each day. This aspect is crucial from the outset
as it involves both ground slopes and greenhouse
gutter slopes. It requires a meeting of minds
between the greenhouse designer, the land leveller,
who will cut-and-fill and the irrigation designer. The
norms for the ground slopes are as follows.
Parallel to the dripper lines (gutters) and crop row
direction. 1,0% < slope < 2,0%
At right angle to the dripper lines (parallel to the
gable side). 0,25% ≤ slope < 2,0%
Figure 4. Elevated irrigation equipment in the head
control
Greenhouse design
The irrigation design needs to fit in with the greenhouse design: inside and outside, which needs coordination between the irrigation designer and the
greenhouse designer. Buried pipes for instance cannot be laid within 300 mm of concrete foundations.
Multiple dedicated mainlines outside the greenhouse
need room to be laid, generally 300 mm between
mainlines.
Climate control
Climate control design and planning is undertaken
by the greenhouse designer but the actual climate
controller is often selected and installed by the irrigation designer.
Electricity supply
Electrical power is supplied to irrigation and nonirrigation equipment. An integrated electrical supply
system must be designed.
Irrigation equipment includes:
Irrigation, service water and cooling systems.
Fertiliser equipment.
Automation and communication
Non-irrigation equipment includes:
Greenhouse motors – fans, vents, curtains,
screens, pad pumps.
Heating.
Lighting – head control, greenhouse, outside.
General supply
Automation and communication
Figure 5. Pipe work installed in covered concrete
trenche
This equipment shares an electric supply with common wireways and cable sleeves. There must be a
common surge and lightning protection programme.
It is important that different voltages are kept separate. For instance, sensor cables (extra low voltage)
and particularly communication cables should not
share wireways / sleeves with 230V / 400V (low volt-