Performance
Under what conditions will
the Ferguson Windmill pump 500 gallons (2300 liters)
per day?
With an average wind speed of 16 mph (7 m/sec), a
6-feet (1.8-m) lift, and a 40-foot (12.2-m) head.
For
an 80-foot (24.4-m) head, a 32-mph
(14-m/sec) wind speed is needed.
Similarly, if the lift is increased, a higher wind speed
will be needed to achieve the same perfomance.
If the lift or head are reduced, a lower wind speed is needed.
How can the performance be improved?
Windmill water pump performance can be improved four ways:
• Reducing the lift height
• Reducing the required head (the height to which the water must be pumped)
• Siting the windmill water pump where there is a reliable and steady wind
• Maintaining the windmill water pump and keeping it well-lubricated
Lift
What is lift?
Lift is the vertical height between the surface of the water
source and the pump inlet. Any dips and rises in the
pipe between the water source and pump inlet will not affect
the lift. The horizontal distance does not matter.
If the mouth of the intake
pipe is below the surface of the water source, will this
increase the lift?
No. Even though the intake pipe
is submerged in the water, the increased pressure at the
mouth cancels the vertical height difference, so this can
be ignored.
I need to lift water more
than 25 feet. Can I still
use the Ferguson Windmill Water Pump?
Physics says that an ideal water pump at sea level can lift
water no more than 32 feet. For a real world pump,
the lift limit is about 25 feet. If
you need to lift water farther, you should put the windmill
water pump closer to the water source. If this is not
practical, consider using a wind turbine paired with an electrically-powered
submersible pump. We
can help you with both solutions.
I live in the high plains,
about 7000 feet (2100 m) above sea level. Does
this affect the maximum lift?
Yes, at this elevation the maximum practical lift is reduced
to 20 ft. (6.1 m). For other elevations, consult this table:
Elevation |
Maximum Lift |
sea level |
26 ft. |
7.9 m |
1000 ft. (300 m) ASL |
25 ft. |
7.6 m |
2000 ft. (650 m) ASL |
24 ft. |
7.3 m |
3500 ft. (1000 m) ASL |
23 ft. |
7.0 m |
4500 ft. (1400 m) ASL |
22 ft. |
6.7 m |
7000 ft. (2100 m) ASL |
20 ft. |
6.1 m |
10,000 ft. (3000 m) ASL |
18 ft. |
5.5 m |
13,000 ft. (3900 m) ASL |
16 ft. |
4.9 m |
16,000 ft. (4900 m) ASL |
14 ft. |
4.3 m |
Head
What is head?
Hydraulic head (or simply, head) is another word for water pressure,
often expressed in feet. For
the Ferguson Windmill water pump, this is the maximum vertical
height to which the pump can pump water. Horizontal distance
is not a factor. Because the flow rates are low, internal
pipe resistance is minor and does not affect the head.
Siting
Does the windmill
need to be near the water source?
No. It may be more practical to put the windmill some
distance from the water. Perhaps where the wind is more
reliable. Perhaps downhill from the water source.
Applications
Can the wind mill water pump
be used to aerate a pond?
Yes. Water must come in contact with
the air to become aerated.
The larger the surface area of water exposed to the air,
the greater the oxygen uptake. You
can use the windmill to pump water through a spray
nozzle. This
aerates the water as it falls back into the pond. |
