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That depends on your location, water source and time of year usage.
One hundred cattle can drink 2,000+ gallons of water per day which can
be very cost effective to provide from a shallow source of water
(£100') in the summer months. Please fill out our water pumping
questionnaire and send it to us and we can put together an itemized
system quote for you.
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There are really only two basic types of solar pumps; positive
displacement and centrifugal and these can both be subdivided into
surface mount and submersible categories. Your water source will dictate
whether you need to use a surface mount or submersible pump while your
daily volume requirement and total dynamic head (TDH) will determine if
you need a positive displacement pump or centrifugal pump. In general,
positive displacement pumps (diaphragm, piston, helical rotor, etc.) are
best used where the TDH is high and the daily volume requirement is low.
Positive displacement pumps usually require less power to operate than a
centrifugal pump and they will produce some water even in cloudy
conditions where a centrifugal pump might not. Centrifugal pumps are
good in situations where the TDH is low and the daily volume requirement
is high. One of the disadvantages of a centrifugal pump is that it has
to operate at a high enough rpm to push the water all the way out of the
well. If it is cloudy and the solar array is not producing enough power,
the pump/motor may be turning but not fast enough to do this. Using a
tracker is highly recommended with a centrifugal pump since it increases
the solar array's power output over a longer period of time which
increases your daily volume of water delivered. We carry pumps from the
following manufacturers: Lorentz,
Dankoff, Grundfos,
Shurflo, Sunmotor
and Sun Pumps. Click on each name for information about the different
models that they have to offer.
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That depends on many factors all of which are addressed in our
"Water Pumping Questionnaire". Please fill it out as best you
can and fax/e-mail it to us and we will gladly recommend which pumping
system will best suit your needs.
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Head is measured in feet/meters or psi and it is a term for the
distance that a pump has to push the water from your source to your
tank. It may seem odd to be able to list head in terms of pressure or
distance, but keep in mind that a column of water 2.31' tall produces 1
psi at the bottom of that column so there is a correlation between
distance and pressure. The greater the vertical distance is in between
the water source and the tank, the harder the pump has to work to get
the water there. Static head is the simple measurement from the surface
of the water (when the pump is not running) to the tank. Dynamic head
takes into account the amount the water level in the well drops when the
pump is running plus the friction loss in the discharge pipe run. Total
Dynamic Head is the sum of the static head and dynamic head.
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Yes, but you are limited as to how far you can pull water up. The
theoretical maximum is 33' if you were able to pull a perfect vacuum at
sea level. However, few pumping systems are setup at sea level and no
pump on the market is able to develop a perfect vacuum on its inlet
side. A good rule-of-thumb to go by is don't assume that you can
reliably pull water out a well where the static water level is lower
than 10'.
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The smallest submersible solar pump that we have is the 3"
diameter Grundfos SQFlex so a 2" casing presents a bit of a
challenge. If the water is within 10' of the surface, we may be able to
pull the water out with a surface pump. Otherwise you would have to
consider using a jack pump which looks and works just like an oil well
you see in various parts of the country. These systems are fairly
expensive and complex with their sucker rods, cylinders stroke length so
give us a call and we can help you design this type of system.
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The answer to this question depends on your application (domestic use
or stock watering), the daily volume of water that you need and what
time of year you plan to use the pumping system. For most livestock
water pumping applications where the highest daily volume of water is
usually needed during the summer, a tracker is highly recommended since
it can increase your daily water production by as much as 40% as
compared to the same array on a fixed mount. In the winter time, a
tracker only increases your daily water production by 5-10%. If your
daily water volume requirement is low or you are setting a solar pumping
system up for winter time use, then a fixed mount structure is probably
the best choice. There are several manufacturers of tracking mount
structures, but they can all be divided into two categories: active and
passive. Active trackers use sensors, actuators and motors to follow the
sun from east-to-west while passive trackers use the heat of the sun on
two sealed freon containers (one on each side of the tracker connected
with a tube) to do the same thing. Passive trackers are simple and
reliable, but they aren't as accurate in aiming at the sun as active
trackers and they can be blown off course in high winds. On the other
hand, active trackers are more trouble prone and more expensive than
their passive counterparts. Give us a call if you want to look into
trackers in more detail.
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DON'T USE BATTERIES! The only reason I would ever consider using
batteries in a solar pumping system is if you have a very low volume
producing water source (well/spring) and you need to pump as much water
out of it as you can each day. Otherwise, there are several reasons to
avoid batteries in a pumping system:
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Using batteries in a solar pumping system lowers the efficiency as
compared to going solar direct since it usually lowers the operating
voltage of the pump which lowers the operating speed and flow rate
of the pump.
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Adding batteries to a pumping system costs more money for the
batteries themselves plus a required charge controller, battery
enclosure and additional disconnects and wiring.
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Batteries require care and maintenance that isn't always possible
in a remote location.
-
Batteries performance level and expected lifetime are closely
connected with the temperatures that they are subjected to. If
batteries are undercharged and subjected to freezing temperatures
they could be damaged. If batteries are overcharged and subjected to
high temperatures their lifetime will be shortened dramatically.
Care must be taken to shield batteries in a remote location from
temperature extremes.
You're better off all the way around if you simply go with a solar
pumping system that is designed to give you all the water you need
during the daylight hours without having to resort to using batteries.
Store water in a tank instead of energy in a battery! For a livestock
watering system or gravity fed domestic application, we recommend that
you use a storage tank that can hold a minimum of 3 days worth of water.
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Maybe. Keep in mind that 1 psi = 2.31 feet of head so pressurizing a
tank up to 50 psi adds about 115' of head that the pump must push
against so be sure that your pump can handle it. I would not recommend
using a diaphragm pump for this application because you run the risk of
rupturing the diaphragm if your pressure switch malfunctions. Another
reason not to use a solar direct pump to pressurize a tank is that your
tank might get low in the early morning or late evening when there isn't
enough sunlight for the pump to operate. Pressurizing a tank is best
left to a separate booster pump or an AC centrifugal submersible pump
running off of your inverter/battery bank, generator or utility power.
Better yet, pump to an elevated tank and gravity feed down to your home
or wherever you need the water.
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Yes, but how cost effective this will be depends on your location
(i.e. average wind speed), the daily volume of water you need and what
season(s) of the year you need the water. If you have a very windy site
and you are looking to provide water for a winter pasture, then a wind
powered pumping system makes sense. In general the available wind power
is highest in the winter and a solar array's power output is highest in
summer. The two power sources compliment each other very well seasonally
so for the best year round pumping system it could very cost effective
to setup a hybrid solar/wind pumping system using one of the new
Grundfos SQFlex pumps with a Whisper H80 wind turbine. Keep in mind that
wind turbines have moving parts which are subject to wear and tear and
require maintenance so a wind powered pumping system may not be as
reliable as solar.
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The proper size wire to use in between your solar array and/or wind
turbine and the pump depends on the voltage and amperage of your power
source and the distance you need to run the wire. The size of the pump's
discharge pipe depends on what type of pipe you plan to use (steel or
PVC), the distance from pump to tank and the gpm flowrate that the pump
will produce. The smaller the pipe is the higher the friction loss which
makes your pump work harder to produce less water. We have several
charts available to determine the best wire and pipe sizes to use for
your pumping application so just give us a call and we'll design it for
you.
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That depends on how cold it gets at your site, if your tank is
insulated/bermed and how you plan to keep your tank from freezing.
Heating elements consume a lot of power to keep water from freezing
which would require a large and expensive solar array to operate. There
are bubbler system on the market that simply circulate the warmer water
from the bottom to the top of the tank and those are much more efficient
than a heating element. In very cold climates it is best to install a
cover on your tank that leaves only a small portion of the water exposed
and then berm your tank all the way around and on top of the cover.
There are other more expensive and complicated methods of taping into
the warm earth temperatures below the tank as well as insulating the
tank and only providing water to the livestock when they come to the
tank to drink so give us a call and we can direct you to companies that
provide those products .
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Yes if you design it that way. Most solar pumping systems utilize a
controller that among other things will accept the input from a float
switch in your tank which tells the pump when to start and stop. Some of
the other functions of pump controllers are low water cut-off, lightning
protection and load matching through the use of maximum power point
tracking from the solar array.
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