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January/February 1994 Backwoods Home Magazine INDEPENDENT ENERGY
windmill, but the well is protected
The solar-powered silent partner from the wind. A new source of ener-
gy would have to be found.
About this time a friend of ours
By Jim Slater first site he was shown, which hap-
loaned us a solar products catalog.
(with Larry Elliott) pened to be located next to our cistern
Little did we know that so many prod-
installed up the hill from the house, he
hen my wife Jessie and I ucts existed for folks like us who live
W moved to our new place on
the High Desert of Central
Oregon, we knew that a steady, reli-
looked at the dark red rock formation
and said “Don’t look like you will do
any good here. I’ve drilled in this type
before and never had any luck.” He
beyond the grid. After reading the sec-
tion on water pumping and looking at
solar panels and trackers, it all began
to sound good. Since all advertising
able supply of water would be our asked to see something else. At this
prime consideration. With 160 acres should be taken with a grain of salt,
point our options had just dropped by
of dry, parched desert, our first major we decided to talk to others who may
50%. I then told him we had picked
project would have to be a water well. have already had experience with
another area because it was located
We had looked long and hard at the solar pumping. A rancher friend of
near a hillside spring and close to the
lay of the land before we bought it to ours said that he knew people further
junction of two large gullies that
make sure that a well could be drilled east of us who were using a solar
drained hundreds of acres, the only
and pumped without bankrupting us. pump with good results. A rancher
drawback being that it was very
To our west is an area where deep will be the first to tell you if some-
remote and near the top of a steep hill.
wells and dry holes are common. We thing does or doesn’t work. We heard
“Well let's see it,” he said. Our spirits
could not afford to end up with either only positive comments, which was
where lifted when he took a look at
of these. Typically a well in this area what I wanted to hear.
some hard grey rock and told us that if
ends up at 700 to 800 feet and leaves he could set up his rig on this remote
the land owner with a bill of over spot, there would be a good chance of The solution found
$15,000 even if it’s only a dry hole. finding water. Since one of my wife’s A local solar distributor and installer
To the north and south of us steep many talents happened to be dowsing, was next contacted. We told him that
buttes are dotted with small springs it seemed like a good idea to let her we wanted to get a solar pump but
that run cold and clear year round, try her hand in verifying the driller’s needed to make sure we got the right
even during our recent seven-year observation. After a few quick passes, one. We had decided on a DC sub-
drought. We were hoping that this Jessie said, “Drill here.” As it turned mersible with a passive tracker. He
high water table could be found some- out, they were both right. The well asked if we had considered a jack
where on our place. came in at 185 feet and better than 5 pump. We replied that we had, but the
Even if we could find water, the gallons per minute. Not only did this cost was too high for our budget. He
next obstacle that would need to be solve our water problem, but it also said, “I just happen to have a used
overcome would be that the nearest proved we were right to question the jack with a motor and controller I’d
power line was two miles away and, at conventional “wisdom” of the locals like to sell.” After spending the rest of
$6 per foot to get it here, this option who said it couldn’t be done. the day checking out the jack and
would be out of the question. Any doing a lot of arithmetic, we called
energy we would use to pump water Next problem him back and said, “Let's do it.”
would either have to be portable (gas, The main reason for choosing the
diesel, etc.) and easily purchased or Now that our first problem was out
jack pump over the submersible,
we would have to produce it our - of the way, we had to face the prob-
besides the cost, was that should
selves. An AC submersible pump and lem of how to get the water out of the
something go wrong with the motor,
generator was considered first, then a ground and then deliver it many hun-
repairs would be quite easy and rela-
windmill or perhaps a gasoline pow- dreds of feet down to our house and
tively inexpensive. In a jack pump the
ered jack pump. At this stage we had cistern, as well as pasture. Since the
motor is above ground, not in the well.
not even heard of a solar pump. well pump would now be situated 950
A simple belt and pulley connect the
feet up a steep and fairly inaccessible
motor to a gear box. A gas motor
Looking for water hill, we didn’t feel like having to sup-
could be attached if need be, or per-
ply any pump that would need fuel.
Two sites were chosen on our prop- haps a bicycle pulley, although not
Packing a gas can uphill on skis or
erty as likely to have water. A well very practical. Also, by attaching a
snowshoes just did not appeal to us.
driller recommended by a friend was larger motor and more panels, the out-
We gave some thought to using a
called in to look things over. At the
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January/February 1994 Backwoods Home Magazine
put of the pump could be increased in pulls a 7/16" steel rod up and down taken to ensure that all sections would
the future if needed. inside the well pipe. This rod then dri- be self draining each night.
After a few weeks, we had all the ves a piston and cylinder located at the The pipe terminates at an under-
equipment necessary to complete the bottom of the well in an up and down ground 1800 gallon cistern. The cis-
pump installation. The well driller was motion that lifts water to the surface. tern is located about 300 feet from the
called back to help set the pipe and The water is truly “jacked” to the sur- house with a drop of about 50 feet. A
well cylinder, and all went along with face with each stroke. Our well cylin- separate pipe comes out the top of the
only some minor problems. The first der travels about 18" with each stroke cistern to act as an overflow. This
time water began flowing out the dis- and with a 1 7/8" piston delivers over overflow is piped past the house to the
charge pipe we knew we had a winner 1.5 gallons per minute in full sun. barnyard where it fills a stock pond
and that at least our first two problems At some point, we shall increase this and stock tank. We use a system of
had been overcome. production by using a larger cylinder valves to direct this water. A 5-foot
and motor, and by adding two extra piece of 12-inch water main fits
How it works solar panels. The tracker we pur - around both valves and stands verti-
chased had room for a total of eight cally above them. The top is plugged
For all of you who may not be panels, so we will have room for them with foamboard and covered with a
familiar with the components that without any modifications. This is piece of plywood. This valve box is
make up a complete solar pumping something to keep in mind if you may insulated from freezing by filling large
system and have only a little knowl- be looking to do as we have done. plastic garbage sacks with fiberglass
edge of how it works, a brief descrip- The entire pump assembly is housed insulation. Using duct tape to hold it
tion is in order. in a small A-frame shed that serves to together, I rolled up a two and one
In our system, six used Arco (now keep ice, rain and snow, as well as half foot section of unfaced insulation
Seimens) M-51 photovoltaic panels critters, off the pump. Since we have to about a 12-inch diameter coil and
are wired in series to produce the volt- cattle roaming about our area, a placed it in the garbage sack. This
age necessary to drive the motor. barbed wire fence was built around insulates from ground level to the top
These panels are mounted on a the pump and the solar tracker to pre- of the valves.
Zomeworks passive tracker (requires vent damage. Even if you don’t have Since our system is gravity fed, our
no electric motors or external power cattle, deer can do a lot of damage if water pressure at the house is about 22
source) which orients the panels they decide to use your tracker as a P.S.I. This is somewhat lower than
toward the sun as it travels across the scratching post. standard city water pressure, but
sky. After we were assured we would serves us very well and is more than
The electric power produced by the have a steady supply of pure water, enough to allow use of a tankless
panels flows to a controller which, in the hardest phase of the entire project water heater. We have kept all of our
our system, is a 600-watt Australian had to to tackled. We had to dig a pipe sizes a little larger than required
Energy Concepts Maximizer. This trench and lay pipe the entire distance to lower the friction and give better
power is then fed to a 1/3 hp perma- (over 1000 feet) to our house and cis- water delivery.
nent magnet motor that drives a 60:1 tern. Instead of simply digging trench- We had one of the coldest winters
ratio gear box through a belt and pul- es and laying pipe, we decided to on record this year, and no part of the
ley arrangement that also serves to carefully design the entire system to water system froze. The jackpump
further increase the ratio between give us maximum water to several dif- output was enough to keep us and our
motor and gear box rpm. This wide ferent sites and do it without having livestock well supplied with water
gear ratio serves to keep the pumping our bitter cold winters freeze pipes even though we hardly saw the sun for
action slow and very powerful due to and leave us without water. the two months of December and
the high torque generated. Our water project became a real test January. We are very happy with our
The rotary motion of the gear box is of our commitment to living off the water system. Last summer we were
then converted to reciprocating up and grid and on an isolated ranch. Our blessed with a beautiful vegetable gar-
down motion using an eccentric, in a pipeline had to be laid in a ditch that den. Carrots, potatoes, bush beans,
manner somewhat similar to the dropped down a steep slope for over corn, strawberries, pumpkins, onions,
method used to drive steam locomo- 950 feet and had to be dug through a cukes and more all grown with water
tive wheels. This up and down motion lot of rock. 250 feet of this ditch had pumped by the sun and on land that,
is transmitted to a cable and walking to be dug and backfilled by hand. until then, was dry and brown and
beam (very similar to oil field pumps After all the backbreaking digging stripped of moisture. The horses now
that look like giant prehistoric birds was done, 1 1/4" PVC pipe was laid drink cold, clear water on the hottest
bobbing their heads up and down) that down the entire length. Care was
35
January/February 1994 Backwoods Home Magazine
days of summer and splash in their
own pond to cool themselves.
We did a lot of planning and hard
work to accomplish these things, but it
has all been worth it.
The Maximizer, or LCB, used in this
system is without a doubt the most
important component of all. This con-
troller can be best described as an
electronic gearshift. It converts amps
to volts or vice versa. In our system,
six photovoltaic panels, each produc-
ing 2.3 amps at about 17.3 volts, are
wired in series (positive to negative,
etc.) to give a total of 2.3 amps
(remember, in series circuits only the
voltage adds) at about 104 volts. In
very bright sun this voltage and cur-
rent can be even higher.
Since our motor requires around 90
volts to operate at full speed, the
Maximizer converts (using switching
technology found in computers) the
excess voltage to current to supply the
three amps needed by the motor. This
allows the pump to operate at maxi-
mum efficiency even in low sun con-
ditions. On overcast days or when a
cloud passes overhead the voltage of
the panels stays around 96 volts, but
the amps decrease. In this condition
the motor would normally stop. The
Maximizer now “shifts gears” and
supplies additional amps at a lower
voltage and keeps the pump running.
The only time our pump stops is in
total darkness or in groundfog. D
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