I can't find much via google on serious 12 volt pond pumps. Are there
any r.p.m readers using one, or know of one that can pump suitable
volumes for use in a 5000+ litre pond?

I'm interested to know the power requirements and feasibility of running
from a car batter charged by photovoltaic panels. The price of solar
panels seems to be dropping all the time, and with energy costs going up
it might be worth looking into.

David

On Fri, 11 Jul 2008 16:21:05 EDT, DavidM
wrote:

I can't find much via google on serious 12 volt pond pumps. Are there
any r.p.m readers using one, or know of one that can pump suitable
volumes for use in a 5000+ litre pond?

I'm interested to know the power requirements and feasibility of running
from a car batter charged by photovoltaic panels. The price of solar
panels seems to be dropping all the time, and with energy costs going up
it might be worth looking into.

David

I'm hoping you'll find an answer here. I know my son is trying to figure
out how to power my motion sprinklers via solar. At least where the
batteries are charged during the day, and will run all night. ~ jan
------------
Zone 7a, SE Washington State
Ponds: www.jjspond.us

How about running a conventional 120v pond pump off of an inverter powered
by the 12v battery.


"DavidM" wrote in message
...
I can't find much via google on serious 12 volt pond pumps. Are there any
r.p.m readers using one, or know of one that can pump suitable volumes for
use in a 5000+ litre pond?

I'm interested to know the power requirements and feasibility of running
from a car batter charged by photovoltaic panels. The price of solar
panels seems to be dropping all the time, and with energy costs going up
it might be worth looking into.

David

What about using a inverter to power a 120v pump. Solar cells charge the car
battery, inverter changes 12VDC to 120 VAC to run the pump. Simple and you
can use common pond pumps.
Paul

"DavidM" wrote in message
...
I can't find much via google on serious 12 volt pond pumps. Are there any
r.p.m readers using one, or know of one that can pump suitable volumes for
use in a 5000+ litre pond?

I'm interested to know the power requirements and feasibility of running
from a car batter charged by photovoltaic panels. The price of solar
panels seems to be dropping all the time, and with energy costs going up
it might be worth looking into.

David

On Sat, 12 Jul 2008 21:58:32 EDT, ~ jan wrote:

On Fri, 11 Jul 2008 16:21:05 EDT, DavidM
wrote:

I can't find much via google on serious 12 volt pond pumps. Are there
any r.p.m readers using one, or know of one that can pump suitable
volumes for use in a 5000+ litre pond?

I'm interested to know the power requirements and feasibility of running
from a car batter charged by photovoltaic panels. The price of solar
panels seems to be dropping all the time, and with energy costs going up
it might be worth looking into.

David

I'm hoping you'll find an answer here. I know my son is trying to figure
out how to power my motion sprinklers via solar. At least where the
batteries are charged during the day, and will run all night. ~ jan

There are several things you can do. Depending on the power you
want, there are oodles of solar possibilities. Virtually any pump
that runs on AC can also be made to run on DC, if you are willing to
spend the bucks. You may find that photovoltaic cells are a rather
poor investment as you go farther north.

I regularly run a bunch of stuff, both AC and DC, off photovoltaic
cells. It costs a *lot* up front, but it is virtually maintenance
free and doesn't cost a thing once you get it set up.

Galen Hekhuis

I wonder if you can get enough power from a photo cell without paying
an arm and a leg?

How powerful is your pump?

Jim

"Phyllis and Jim" wrote in message
...
I wonder if you can get enough power from a photo cell without paying
an arm and a leg?

How powerful is your pump?

Jim


Kinda depends on how much arms and legs go for in your neck of the woods.
I've a Sequence pump that uses about 120 watts. A 400 watt inverter ($30)
would easily run it. Car battery, maybe $75 or so. Now here's where the body
parts come in. On ebay, 123 watt solar panels go for $660 each and I'd need
two of them, figuring that the sun only shines 1/2 the time, but the pump
runs 24/7. Maybe 3 would be better to allow for cloudy days and system
losses. Throw in a charging regulator, and we're in the 2 kilo-dollar
neighborhood. That's more than arms and legs go for around here. It doesn't
sound feasible for anything larger than say a whiskey barrel size water
feature.
Paul

Phyllis and Jim wrote:
I wonder if you can get enough power from a photo cell without paying
an arm and a leg?

How powerful is your pump?

Jim


My current pond pump is 50 watts. An inverter runs at 90% efficiency
according to the manufactures, so probably more like 80%, that bumps it
up to ~65 watts. I'm guessing even 50% output from a solar panel is
optimistic (% of total output, not efficiency) in Southern UK, even
though East Anglia is technically a desert
Looking at 120 watt solar panels make me think that it's not such a
great idea. They are in the £700 region here in the UK, that's without
batteries, charging circuits and the inverter.

How about gas fired steam pump?

~ jan wrote:

On Fri, 11 Jul 2008 16:21:05 EDT, DavidM
wrote:

I can't find much via google on serious 12 volt pond pumps. Are there
any r.p.m readers using one, or know of one that can pump suitable
volumes for use in a 5000+ litre pond?

I'm interested to know the power requirements and feasibility of running
from a car batter charged by photovoltaic panels. The price of solar
panels seems to be dropping all the time, and with energy costs going up
it might be worth looking into.

I'm hoping you'll find an answer here. I know my son is trying to figure
out how to power my motion sprinklers via solar. At least where the
batteries are charged during the day, and will run all night. ~ jan

First, don't use a car battery. Sure they're cheap, but they won't last
long.

But really, I don't think such a beast exists. I bought about the most
efficient pump I could get, for my 5000 _gallon_ pond, and it drew ~215W.
Let's just pretend you could use something a quarter the size for 5000
liters (probably you'd need bigger). 50W 24 hours per day is more power
than my entire solar powered home uses! That's 1.2KwH daily, and I use
about 1KwH for my house. I run 800W of solar panels to get that.
Admittedly, I need to account for short winter days, and foggy Springs, and
since you'll likely only need it in the summer, and may have much more
sunlight, you might conceivably get by with only about 400W.
--
derek

Paul wrote:

How about running a conventional 120v pond pump off of an inverter powered
by the 12v battery.

You lose up to 15% of your power to the conversion, and DC pumps are more
efficient in the first place.
--
derek

Paul wrote:

Kinda depends on how much arms and legs go for in your neck of the woods.
I've a Sequence pump that uses about 120 watts. A 400 watt inverter ($30)
would easily run it. Car battery, maybe $75 or so. Now here's where the
body parts come in. On ebay, 123 watt solar panels go for $660 each and
I'd need two of them, figuring that the sun only shines 1/2 the time,

The sun doesn't shine 1/2 the time. You'd be hard-pressed to find anywhere
in North America where the sun shines on average 7 hours per day (in
summer - I assume we don't need to worry about winter).

but
the pump runs 24/7. Maybe 3 would be better to allow for cloudy days and
system losses.

otoh, three 123W panels is pretty close to my back of the envelope
calculation :-)

I can get them for much less than $660, but they'll cost at least that by
the time shipping is calculated. They're big and bulky, and they only ship
FedEx or UPS Ground in most cases.

Throw in a charging regulator,

actually, they're available under $50

and we're in the 2
kilo-dollar neighborhood. That's more than arms and legs go for around
here. It doesn't sound feasible for anything larger than say a whiskey
barrel size water feature.
Paul

--
derek

On Mon, 14 Jul 2008 08:13:20 EDT, "Paul" wrote:


"Phyllis and Jim" wrote in message
...
I wonder if you can get enough power from a photo cell without paying
an arm and a leg?

How powerful is your pump?

Jim


Kinda depends on how much arms and legs go for in your neck of the woods.
I've a Sequence pump that uses about 120 watts. A 400 watt inverter ($30)
would easily run it. Car battery, maybe $75 or so.

Except a car battery won't work. Batteries found in cars are
typically designed to provide a high current for a relatively brief
time (cranking) whereas what is needed is a lower current for a
relatively long time (like a golf cart). At 120 watts at 120v that's
1 amp, at 12 volts that will be a 10a draw. Most car batteries can't
handle that, as a matter of fact, most "deep cycle" type batteries
won't handle that. What will probably be needed is a several
batteries in parallel to provide that much current overnight.

Now here's where the body
parts come in. On ebay, 123 watt solar panels go for $660 each and I'd need
two of them, figuring that the sun only shines 1/2 the time, but the pump
runs 24/7. Maybe 3 would be better to allow for cloudy days and system
losses.

You'd need two of them even if optimal conditions were present 100% of
the time. Remember, the batteries have to be recharged from the
previous night's use while supplying power to the pump at the same
time during the day. Furthermore, even on bright, cloudless, sunny
days the photovoltaic cells are only going to provide full power for
just a few hours at best. There will be some output during morning
and late afternoon, but nowhere near the 120 watts needed. 3 panels
sounds quite optimistic.

Throw in a charging regulator,

This will be essential, and matching the regulator to the type of
batteries you have (so as not to overcharge or something harmful to
the life of the batteries) is critical, if battery life is to be
maximized.

and we're in the 2 kilo-dollar
neighborhood.

Probably a lot more.

That's more than arms and legs go for around here. It doesn't
sound feasible for anything larger than say a whiskey barrel size water
feature.
Paul

You have to have a real interest in photovoltaics right now to make
this work. It is very expensive up front, and most folks cannot
justify the expense on simply economics. Granted, there are
exceptions where this is an economic alternative to being "on the
grid," but for most folks getting power from the electric company is
still the way to go, high energy prices notwithstanding.

Galen Hekhuis

"Derek Broughton" wrote in message
...
Paul wrote:

Kinda depends on how much arms and legs go for in your neck of the woods.
I've a Sequence pump that uses about 120 watts. A 400 watt inverter ($30)
would easily run it. Car battery, maybe $75 or so. Now here's where the
body parts come in. On ebay, 123 watt solar panels go for $660 each and
I'd need two of them, figuring that the sun only shines 1/2 the time,

The sun doesn't shine 1/2 the time. You'd be hard-pressed to find
anywhere
in North America where the sun shines on average 7 hours per day (in
summer - I assume we don't need to worry about winter).

but
the pump runs 24/7. Maybe 3 would be better to allow for cloudy days and
system losses.

otoh, three 123W panels is pretty close to my back of the envelope
calculation :-)

I can get them for much less than $660, but they'll cost at least that by
the time shipping is calculated. They're big and bulky, and they only
ship
FedEx or UPS Ground in most cases.

Throw in a charging regulator,

actually, they're available under $50

and we're in the 2
kilo-dollar neighborhood. That's more than arms and legs go for around
here. It doesn't sound feasible for anything larger than say a whiskey
barrel size water feature.
Paul

--
derek


Actually, my whole point here was that the idea of powering a pond pump with
PV cells would be cost prohibitive for all but the _money is no object_
ponder.
Paul

Galen Hekhuis wrote:
On Mon, 14 Jul 2008 08:13:20 EDT, "Paul" wrote:


"Phyllis and Jim" wrote in message
...

snippy
You have to have a real interest in photovoltaics right now to make
this work. It is very expensive up front, and most folks cannot
justify the expense on simply economics. Granted, there are
exceptions where this is an economic alternative to being "on the
grid," but for most folks getting power from the electric company is
still the way to go, high energy prices notwithstanding.

Galen Hekhuis

How about part PV, part wind power?
http://www.unlimited-power.co.uk/Aer...enerators.html
For instance. When it's sunny, it's rarely very windy. You get wind in poor
weather.............all night too
--
Pete C
London UK

On Mon, 14 Jul 2008 14:49:00 EDT, "Pete C"
wrote:

Galen Hekhuis wrote:
On Mon, 14 Jul 2008 08:13:20 EDT, "Paul" wrote:


"Phyllis and Jim" wrote in message
...

snippy
You have to have a real interest in photovoltaics right now to make
this work. It is very expensive up front, and most folks cannot
justify the expense on simply economics. Granted, there are
exceptions where this is an economic alternative to being "on the
grid," but for most folks getting power from the electric company is
still the way to go, high energy prices notwithstanding.

Galen Hekhuis

How about part PV, part wind power?
http://www.unlimited-power.co.uk/Aer...enerators.html
For instance. When it's sunny, it's rarely very windy. You get wind in poor
weather.............all night too

Wind power is a real alternative. There have been substantial
advances made both in power generation and design of the structure.
Here in Florida we too often have the problem of too much wind, so
wind power isn't as popular here as in other places. My wife and I
lived in a section of Maui (Hawaii) that had no utilities (no phones,
no electricity, no water, etc.) but a pretty good supply of wind and
almost everybody had a windmill of some type. Of course, the
maintenance is a bit higher for wind power. The ultimate would be to
have your own little hydroelectric plant. With today's technology
they exist in kilowatt sizes now, and what with sealed bearings and
all they can be almost maintenance-free. But unlike water power, wind
power is available to a lot more people, and at much less expense than
a photovoltaic array.

Galen Hekhuis