diy solar

diy solar

Anyone dealt with rpssolar?

drjenk

New Member
Joined
Jul 22, 2022
Messages
5
Hi,
We just bought into some property with a well already in place, and my first order of business is getting a pump and power it by solar. I also want to eventually power everything on the property with solar, off-grid, but that is a ways in the future. We want to build a small cabin, and I want to build a garage in the near term also, all which will be off grid, powered by the inverter.
But the very near term need is water from the well so we can at least park our RV there for an extended period of time while working on the above.

So I came across this:

My only hesitation, is that the power unit seems to include everything, the inverter, converter, solar controller, transfer switch etc. Single point of failure. I see why they're doing it that way, they make it very easy for the end user to install. But I've got a rough diagram of what I want to do also, and I'm thinking of just doing everything myself and buying everything separate. My only experience with solar is my RV the last couple of years. I managed to install an inverter, and a new converter without blowing anything up, I do have an engineering background. But I do love simplicity and the fact it is just delivered and ready to install. Would appreciate some feedback on this company.

Also I'd appreciate some feedback on a diagram I made, that represents a block diagram of what I'm thinking. I haven't researched brands, cost etc at all yet. I know type of battery will heavily influence overall cost, if I buy into a large quantity initially. And I want to make sure I get a future proof capacity of inverter, as I can always add panels and battery later as needed, hence the 12kW inverter.
 

Attachments

  • Solar Concept.png
    Solar Concept.png
    135.4 KB · Views: 11
I bought a pump and controller from RPS and powered the pump with two 100W panels from a different source (no batteries, so pumping only when the sun hit panels). Installation was easy - good instructions from RPS (written and videos); only lowered the pump to about 40’, so no winch needed. Based on my experience, I give a thumbs up to RPS equipment and customer service.
 
I bought a 1.5hp irrigation pump kit from RPS a year ago. The kit came with everything I needed except for panel mounting materials and wire for the run from the controller to the pump. Included instructions were excellent, as was the assistance i got from RPS' sales and support staff. Their kits use top grade equipment. So far the system has performed flawlessly.

I thought about sourcing the components myself and saving some money but I wasn't sure I could figure it all out.
 
Sounds good. Still going to research as I probably won't do the full deal until next spring, so many solar companies.
 
I picked up a Nemo submersible pump for a solar project https://www.nemopumps.com/. They take a standard flowjet pump and make it submersible. They assemble them in Maine. Hard to beat the price and my guess is it will run a lot longer than the Chi com crap that is in the same price range. I pump from a well into an IBC tank elevated on a pile of firewood. There is float switch on top of the tank that turns the power on an off with three 60 watt panels. No battery and no controls except the float switch. A cheap way to get water. Obviously you need to size the panels to the pump discharge head.
 
No direct experience with RPS but I can say that the Grundfos SQF that can be powered directly by solar or AC power. It may be way more pump than you need though. Their SQ is AC powered only and lower cost. The nice thing about either one of those pumps most inverters or generators can power them because they slowly come up to full speed. No big initial surge.

Grundfos SQ video on YouTube.
 
I picked up a Nemo submersible pump for a solar project https://www.nemopumps.com/. They take a standard flowjet pump and make it submersible. They assemble them in Maine. Hard to beat the price and my guess is it will run a lot longer than the Chi com crap that is in the same price range. I pump from a well into an IBC tank elevated on a pile of firewood. There is float switch on top of the tank that turns the power on an off with three 60 watt panels. No battery and no controls except the float switch. A cheap way to get water. Obviously you need to size the panels to the pump discharge head.
That looks like a neat pump if your well isn't too deep. Not much flow but if you combine that with a surface storage tank and pressure pump you can get into an off grid water pumping system for not much money. Thanks for sharing.
 
I have no experience with RPSolar.

Well pumps are a difficult area to power. Due the fact they sit down in the ground (for every foot of depth water pressure rises .434psi) and are always pumping under load they have higher requirements for surge and running amps than practically any other motor driven device (air compressors are similar but unloaders can help). If you pump to a unpressurized tank at the surface you can reduce the demand a fair bit but not eliminate completely.

So simply buying a generic solar setup might not fit your particular circumstances. You will want to arm yourself with your pumps actual current demands during operation.
 
230 feet (100 psi) of discharge head is not that shabby for most applications. The well I pump from is surface well with the DC pump is about 17 feet deep, right next to it is low yield deep well that is 320 feet deep but the resting water level is 40 feet. The reason for the well depth is its yield is only 1.5 GPM. Therefore, the pump has to be quite deep for reserve capacity. AC pumps can put out a lot of water but they are not efficient. DC well installations usually optimize efficiency by pumping small volumes continuously to a ground level storage tank and then water is pumped out as needed to supply specific tasks
 
230 feet (100 psi) of discharge head is not that shabby for most applications.
It's almost useless in most applications I see. Obviously it's very site dependent.

FWIW, my standard 1HP well pump sits at 425' with a static of 250'. It pumps all the water a standard house of three needs for an average of less than 750 watt hours per day. Give or take all I need is one 300 watt solar panel for all of my water pumping. For most applications efficiency has nothing to do with pump choice.

AC pumps can put out a lot of water but they are not efficient. DC well installations usually optimize efficiency by pumping small volumes continuously to a ground level storage tank and then water is pumped out as needed to supply specific tasks
That's an interesting comment which reminds me that I've been meaning to do that math as I don't like being just another guy with an opinion.

From what I've seen efficiency has nothing to do with AC vs DC. Generally speaking positive displacement pumps are more efficient than centrifugal and most positive displacement pumps that you see in this arena are DC but they could just as easily be AC.

Now if you're trying to go off-grid without an inverter and are willing to trade a ton of convenience and capacity then that's an entirely different discussion.

The Nemo (DC positive displacement) ~75 watts to pump 1.57 GPM at a 93' of head for ~48 watts of power per gallon of pumping.

I randomly chose a Grundfos 16 SQF-10 (AC or DC centrifugal) looks like it needs ~380 watts to pump 8GPM at a 100' of head for ~48 watts of power per gallon of pumping.

Well... how about that? That surprised me. No difference in efficiency for that one comparison.

Who knows what happens in other spot in the pump curve and in regards to other brands of pumps.

Please don't read anything I typed as being argumentative. I enjoy the dialogue as I'm always trying to learn. Cheers!

1658925927087.png

1658926313452.png
 
I like the discussion ...

I'm looking for a replacement to my deep well pump. It's been in the casing for 20 years and is due for a failure. It's 220V ac ... and im trying to weigh my options

I could do 12v, 24v or 48v ... my lifepo4 8.7kwh battery isn't exactly permanently set to a voltage.


I still need to get a split phase inverter and install a 10420an ...
 
Last edited:
i have 2 rps systems on remote pasture wells for livestock, i originally bought them because they were plug and play systems and would be easy for a novice. the systems have been great and the support is out of this world. the oldest system has been in for about 6 years or so with only one hiccup. was checking tanks and noticed they were low, found the controller in standby mode and could not get it to work, of course this was a saturday afternoon. called the support number anyway, figured maybe i would hear from them sometime monday, and started hauling water, early sunday morning an engineer called me back and was able to trouble shoot the system, we got it overrode and pumping and they sent me the replacement parts overnight, no charge for anything. if your well is good, these things pump a lot of water. mine is set to turn on as soon as the controller sees enough juice from the panels and off when it is dark. they do have batteries that can be added to the system but my system fills a 3 thousand gallon tank in a few hours so with that much water storage, i have never need to pump at night.
 
I'm looking for a replacement to my deep well pump. It's been in the casing for 20 years and is due for a failure. It's 220V ac ... and im trying to weigh my options
Same here with a 20 year old pump. My old low frequency Trace SW4048 inverters run it just fine but they are 23 year old. I'm on borrowed time with both. I'll be going with a Grundfos SQ for a variety of reasons. Take a look at them.
 
Maybe I had too much time on my hands today but have been posting a lot on other threads about water solutions. I have tried just about every pump on the market over the years getting water to my cattle and there is a tool for every job for sure. Cattle watering I think is easier (maybe more stressful) then other as I really only need to fill tanks during the day so I get to skip traditional battery/inverter combos and startup current. My most common setup is a direct driven solar pump, controller on the surface (I always recommend this as pulling it sucks and I'd rather work on the controller without pulling the pump. You've got to spend more $1000-2000 usually to get a good one that doesnt have a brushed motor in the well and a good controler up top.. once you have that and the solar panels feeding into it you just have to add panels and tanks when you add cows. I have been growing the herd and so its been good for me. Water pressure for houses and irrigation isnt as much my specialty. I also don't like to rep any one company as most have a variety of different products, surface, sump, pressure and other stuff and some of them do multiple and some are better than others. I will say that I would alwsy recommend spending a bit more on the well pumps as they suck to pull up and I usually need to grab someone to help (bad back) and I am compelled to post here as I have been saved by RPS in the past as their engineers helped me find problmens over the phone in my setup without pulling the pump (on a pump of theirs and one that wasnt theirs even which was really nice of them and I probably shouldnt mention that here but alas) -- often its sensors, solar connectors or lightning. GROUND your controllers! Any kind you get! Learned that the hard way as I mount them on windmills as big antennas asking for lightning! Honestly I'd recommend calling a few places in the US and explaining your setup and see who has a good solution. I always appreciated someone to talk it through with and plan it out for my first 5 or 10 of these.
 
Back
Top