Needing Help with Components Needed for Off Grid 48volt Solar+Wind system

[zoneblue]

Ok thats good news on the inverter. It was one of my earliest lessons, that for off grid  inverters you must go quality, UL listed, and heavy. Youtube is just full of bad reviews of the aims and similar inverters. They have tiny inductors, hence low surge capability. You want one thats a struggle to lift. These ones run at low frequencys,  use large toroids, make a humming sound, and have awsome surge.

All of the big 3 brands have inbuilt chargers that will allow you to charge with your genset, that isnt a factor at all. Some of the them, the XW, the GFX line, and i think one of the magnums, will also do gen support, which allows you to run both the gen and the inverter at the same time, and they both share the load. Might be a solution for your big draw pump maybe.

For your loads, what you need to do, is take your english description above and turn it into a spreadsheet. This is the very first step, before any hardware discussion. I KNOW its difficult, and i know people resist doing it, but its time well spent and the payback is a system that meets expectation.

Also find the best source of insolation data you can for your area. mainland US have pvwatts which has a good resolution, locatlity wise. Id be deisgnng a solar system first, then after considerable research adding the wind on later.  Wind works where: you have measurably higher than average wind resource. (places people tend not to live).; where you have a proper tower to get above the ground turbulence, (eg 100ft not pole); where the turbine itself is generally more expensive, enthusiast grade ie 5K; and where you have a mechanical bent, are willing to drop the tower annually for service. As you can see its a lot of ifs, and solar is just much easier. and cheaper.

Then as you say much of the battle is getting to know the RE specific brands. People try to muddle along using locally available  marine/automotive parts , but avoid this approach like the plague. Hang around here/naws a bit and youll quiclkly see that there are ddicated components specially engineered for the unique stresses of high current and sometimes high voltage DC current. And theyre easy to get shipped and the price is pretty reasonable all things factored.

Start with the loads, mate.

[vtmaps]

Warreng,

Many off-grid systems have a defining load... a load that the entire system is designed around.  In your case it may be the well pump. 

Give some thought to how much extra that pump will cost you when you design the system.   If not for the pump, what would your power system cost?   Other than the pump, do you need 240 split phase power?

If you are planning to run a machine shop, welder, or other major draws, then your system will be large enough to handle the pump.... otherwise you are supersizing the entire system for the pump.  If that is the case, it may be more cost effective to invest in a solar-direct pump.  There are a few options... they are expensive, but very often they are less expensive (long term and/or upfront) than what you are thinking of.  It is wise of you to separate your well pump and storage tank from your house pressure system... that makes a solar direct system more feasable.

I made a decision when I designed my system to run a generator for the occasional large loads... I need a generator anyway... so my solar power system is not designed to run a floor sander, or support a carpentry crew with air compressors and table saws running at the same time.

I look forward to seeing you over at NAWS...

--vtMaps

[Vic]

Hi warren ...,

Couple of things;

First,  my reference to the PV modules at the Missouri company was just trying to note that the description was inaccurate.     When you get down to knowing just how much PV power that you need,  and what your battery voltage is,  then the decision on how the PV strings need to be configured will become clear.  At that point,  the  voltage of each PV will become clear.   Either the standard GT type PV with 30 -ish Vmp  or perhaps a different one.

As zoneblue noted there is the pvwatts and pvwatts2 calculators from the NREL which help to determine the amount solar insolation you should be able to expect:
http://rredc.nrel.gov/solar/calculators/pvwatts/version1/

Here is a link to the latest version of pvwatts:
http://pvwatts.nrel.gov/

More later,  and YES,  hope to see you at the wind-sun Forum soon.
Vic

[dgd]

#2 -Solar Panels - 10 (qty) 230 Watt 24 Volt Polycrystalline
Product Link: http://goo.gl/qvJmHm

Specs:
Nominal Maximum Output - 230 Watts
Nominal Open Circuit Voltage - 37.1 Volts
Nominal Short Circuit Current - 8.21 Amps
Nominal Maximum Output Voltage - 29.8 Volts
Nominal Maximum Output Current - 7.71 Amps
Conversion Efficiency - 14.14%
Nominal Mass - 42 lbs / 19 kg
Dimensions - 64.4 x 39.1 x 1.6 in / 1636 x 994 x 40 mm (assembled by rivets)
Cells - 60 pcs polycrystalline
Cells Dimensions - 6.14 x 6.14 in / 156 x 156 mm
Maximum System Voltage - 1000 Volts European Standard / 600 Volts USA Standard

Warren,

I see you are getting lots of good advice concerning solar panels.
Interestingly these solar panels you have mentioned would be just about perfect for your application.
You are in the very fortunate position of starting with a clean slate and unlike many others you are not 'growing' or expanding an existing system. Compatibility with existing PVs is not a concern nor are controller limitations.

So some further thoughts...

You can NEVER have too many solar panels and too much PV power generation capability.
Try to get the maximum number of identical panels (ie same electrical specs) that  your controller and battery configuration will support and you can afford to buy.
10 of the 230 watt panels is only 2300 watts total.
The Classic 150 with 48volt battery bank will support over 4000 watts of PV input
which equates to closer to twenty of these panels.

At about 30 volts maximum power voltage (mpv) for each PV then the optimal configuration would be three of these PVs connected in series to give near 90 volts mpv.  In practice you would probably get between 75v and 90v depending on weather and insolation conditions.
This range of input is almost perfect for the Classic which is charging a 48v battery bank as it provides an optimum voltage headroom for MPPT to operate efficiently.

If you compare this to using the 72 cell type '24 volt' panels that have an mpv nearer 36volts then two of these in series gives 72v (60v to 72v) which is IMHO way too low for efficient MPPT operation and three is series is 108v which is better but gettig a bit high. You may have temp compensated open V getting too high for the 150v Classic.

So 18 of these panels configured in six strings of three looks nice with a Classic 150 into 48v battery bank.

I see you mentioned 2v battery cells. Not sure if others (or NAWS) have said anything about battery bank configuration but...
Try to configure your bank with only ONE string of series connected cells. Hopefully you choice of cell is some decent size (800Ah+ at c20) so that there will never arrive a time when you have to consider paralleling another bank.
There is NO good configuration of paralled strings, not even two.

dgd

[zoneblue]

People above have all given sound advice. I wish that i had bought two more panels at the time, i can probably get two more now but it will likely be a hassle. Just organsiing it.

Personally, theres something to be said about getting tier one panels, if you can. Tier one producers make their own cells and much greater investment in their reputation. For something that you need to last 25years, but knowing full well that no company you deal with today will still be around 25 yrs out to honor their waranties, peice of mind is all you get really.

Certainly watch our for seriously dodgy panels, of which there are some about. Your looking for a certain base level of quality. That mention of rivets pricked my ears up. Theres no rivets on modern panels. Heck, weve even seen professionally installed panels with polycarbonate faced home made panels, this one poster on NAWs, they nearly burnt his house down.

PV are so large they dont fit on a normal pallet, and shipping gets all fussy. They like full pallets/large amounts. And keeping the shipping happy is one of the keys to a sharp price deal.

[Vic]

Hi warren...,

Welcome here.

Hello Vic! Thanks for the reply!

Two things right off the bat;

AIMS has worked very hard to establish a reputation of building CRAP,  in general.

See this Thread on the wind-sun Forum:
http://forum.solar-electric.com/showthread.php?23434-New-solar-setup-and-AIMS-inverters&highlight=aims+inverter

AND,  their 48 V inverters seem to be crap,  and overpriced,  too.

Advice Taken, Information Noted, and appropriate action taken as I explained in my previous post.

You should be able to do much better with Outback,  Magnum or,  perhaps even Schneider.   All three of these companies build very good to good quality products,  and may equal to or lower in price than the AIMS.

Also Noted, and I am currently looking into Outback and Magnum brands.

Do not know about the Missouri Wind -Solar folks,  BUT,  this PV module that you list is NOT a 24 V PV.  This may seem to be a small nit to pick,  and if it is the PV that I looked at last night (a link on another Forum),  there is no name listed for the manufacturer of that PV.  As long as you are not expecting to be able to charge a 24 V or 48 V battery with "strings" one or two of these,  they may be OK.   BUT  Solar resellers SHOULD know the difference between real 24 V PVs (which have a Vmp of about 35.4 - a bit over 36 V),  and GT 30 -ish Vmp PVs (which are about 20 V nominal PVs,  FWIW).

OK. So a PV panel, that is designed for Off-Grid use, should have a 35.4-to-36volts. This is the kind of info I need to know about. The people at the store said nothing about this, and actually only stated they were 24volt panels, and it was the only 200+ watt panels they carried at their store. I had to look it up on their website to find the exact specs.

Have done business with the wind-sun company for PVs and many other items and they are honest and do a great job at filling orders quickly.  Here is their list of PVs in your range of interest:
http://www.solar-electric.com/hiposopa.html

While searching/researching, I had come across this website before, but didn't know if it was a good company or just another out a million. Thanks for the recommendation. I have begun to look through page you linked, and Now I see the difference between the specs on some of these panels compared to the ones at MW&S.

Good that you are planning to study your LOADs for the off-grid (am assuming)   system that you are planning,  and that you hope to not start small and in a few months or a year,  have to start over,  or try to use hardware that does not fit the later needs.

Start with your loads, and plan the rest of the system around them.

Yep, for sure. The power system means nothing if it can't run the loads you have.

Also,  generally small Wind turbines disappoint in the actual power they will deliver,   and fairly often it seems that there is a lot of maintenance or simply tossing out poorly designed hardware ...  I know nothing of the Missouri Wind folks or their products ...

I've heard this often now.

Just a few quick thoughts.   Good luck,   and,  the wind-sun forum is a great resource when one is designing a new system,  IMHO.    Vic

Thanks for your Reply and Info!

[Vic]

OK. So a PV panel, that is designed for Off-Grid use, should have a 35.4-to-36volts. This is the kind of info I need to know about. The people at the store said nothing about this, and actually only stated they were 24volt panels, and it was the only 200+ watt panels they carried at their store. I had to look it up on their website to find the exact specs.

Thanks for your Reply and Info!

Hi again warren..,

Thanks for the detailed replies and the added info on your goals for your system.

Just to try to be a bit more clear on what I was trying to say about the Missouri folks's "24 V PV module" ...

I was NOT trying to say that you needed a real 24 V PV.  The decision on exactly what your string voltage (and therefore the desired Vmp of the PVs you use) that your system needs to satisfy the Charge Controller (CC) and the battery will happen much later in the design process of your system.

It is quite possible that you can/will use the 60 cell PVs,  with their nominal 30-ish volt Vmp,  as they are much more common,  and often relatively less expensive than the actual 24 V PVs.

I WAS simply trying to say,    "   ...  beware of resellers who seem to be sloppy with their descriptions of products that they sell,   are trying to possibly mislead customers,  or have made an error that has not yet been corrected ..."   but beware,  in any case.

It looks like you are being studious,  and are starting your design by asking questions,  and evaluating the answers.

It is terrific that you cancelled the order for the AIMS inverter.  That is a great move,  IMO.   Good Luck,  and let us know how you are progressing.  Thanks,   Vic

[RossW]

The previous owner had this well drilled and pump installed last fall. So everything is basically brand new.
I have contacted the well company who installed it, and found out that the well was 450 feet deep (normal for this part of missouri) . The well Pump was positioned at 400 feet, and the static water level was 320 feet. Because the well is so deep, there is Very Limited options on how to be able to pump this water up, with out grid power. This is one of the reasons why I would just rather figure out a power system which can run the pump that is already installed.

They also told me that the Well Pump is a 220 volt 1.5 HP. He also told me that it would take at least an 8000 watt generator to safely run the pump with-out risking burning up the motor over time.

That sounds like utter piffle to me - either the guy doesn't know what he's doing, or is trying to scare you into something far beyond what you need.

I live in Australia, on 22 acres on the side of a hill. I don't have QUITE the same situation as you, but in many regards it's similar. At the bottom corner of my place I have a 30,000 gallon concrete water tank which will (only just) gravity feed from my local town water supply. I have a submersible deep-well bore pump designed to go down a 4" bore installed in that bottom tank, which runs into 1 1/2" heavy poly pipe, and feeds another 30,000 gallon concrete tank up by my house.

This pump has to push water 200' vertically and 800' horizontally - the total head is probably not very different to your well pump.

My pump takes a nominal 800 watts (a little less than yours). I only have a 5KW inverter, and it has to run everything else in the place at the same time. The inverter starts and runs the pump perfectly happily. If you have a decent inverter, there's NO WAY you will need an 8KW generator (or inverter) to run a decent well pump!

[laszlo]

I want to chime in with RossW, the pump that you already have is not going to require 8KW inverter.

1 HP is roughly 750 watts, and usually electrical motors will draw 1000-1200 watts to perform 1 HP of work, and voltage is not relevant. ( 1 HP is 1 HP.whether it is 120 or 240 V) So if you have a 1.5 HP pump you should be able to run it off 15amp breaker (hoping previous owner installed a breaker). So a Magnum PAE 4448 for example will be able to run this load.  This inverter has high surge (8KW), and you will find similar performance  in this class  of inverters from other manufacturers.  Your system should have the largest possible wire size (4/0) from the battery to the inverter, so you can take advantage of their inherent surge capability.

As far as well-pumping, I am on a 480 foot deep well. I use a pumping method  called "air lift" system. There is no pump in the well bore, but compressed air is pumped into the the bore at 360ft depth  via 1/2 copper pipe sheaed in PVC. I use  Thomas Industries oil-less compressors. Works really well, and it's self cleaning system so you have no algae and such. I am not suggesting you change your exisiting system, but wanted to provide another idea of what alternative pumping solutions are out there.