New from Eastern Wa

kamchuka

Been poking around for a place to look at some off grid energy set ups. Looks like I found it!

Small system looking to upgrade. 4 panels of unknown origin (previous owner installed and I plan on updating), 6 trojan L16 6v, magnum 2500, 10k diesel Gen. 20 acre place was purchased a year ago I retire soon and me and my lady are geeeet'n out.

Photowhit

We will need more information; What type of loads will you have? Will you be full time off grid? What are your goals (you could use the existing system and run the generator when needed.) Would you like a system that only required the genny a couple times a year or a couple times a week? 
...of course it all comes back to loads, what will your needs be?

System; What system voltage, with there being 6 batteries, I'll bet you have a 12 volt system now. If you wanted/needed to go larger most of your existing system will not be usable. 2500 watts is larger than most of us, here would recommend for a 12 volt system.

You battery bank could only be configured for 24 volt use by dropping 2 of your batteries and then it would likely be undersized. Batteries age together, so adding to the existing battery bank is not really an option.

You charge controller (between the panels and the batteries) will likely be okay for 24 volt system but may not, and likely won't work with a 48 volt system. The inverter is for a 12 volt system. The panels would likely be fine as supplementing a new array.

Once more your loads are paramount. If you can get by with the same of less loads than the original design, you could/should stick with the original design. At least until the batteries expire. You could add panels to lessen the run time of the generator, but decide on the future system and plan and buy panels with the future system in mind. Be wary of panels and charge controller Output and limits. Many panels are sold today that will be described as 24 volt panels, but are designed for a grid tied system. Also some larger panels must be purchased in 3's to fit within the panels and charge controllers limits.

BB.

Welcome to the forum. Congratulations on reaching (just around the corner) retirement!

I like to ask people what they plan on their power usage? Without that, it is very difficult to design a cost effective/reliable off grid power system that will meet your needs. Also, roughly, where will the system be installed (nearest major city with similar weather).  So--some suggestions.

In general, off grid power is expensive--~$1-$2+ per kWH (around 5-10x the cost of utility power) is common when you roll instillation+maintenance+new batteries and new hardware over the 20+ year life of the system. A few folks have gotten their costs down towards $0.50 per kWH--But it take great dedication to do that.

So--Conservation is your first priority... It is almost always cheaper to conserve than it is to generate power. LED lighting, energy star refrigerator, "solar friendly" well pump, laptop computer vs desktop, etc.

To give you an idea of how much power you may need:

• 500 WH per day (0.5 kWH per day or 15 kWH per month)--LED lighting, DC RV pump, radio, laptop
• 1,000 WH per day (30 kWH per month)--Nice off grid cabin above, perhaps add summer fan, more LED TV+Laptop use
• 3.3 kWH per day (100 kWH per month)--Add energy star refrigerator, deep well pump, washing machine, a few kids/guests, near-normal "electrical life" for off grid home (still lots of conservation)
• 10 kWH per day (300 kWH per month)--Add mini-split AC/Heat pump for some solar cooling/heating, some electric cooking.
• 500 kWH-1,000 kWH per month--Typical North American home power usage
• 1,000-3,000 kWH per month--Typical home with AC in Texas/Florida with electric heat/electric hot water/etc.

The first three (500 to 3,300 WH per day) is a very doable off grid system... Larger than that, you are talking A LOT of money and probably needing a professionally designed/installed off grid power system (find the right company) and getting close $50-$100,000. the smaller systems can be done for (maybe) $20,000 or less (3,300 WH per day system).

The 10 kWatt diesel genset, if it is in good shape, is probably worth keeping around to run shop loads, emergency backup--But you will probably need/want a smaller genset too for bad weather/battery charging/etc. Large gensets with small loads are not very fuel efficient. Diesels, when run at less than 40-60% load can have issues too (wet stacking, cylinder wall glazing, carbon build up)--New diesels may have less of an issue with wet stacking and such--And diesels are more fuel efficient vs gasoline (especially at lighter loads).

Roughly, a 3.3 kWH per day will cost roughly 3x more to build and operate than a 1.0 kWH per per day system. So, it is very important to get an idea of what will be "nominal energy usage" for you. Energy usage is a highly personal set of choices.

You can get a Kill-a-Watt type power meter and measure the usage of your present smaller loads (i.e., plug in loads). You could even wait until you get into the new home and run from a genset (your diesel and/or a smaller genset like a Honda eu2000i which will run most of your daily needs on 1-2 gallons of gas per day).

And, look at the cost of bringing in utility power... If it is less than ~$20,000--It may be cheaper than an off grid solar power system. And, as you can see, off grid solar does not add much value to the property. Having utility power can add value to the property/make it easier to sell down the road (and the costs to bring in power seems to be going up--not getting cheaper).

-Bill

kamchuka

I've estimated or daily needs as around 5kw. However I will add a normal size fridge and box freezer in the future. We will be full time of grid.
I'm very new to this. I'm savvy and have been collecting parts and pieces for years but the solar side I'm just dippin my toes in.
Here's the basic lay out of the house. Rv fridge, dryer, water heater, stove all on propane. We don't really need allot of energy but we prefer a little more tv time than the gent who owned it prior. I also will be working in the shop more thus requiring more power. My goal would be less generator, maybe once a week or two in the prime months, little more in the winter.
Your reply startled me, I want expecting such a detailed response haha. Thanks very much! I'll have more answers and questions as the next few months roll on. We plan on moving in next summer. I'll run the current system till the following summer after I build a power building and consolidate all the various pieces. It's all over the property right now. Panels 150' from batteries, geny in a lean-to down the hill, inverter in the bathroom....etc.
Thanks again

BB.

My first suggestion is not to pre-buy any solar hardware until you have worked out a paper plan/design. Depending on the size of the system, you will probably need different components. And batteries do not sit on the shelf well--They start to age as soon as they are built--And need occasional recharging while in storage.

And that is 5kWH ("hours") per day?

If you have/get a late model LED TV, they use a lot less energy.

-Bill

kamchuka

Yes sir 5kwh. Nomenclatures, lingo, and acronyms are all new to me but I've got my head wrapped around most of it (math be damned). We spent three weeks there after closing in July and I'm certain we used less but that's my high estimate. I plane on living a year or so on current system for evaluation purposes. I am building a system for the shop though. Get my feet wet and mess ups are ok lol.

Photowhit

kamchuka said:

I plan on living a year or so on current system for evaluation purposes. I am building a system for the shop though. Get my feet wet and mess ups are ok lol.

This makes a lot of sense, as Bill said, I wouldn't buy anything until you have a better idea of what your needs are! Expensive mistakes are made now! 5 kwhs a day would put you near the 48 volt system range. Perhaps a 24 volt with the generator use.

Washington has a lot of micro climates, what are you near? This will help determine the amount of sun you'll see (Solar insolation)

BB.

Roughly, where is the place--Need to figure out how much sun you get (not on the coast, with lots of marine later anyway).

If that is a Trojan 6 volt @ 420 AH battery---6x of those--2 series x 3 parallel -> 12 volt @ 1,260 AH battery bank.

That requires quite a bit of solar power to keep "happy". Nominally, 5% to 13% rate of charge from solar. 5% minimum (weekend/seasonal cabin). 10%+ recommended for full time off grid home.

With 4x unknown panels--Either they were using the genset a lot, and/or the batteries are not in very good shape from under charging/over discharging/deficit charging and you should not count on them.

Nominally, over an ~800 AH battery bank, should jump up to the next voltage battery bank (1,260 AH @ 12 volts -> 630 AH @ 24 volts -> 315 AH @ 48 volt bank are all the same size). Obviously, your 6x battery bank cannot be configured into a 24 or 48 volt battery bank... So, that is for your next design (if you have 1-2 bad batteries, you can configure into a smaller 4 series battery bank and a new inverter+charger+etc. -- obviously, any changes risk costly a lot of money..

For your present system, our rules of thumbs for off grid systems (reliable, workable):

• 1,260 AH * 14.5 volts charging * 1/0.77 panel+controller derating * 0.05 rate of charge = 1,186 Watt array minimum
• 1,260 AH * 14.5 volts charging * 1/0.77 panel+controller derating * 0.10 rate of charge = 2,373 Watt array nominal
• 1,260 AH * 14.5 volts charging * 1/0.77 panel+controller derating * 0.13 rate of charge = 3,085 Watt array "cost effective" maximum
  

Your 2,500 Watt Magnum inverter is sized fine for you present battery bank--But it may be a MSW inverter--That is not great for running induction motors and some electronics. Very roughly, 80% of your stuff will run OK on MSW; 10% may or not; and 10% will have a shortened life/run hot.

Modified square wave inverters can also cause lights/appliances to buzz at 120 Hz. Longer term, I would highly suggest looking at (more expensive, unfortunately) a TSW/PSW (true or pure sine wave) AC inverter. Much better choice for full time off grid (runs all AC appliances/devices just like utility power).

Just to give you an idea of how much power a "nominal" array could give you:
http://www.solarelectricityhandbook.com/solar-irradiance.html

Walla Walla
Average Solar Insolation figures

Measured in kWh/m2/day onto a solar panel set at a 44° angle from vertical:
(For best year-round performance)

Jan	Feb	Mar	Apr	May	Jun
2.16	3.32	4.59	5.43	5.65	6.00
Jul	Aug	Sep	Oct	Nov	Dec
6.33	6.20	5.46	4.03	2.50	1.81

Toss the bottom three months (need genset), gives us February as the break even month:

• 2,373 Watt array * 0.52 typical off grid system eff * 3.32 hours of sun per day =;4,097 WH per day (Feb long term average)

And if you use 2 days storage and 50% discharge from your battery bank (typical optimum usage):

• 1,260 AH * 12 volts * 0.85 inverter eff * 1/2 days * 0.50 max discharge (for longer battery life) = 3,213 WH per day (from battery bank)
  

If you have some critical/smaller loads (TV, laptop, cell phone charger)--You might want to wire up a second MorningStar 300 Watt TSW 12 volt AC inverter (includes remote on/off and "search mode" for low power standby).

The system size is not far from your 5 kWH per day power needs--But, you will probably need to rip it all out and start over (mix of non-optimum configuration/equipment)--Don't know, just guessing.

Perhaps just some more solar panels, another charge controller (for new panels), and a Morning Star inverter--And you can keep it running for a few years (until the batteries die on you). Then you will know your needs better.

Anyway--Some quick math and thoughts (and you thought there would be no math here ).

-Bill

kamchuka

Bill! My lady is listening to me read this outloud....she said "you understand all that?" Of course I responded with "uh huh".....I'll research all that and get back to you. May be a while lol. That may be the best, most articulate response I've ever received..
Thank you!

kamchuka

Oh....I'm 2 hours from spokane almost to Canada. 6 miles up a goat trail so no chance for city power.

BB.

It is always a bit of a debate on when I need to explain more vs less... It is difficult to do typing on a forum and missing the body language and voice cues when talking face to face.

Remember, I am using a lots of rules of thumbs that r based on experiences from many others on the and basic electrical formulas, most of which are the simple variants of:

We use these rules of thumbs to get a system that is "close" to what will work for you, without 3 more pages of calculations and data.

It is a starting point (and usually pretty close to optimum) for system design and give you the basics for a paper design and costing of your system.

By the way, here is the data for a 45 degree tilt for Spokane (different program):
http://pvwatts.nrel.gov/pvwatts.php

Month	Solar Radiation ( kWh / m2 / day )
January	2.32
February	2.96
March	4.26
April	5.12
May	5.57
June	5.66
July	6.98
August	6.65
September	5.62
October	4.48
November	2.23
December	1.92
Annual	4.48

A bit less sun farther north... Feb = 2.96 hours of average sun (noon time equivalent).

You also spoke of the array being 150 feet from the batteries--You need full sun on the panels 12 months of the year--If you have even partial shading on one or a few panels, you can lose 50% or more of the array output while the shade is present. Between now and late December (shortest day of the year)--You might want to watch the track of the sun and how shadows play across the property--and perhaps mark a few trees for conversion to lumber/firewood. (there are tools you can get for estimating shading losses--But this is easier). You want sun on the panels for 9am-3pm at least (more sun is always better).

Note--The "numbers" are no where near that accurate--Within 10% of any of the above power/wattage/AH numbers is pretty much "dead on" for solar. I included the digits so you can reproduce my math (not my mistakes) and see how I use the results from one formula down in the next set of calculators (better than labeling everything variable A/B/C and plugging into a spread sheet). It also helps reduce round off error as we go through three or more sets of calculations.

You will find websites and spread sheets that give you similar information as you supply the input numbers. However, they kind of "hid" many of the assumptions/decision points, and it makes it (in my humble opinion) more difficult to get a "feel" about how one change affects another item in your design.

I also write the equations to sort of read like an English sentence (I was a C student in grade school English and math, why do you ask?) so you can understand better how the elements relate to your overall design.

Anyway, please feel free to ask questions--We all started at the same point, and folks here are always willing to help.

Happy Retirement!
-Bill

mike95490

Welcome to the "club"  Off grid is a MAJOR change.  I think the break even point of using electric over propane is just a couple years, so you may want to consider buying panels vs propane and hauling tanks around

Dave Angelini

Spend as much time as you can there this winter before your summer move.
It is the best time to look for array locations. I would plan an eastern and western location or use tracking.
With the high voltage solar charge controllers you can be 1,000's of feet from the batteries and I would avoid remote loactions for the equipment and batteries. keep them close to where you can see them easily each day. Feel free to drop an e-mail.

kamchuka

I've done a little research and I think I'm going in this direction.

Magnum 2500 (current inverter) 12v

4 more Trojans giving me 10 wired series parallel for 2100 ah

6 Canadian solar 315p's 1890w total (25 year warranty)

I think this would meet all my needs as this will only run the house. I would prefer to go 24v or 48v but its too much doe and I don't think I need it. I would rather change my habits than throw more money at it....that's the whole point for me! I'll be on an Army retirement budget, but I want the creature comforts as well, some anyways.

I have plenty of time to work out the details though. I'm building a power house, but not for two summers from now. Chances of me updating the system this coming summer are slim but possible, so I want to be ready to pull the trigger if so.

What's your thoughts on this system? compatibility etc.

kamchuka

Bill, I have asked a few people about these batteries, SAFT 1.2v flooded nickel cadmiums. any experience with them? I came across a bunch of them set for recycle and they where new so I snagged em. I'm not sure what to do with them. I kind of had to take em or leave em so I figured I could use them somewhere.

Photowhit

kamchuka said:
Magnum 2500 (current inverter) 12v

4 more Trojans giving me 10 wired series parallel for 2100 ah

6 Canadian solar 315p's 1890w total (25 year warranty)

...I would prefer to go 24v or 48v but its too much doe and I don't think I need it. I would rather change my habits than throw more money at it....

What's your thoughts on this system? compatibility etc.

Be aware, New batteries don't play well with old batteries, NOT recommended! I have suggested using what you have and when they die buy new, even if you aren't going to switch to a 24 or 48 volt system.

More than 2 strings of batteries can create problems, 3 is okay but iffy, I personally would NOT do 5 strings ever!

6 - Canadian Solar 315's is a Good quantity! They have a VMP of 36.6v so strings of 2 would work for 24 volt or strings of 3 for a 48 volt system.

In a 12 volt system and a long distance you will need 2 charge controllers to add 6 panels to a 12 volt system, such as the Midnite Classic or Outback 80! at @$600 a pop! Please note that if you went to a 24 volt system you would only need 1! That would be $600 toward a new inverter! Charge controllers work on the basis of amperage through the unit, at 12 volts 1600watts of panels could produce as much as 130 amps, at 24 volts 65amps...

Also the Magnum 2500 inverter you have is a modified sine wave inverter. It can create issues with some electronics as well as shortening the life of motors such as refrigerator compressors, fans and tools. Also motors will use more energy with a MSW inverter!

kamchuka

Dave Angelini said:

Spend as much time as you can there this winter before your summer move.
It is the best time to look for array locations. I would plan an eastern and western location or use tracking.
With the high voltage solar charge controllers you can be 1,000's of feet from the batteries and I would avoid remote loactions for the equipment and batteries. keep them close to where you can see them easily each day. Feel free to drop an e-mail.

Thanks Dave, I still have 6-8 months here at FT. Lewis and moving in the winter is not an option, even getting there is a task as the roads are not maintained. I understand my winter needs will be vastly different, so I'll most likely spend a decent amount in fuel the first winter. Fortunately the previous owner left a couple hundred gallons of diesel for us! I sea foamed and sealed it all up a few weeks ago. 15 cords of seasoned split fire wood as well!! pretty stoked about that. I painted the ends with green "locates" paint, wood is the commodity of the hills...My closest neighbor was BUMMED!

westbranch

Don't sell them, keep them they should be much healtier than the 30++ year old 100Ah rated ones I have....and they are tough..... 10 = 12 v , 20 = 24V, so if you have 40 you can have 2 PARALLEL strings of  'X'Ah @ 24V and get started on a higher voltage setup for the house.... appear to be 34 Ah for 1 hour discharge, which would be a bit higher at 20 yr rate...  trying to find data on SAFT site is a pain, you need to tell us what they were used for or what industry the were used in...

kamchuka

westbranch said:

Don't sell them, keep them they should be much healtier than the 30++ year old 100Ah rated ones I have....and they are tough..... 10 = 12 v , 20 = 24V, so if you have 40 you can have 2 PARALLEL strings of  'X'Ah @ 24V and get started on a higher voltage setup for the house.... appear to be 34 Ah for 1 hour discharge, which would be a bit higher at 20 yr rate...  trying to find data on SAFT site is a pain, you need to tell us what they were used for or what industry the were used in...

They are used in the aviation industry. They where ordered wrong, so they where going to have to dispose of them costing some pretty serious doe, dude just gave em to me...NIB. I drove home with 95 of them = 5X24v banks thinking "holy grail, holy grail" then after asking around and doing some research, some think they aren't good for off grid solar. As a noob I'm thinking storage is storage, but.... I get all things are not as they seem. Still I should be able to find a use for them. that's a lot of AH's

Thom

Your needs are to big for 12v . 

thom

westbranch

kamchuka said:

THey are used in the aviation industry. They where ordered wrong, so they where going to have to dispose of them costing some pretty serious doe, dude just gave em to me...NIB. I drove home with 95 of them = 5X24v banks thinking "holy grail, holy grail" then after asking around and doing some research, some think they aren't good for off grid solar. As a noob I'm thinking storage is storage, but.... I get all things are not as they seem. Still I should be able to find a use for them. that's a lot of AH's


Ask your friend  what they reordered....It looks like  a secial order   SPE ..cial?  since it does not show up in a search of SAFT site

Thom

It's go big or Pay twice . Just go 48v and save your self the headache 

thom

kamchuka

I don't really know the guy, but I do know they sat in the warehouse a long time. He seemed excited to get rid of em. I kind of doubt he knows what replaced them due to high rate of turnover in these G# positions. I'm sure they are made specifically for something in our inventory, but they exist in the civilian world as well in a different package.

kamchuka

Thom, I'm trying to keep it sized at my needs. I don't really need more power just storage, I'm understanding they go hand in hand now. I don't want to be this guy

westbranch

Hard to tell if they have fluid in them or not....?

kamchuka

They have fluid, ready to rock.

kamchuka

I think this weekend I'll wire up a 12v bank and do a side by side test with one of my trusty interstate rv batteries. Seems like people don't like the interstates but mine have been flawless in many applications. Plus they are tuff. I leave one with an 800w inv on the front of my quad for mobile ops. Saws, cordless charger, radio, etc. They just keep going.

Photowhit

BTW - Even off grid systems qualify for the 30% tax credit for solar residences, applicable the year they are installed. This is cut back in a couple years and may end a couple after that. This is a direct credit off any tax liability, spend $100 get $30 off your tax liability. This also applies to 2nd homes (so long as you don't rent them)

kamchuka

Photo, they still doing that in Wa state? I heard they shut it down or its coming soon.

Photowhit

WA State has nothing to do with it, it's a federal program.

http://energy.gov/savings/residential-renewable-energy-tax-credit

You might check on the 2nd home, which might apply to you if it won't be your primary residence for half the year. They could have changed it when they extended the credits.

kamchuka

Nice! Thanks for the link!