Advice on off grid solar setup

[Jedon]

I'm building a house on 97 acres in the woods of Northern California and it's not near any power so I'll need a nice solar setup. My wife is concerned that I'm going to go off to work and leave her with no power hehe.

Some people are saying I don't have the budget for enough panels so I should have a large battery bank and use the generator to keep them topped off. Other people say I can get by with a smaller overall system.

It's a 1900SF house with CFL's and made from SIPs but we do have 3 computers and a 62" DLP HDTV, we don't want to give up all modern luxuries. We'll get brand new appliances that are as energy efficient as possible.

I have a small generator from Costco: Cummins Onan 5KW 13HP gas generator

Here is my guess of a decent setup, kind of in the middle of the various pieces of advice I've gotten:

PV Panels - 16 Kyocera KC-200GT    $13,600.00

(2) Crown 12-125-13 Industrial Fork Lift Battery 24 volt, 935 AH    $6,550.00

Inverter -2  Outback 3600W    $3,508.00

UniRack Mounting    $500.00

Misc other Solar Equipment    $2,000.00

Outback charge controller MX-60 w/remote display    $498.00

I'm currently doing a energy audit with the Kill A Watt but haven't finished yet.

Thank you for any and all advice!

-Jedon

[DanB]

It seems reasonable what you've come up with.

You probably have - but you might look at finished power panels too, they're very tidy and make inspectors happy!  I get a fair amount of stuff from 'the alternative energy store'.

You might also look at their 'package deals' - I think you can save a good bit and it spares you lots of trouble shopping.

http://store.altenergystore.com/Kits-and-Package-Deals/c447/

[Jedon]

Thanks I'm reading about those package deals right now. They use Xantrex inverters, I heard that since Xantrex got bought out they haven't improved their products and Outback has so it's better to go with Outback, anybody have opinions on that?

By "Finished Power Panels" you mean like the Outback enclosures?

I have plenty of room so am planning on having the panels be about a 100' from the house mounted on racks not very far off the ground and have a little shed to keep the inverters and batteries in and a separate shed for the generator ( cinder blocks to keep noise pollution down and help with the fire hazard ).

[SteveCH]

Locating the array 100' from the house, which I assume means 100' from the batteries and controls, etc., will necessitate wiring the panels into maybe at least 48 v. groupings. Well, not necessitate, but require some pretty large wiring diameters. Not a problem if you have the bucks to spend several bucks a foot, but maybe you are planning a higher voltage grouping anyway. I just mention it to make sure you realize this. There are charts available to calculate the percentage loss given the voltage, distance, wire gauge, so you can decide. [For example, I found, in my case, it was a matter of somewhat larger wire and somewhat larger panel array together to make the best financial sense]. The higher the voltage from the array [panels], the smaller diameter wire you need for the run to the house. And make sure your controller(s) will handle the input voltage you will be running from the array.

I have some Outback controllers, great stuff. I also use a Trace inverter and have for the past 15 or 20 yr. Trace is now Xantrex, so I assume the same quality. The Trace has been on for all that time, maybe shut off for a couple hours total. So, its reliability is supurb. Now, 20 yr. of technological advance means something, and no doubt the new Outback inverters are also great stuff. You can compare the costs, features, efficiencies, etc., on your own [and I will if and when the old Trace ever gives up], as I don't know them. Someone else here on the forum likely does. But I have been very, very happy with my Trace/Xantex, and I've very happy with my Outback controllers [MX-60s].

[Jedon]

I want to put all the inverters and batteries in a shed right next to the panels so I can run cheaper wire the 100' to the house.

I guess the newer inverters might be more efficient? I'll do like you suggest and research the features to see if the undoubted increased cost is worth it.

[Off grid in Tonopah]

Hey Jedon

    I've been off grid for 5 years now and from what you listed it looks as though you have a good setup planed. I would suggest that you go with propane on as many appliances as possible and you should have more than enough capacity. I promised my wife that she wouldn't notice a difference in life style being off grid and so far it been no problem. We have all the bells and whistles, Sat TV, internet and computers we don't worry about phantom loads and living off plug strips and such. My system is only 1100w of PV and a Lakota wind turbine. I have to run my generator every other day for an hour or two in the winter to pump my well and do loads like the washer and I top off the batteries. With your system you should be able to go longer though. I also have my battery house and inverter away from the house proper and use the long run of wire at 110/220V like you plan on doing and I like the idea of not having all that gear in my house. The only suggestion I would give you is to get a good diesel generator. You can get bulk off road diesel delivered and the generator will last forever if you change the oil and air filter often. I tried the 3600 rpm gas thing and the noise is bad, dealing with the fuel sucks and they burn up if used for any purpose other than standby, just my two cents.  Short of that good luck and let me know if I can give ya any help in the planning dept.

                                 Bob

[dudevato]

Jedon,  I saw the part about you being in northern california.  My brother lives in Red Bluff, 30 miles south of Redding, right on Interstate 5.  Anyway the last few times I was up there I noticed a solar panel store just south of town, maybe 5 or 10 miles, about a 1/4 mile off the interstate on the east side. It had a sign and some panels showing. I was thinking maybe if they gave you a good price you'd be able to save on shipping.  Anyway, good luck.  dudevato in southern california (Lancaster - 60 miles north of Los Angeles)

[Jedon]

I have heard that a diesel generator is by far the best way to go, I just got the little one as a first step. I'll wait and see how much it costs me to build the house before I decide on a "final" generator. Thank you for the advice though! Good to know I can still have all my electronic goodies and please the wife as well and be off grid.

[Jedon]

Thanks, there are actually a lot of solar places up here including some companies like Sierra Solar that do a lot of volume. Once I spec a system I'll bid it out and see who has the best price.

[DanG]

http://www.hupsolarone.com/specs.htm

I think if I was doing off-the-shelf system I believe I'd be using these batteries, looked at them for years and have yet to find whats not to like about them, that is besides prices rocketing higher but it's the same everywhere. For used batteries the motive-power banks are a winner though..

The free delivery helps too.

[Nando]

Jedon:

How far is the GRID installed and how far is your next "door" neighbor ?.

Go for 48 volts Battery bank, though for me a higher voltage would be better.

Get a Diesel form the beginning.

If you land has a stream with some head, it may be one of your best assets

>CFL's and made from SIPs --- Please translate the meaning !!

How is your land, wind regime, for a wind mill ?.

Get the inverters that can work together and at the same time get a transformer to transfer power from one line loads to the other line loads in case of a failure of one.

Since your wife may be alone when you are working then do a set up where she could easily disconnect the equipment but allows her to run the Diesel until you return and teach her step-by-step how to do maintenance if you are not around.

You have more than sufficient solar panel, though check your area to determine how many days a year the Sun goes "sleepy" and "stays in bed ".

How is the winter solar power around there, it may require constant engine operation for several weeks.

Nando

[Volvo farmer]

Wow! you'd have over four times the solar I've been running for the last year! <power jealousy>

My only caveat would be that that generator seems a little small. I've got an Onan LP powered unit rated at 4KW or so and it doesn't play well with the charger built into the Outback inverter. If I really try and juice the batteries at close to full output, I end up with about 135VAC into the house, which tends to let the smoke out of things like 62" DLP HDTVs, washing machines, fans, etc.  Maybe my voltage regulator on the genny is fried but when I went into researching this problem last winter, I heard a lot of solar installers recommend a 10KW generator for my battery bank, which is similarly sized to yours.

Since you already bought it, I'd say use it, but be aware that the battery charger in Outback inverters seems to put an unusually high inductive load on a small generator, resulting in crappy waveforms and possibly high voltage peaks.

Some of the brains of Outback have since moved to Magnum, and you might want to give them a shout before buying your inverters. In my latest issue of Homepower, I saw an ad for a single Magnum inverter that did 120/240V. And their chargers are advertised as "power factor corrected" which might have alleviated some of the problems I had charging batteries with this small generator. YMMV.

[wdyasq]

'I tried the 3600 rpm gas thing and the noise is bad, dealing with the fuel sucks and they burn up if used for any purpose other than standby, just my two cents.'

Well said Bob ...but you forgot clean fuel.

And on that note I must admit I haven't changed the oil in  my truck for the last 60,000 miles. I am 'testing' a 'by-pass filter system'. As I normally get 250k - 300k miles from a vehicle before electrical or just persistent small repairs cause me to retire them, this test is still in the infancy stage.

I do believe a good by-pass system will increase the life on any internal combustion engine. As resources allow, I am gradually putting together parts for an off-grid electrical system. I do plan on a converted 6 pole motor hooked to a small diesel for a generator so I can run the diesel at 1200rpm. It will have 'super filtering' on the oil and fuel systems as well as oversize air filtering. I will probably setup the diesel to run on heavier oils also.

I think one of the most important, and forgotten details is building the super efficient house in the beginning. The orientation should be designed to take advantage of the climate, not the scenery. This is at times difficult in 'domestic' situations.

Good luck to all those attempting off-grid. Congratulations to all those who have attained it. (although some with think it is selfish and self-centered to not be grid connected).

Ron

[Jedon]

"How far is the GRID installed and how far is your next "door" neighbor ?."

GRID is at least $500K away... 10 miles maybe?

I'm not really sure where the nearest neighbor is who lives there, there is a guy with a cabin running off a generator a few miles away, I saw him once...

"Go for 48 volts Battery bank, though for me a higher voltage would be better."

I am now planning to use 40 6V 220AH golf cart batteries from Costco.

"Get a Diesel form the beginning."

Well... I will as soon as I can afford it, I'd like to spend around $5K and get a real nice one but it will have to wait a year.

"If you land has a stream with some head, it may be one of your best assets"

Yes I fully plan on putting a pelton wheel on the 30gpm/100ft head spring as a project once I'm out there.

"How is your land, wind regime, for a wind mill ?."

I think there are a couple places not too far from the house where a windmill would work, I plan on tackling that after the hydro.

I have cut down the initial number of panels to 8 Kyocera 205W panels for a total of 1640W, I have done some energy saving tests at my current house and am confident that we can cut usage down to 400KW/h per month or 13KWh/day.