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Solar Power

ArroyoTaxi - 6-29-2009 at 08:38 PM

Hey Nomads - any of you have solar panels? if so, what kind, how much and what are your experiences with it? Thanks in advance for any info. cheers.

Bob and Susan - 6-30-2009 at 05:38 AM

first you NEED to deceide what voltage you are going to use

12 or 24 or 48

then buy the correct voltage solar panel so there is no need to wire smaller vooltages together

thats first :light:

Russ - 6-30-2009 at 06:03 AM

Bob and Susan have the most sophisticated system I've seen on this forum. Try a search here and you'll see what is popular and what works the best. You'll want to decide what your needs will be and then ask questions as you build your own solar system.

larryC - 6-30-2009 at 07:27 AM

Arroyo
The best prices I have found on panels lately are here: http://sunelec.com/
As far as the voltage is concened, you do not necessarily have to buy panels to match your systems voltage if you get an MPPT controller. A good mppt controller will down convert your panel voltage to match your system voltage whether it is 12, 24 or 48 volt. If you are just going to put together a small system for a few lights then an mppt controller probably would not be worth the expense. If you are putting together a system to run a house with an elec refer then it would be worth the expense.
Anyway you asked about panels, I bought 6 of the 190 watt panels with cosmetic blemishes from Sun Elec and am very happy with them. I see now that they have 200+ watt panels now for less than $2.50 a watt. Thats a better deal than I got 2 years ago.
Hope this helps,
Larry

Doug/Vamonos - 7-3-2009 at 08:36 PM

I inherited a 12-volt system when I bought my place. It has three panels - two 80 watt and one 100 watt, or thereabouts. The panels feed four Trojan 105 6-volt batteries that are wired in series for 12-volts. This is a very simple system that works fine for my needs. I am rarely there for more than three or four days and the batteries power up my fans, lights, stereo, and water pump in the trailer. I also use a generator for the coffee pot and microwave. Fridge, water heater, and furnace run on propane. Like I said, this is a minimal system for a trailer.

A good experience here

beercan - 7-3-2009 at 09:00 PM

I have a 100% solar house. I have 8--160 watt panels feeding an Outback inverter/ MX-60 controller and 8- L-16 batteries set up for 48 volts. My home has 2 bedrooms and 2 baths with garage. I have a new 20 cubic ft refrigerator, and 2 -7 cubic foot freezers along with satellite Television --35 ", Hughes Satellite internet and other misc. electrical appliances including a well pump.

I installed this myself 4 years ago and have had no serious problems since that time.

BCSTech - 7-4-2009 at 06:01 AM

Quote:

Originally posted by soulpatchI also have 8 US215 batteries which are not nearly as nice as the L16's

You should probably stick with the smaller batteries. 520 watts in panels is not enought to support a stack of eight L16s without a lot of help from your gennie.

astrobaja - 7-4-2009 at 07:33 AM

Hi ArroyoTaxi,

Our panels are 9 X's 195 Evergreens feeding a Outback MX80 and 2 Outback inverters (although I have yet to use the slaved secondary one),
and 12 X's 395 Ah 6 volt Crown batteries.
The rosarito company that installed our system was way too pricey, the panels are available through Arizona Wind & Sun for $825 if you buy 10.
Our system runs all the lights, 25 squre foot fridge/freezer, modem/computer, tv, guest house, and a kickass home theatre with a big subwoofer and 7 channel 260 watt amp.
We do need a bit more battery storage if I am to use the home theatre at night without having to run the gen, so far we have not needed to run the gen in the 5 months with the system.

Heres Arizona Wind & Sun website:
http://store.solar-electric.com/hiposopa.html

k-rico - 7-4-2009 at 07:55 AM

Quote:

Originally posted by beercan
I have a 100% solar house. I have 8--160 watt panels feeding an Outback inverter/ MX-60 controller and 8- L-16 batteries set up for 48 volts. My home has 2 bedrooms and 2 baths with garage. I have a new 20 cubic ft refrigerator, and 2 -7 cubic foot freezers along with satellite Television --35 ", Hughes Satellite internet and other misc. electrical appliances including a well pump.

I installed this myself 4 years ago and have had no serious problems since that time.

How much does a system like this cost, +/- ?

BajaRob - 7-4-2009 at 10:15 AM

Our solar array consists of 20 Kyocera panels, KC-120s, KC130s, and KD135s. They are divided into two combiner boxes which feed two C-60 charge controllers via fused disconnects. The panels are 12 volt and it was a very easy matter to wire them in series when I upgaded to a Xantrex SW4024 inverter. After seeing 3 of our neighbor's Trojan L-16s fail after 3 years I decided to stay with smaller batteries. After 5 years of service my Trojan 105s were still going strong. I sold them for about 60% of what I had paid and replaced them with 20 Energizer 220 amp golf cart batteries from Sam's Club in Yuma. The cost including core charge and tax was $70. On a good day we bring in about 12KW and have enough to power an 18, 22, and 4 cu/ft refers, 2- 32" tvs, 3- computers, etc. For those cloudy days we have a Yamaha 6500 diesel and Honda 7000i gas gensets. Solar panel prices have been dropping of late.

[Edited on 7-4-2009 by BajaRob]

BCSTech - 7-4-2009 at 10:53 AM

It's been said that "Solar batteries never die - they're always murdered first..."

The most common mistake we see in solar installations is too many batteries...

Bob and Susan - 7-4-2009 at 11:01 AM

this is true BUT...
you MUST have ENOUGH :light:

i see too many people with lots of solar panels but only a couple of batteries
then they wonder why they dont have enough power to run the 300 watt big screen TV :lol:

dont buy small batteries
the load is too hard on them

you need LOTS of water space between the cells and plates

and dont think that just because you have solar its done
it takes work to keep the system running correctly

BajaRob - 7-5-2009 at 11:06 AM

Everyone has a right to their opinion regarding large L-16 size vs small T-105 size batteries. I have lived in a solar home for 8 years and installed and repaired over 30 systems other than my own. After three of my my neighbors had their L-16 battery banks fail at three years I would not consider using them. Two of them had professional monthly maintenance so that was not the issue. With monthly maintenance including cleaning, equalizing and topping off with water, the smaller batteries should last 8 years or more. No brainer. Energy Star appliances are a must. Our new Sony 32" flat screen only uses 135 watts. Our refers use just 1 kw.

[Edited on 7-6-2009 by BajaRob]

[Edited on 7-6-2009 by BajaRob]

MitchMan - 7-5-2009 at 12:25 PM

How much would it cost today to purchase and install a proper solar system in a 900 sq ft cinder block house in La Paz? Could this installation actually support the power required for minisplit air conditioners, a 27 inch TV, and normal inside and outside lighting?

[Edited on 7-5-2009 by MitchMan]

I have almost $18,000.00 total -complete

beercan - 7-5-2009 at 12:43 PM

Quote:

Krico
How much does a system like this cost, +/- ?

It could ---$$$$$$$$$$$$$$$$$$

beercan - 7-5-2009 at 12:45 PM

Anything is possible ----I bought all my equipment from Arizona Wind & Sun

Quote:

by mitchman
Could this installation actually support the power required for minisplit air conditioners, a 27 inch TV, and normal inside and outside lighting?

Bob and Susan - 7-5-2009 at 12:57 PM

"Our new Sony 32" flat screen only uses 135 watts"

you sure...

sony 32" 150watts

speakers 10 watts

tv box 10 watts

it all adds up...total 170 watts

still...pretty good :light:

nice choice
i wish i had purchased a bigger tv

Bob and Susan - 7-5-2009 at 01:00 PM

$18k should include

8 - 175 watt panels
charge controller
8 - t16 420 amp batteries
all wires
nice set up installation
and 3500w inverter

you're right on the money #$$$$

Bob and Susan - 7-5-2009 at 01:01 PM

no solar system i know of
can support the mini-split air conditioners

if you find one TELL ME FIRST!!!

MitchMan - 7-5-2009 at 01:20 PM

$18,000 USD...wow, that's expensive! It would take well over thirty years to recoup that cost, never mind the additional cost of upkeep.

I guess the reason for going solar is to be green for conservation's sake alone or as the alternative to a gas powered generator if you don't have access to city electricity.

bajalou - 7-5-2009 at 01:37 PM

Last year Solar Express, a company in San Felipe selling/installing/maintaining solar systems quit handling Trojan L16 batteries as they had a very high premature failure rate. Trojan Battery co installed a set at a friends place ant no cost to my friend as a test. They assured themselves that the total system was in good shape and the panels were adequate for the batteries and load. Haven' heard any more and don't know how long the test is supposed to last. But Trojan agreed that there were problems with the batteries.

Russ - 7-5-2009 at 01:59 PM

Isn't that nice,bajalou. I've bought over 30 L-16's and they, Trojan, never once admitted they had a problem! Now at over $300 per I'm gonna have to find a reasonable alternative. Absolutely not Trojan. My newest 8 are going on their 3rd year. Hope I get thru the summer! Averaging about 5 years.

Paulclark - 7-5-2009 at 02:09 PM

You cannot economically run a mini split on a solar system. A small 1/2 ton window unit uses 5 amps at 110 volts which equals 120 amp hours over 24 hours (running 100%), which equals 1200 amp hours at 12 volts. A 100 watt panel produces about 45 amp hours per day in the summer. So you need 26 -- 100 watt panels to run 1 small AC unit at 100% 24 hours per day. --- if my math is right???
2600 watts of panels at todays price is about $9,000 plus batteries, inverter etc.
I do run a small AC unit in a small insulated bedroom at night, but I watch my comsumption carefully and need to run my generator every couple of days so I don't overtax my system.

ArroyoTaxi - 7-5-2009 at 05:21 PM

As usual, the Q&A on this forum is just a goldmine of excellent information. Thank you to everyone for sharing their experience and knowledge.

k-rico - 7-6-2009 at 08:58 AM

Quote:

Originally posted by MitchMan
$18,000 USD...wow, that's expensive! It would take well over thirty years to recoup that cost, never mind the additional cost of upkeep.

I guess the reason for going solar is to be green for conservation's sake alone or as the alternative to a gas powered generator if you don't have access to city electricity.

Yes but beercan's $18K system is running a refrigerator, two freezers, and a water pump, four electric motors. They use a lot of juice, much of it turned into heat and wasted. Living a hydrocarbon fueled lifestyle on solar panels is expensive.

Plus covering a roof with roofing materials and then covering the roofing materials with photovoltaic panels is perhaps one too many coverings. If the roofing materials themselves produced a little juice when the sun is shining, and everybody used them, a considerable amount of electricity could be pooled and distributed. That's the direction things are going.

Invest in rare earth elements (as in the Periodic Table). All the new solar technologies, including wind generators, solar panels, batteries, and electric vehicle motors use these rare elements. Be prepared for the "rare earth cartel". China has the largest known deposits. Unintended consequences.

Either go without or run a generator!

beercan - 7-6-2009 at 04:49 PM

The choices were clear--and the costs of buying a good generator and running it many hours each day ---, it was clear to me that the solar would pay off..........

Quote:

by mitchman
$18,000 USD...wow, that's expensive! It would take well over thirty years to recoup that cost, never mind the additional cost of upkeep. I guess the reason for going solar is to be green for conservation's sake alone or as the alternative to a gas powered generator if you don't have access to city electricity.

TMW - 7-6-2009 at 05:09 PM

Anyone using a wind generator to supplement the solar? I don't have either just courious.

BajaWarrior - 7-6-2009 at 05:45 PM

Quote:

Originally posted by TW
Anyone using a wind generator to supplement the solar? I don't have either just courious.

My next door neighbor had one for a time until it threw a bearing.

Pros: charging at night(when there is wind) charging during daytime (usually a breeze at least)

Cons: (For me) the damn thing could get pretty noisy on warm nights with the windows open. Also it has a braking feature that was very noisy when the rpm's got too high.

I like panels and fresh batteries.

Russ - 7-6-2009 at 06:06 PM

Quote:

Originally posted by TW
Anyone using a wind generator to supplement the solar? I don't have either just courious.

Almost every one here with a serious solar system has a backup generator. I hate the noisy things! But, of course, I have one.

The most popular one is the Honda EU3000 ( http://www.hondapowerequipment.com/products/modeldetail.aspx... ) . Quiet and will run an AC unit at night and charge the battery bank as a bonus. Anyone running a generator PLEASE! consider you neighbors!

BCSTech - 7-6-2009 at 06:34 PM

We always recommend installing a generator to run air conditioning. It doesn't make economic sense to buy a solar system built to run A/C since it's only needed a few weeks or months out of the year. The rest of the time, your over-built solar system would be idling with excess power that can't be used, or stored for hot months when it's needed.

BTW, Hondas are good portable generators but we always recommend Kohler propane-fueled power plants especially when powering A/C. The smaller, portable generators all too often fail prematurely. Kohlers carry a warranty for use as a solar backup. A 17RES Kohler will start and run 5 tons of A/C. Plus you have a good, solid backup when the sun's not there. Stay away from Onan or Generac.

Power plants can easily be setup to auto-start with most modern Xantrex and Outback inverters when the batteries need help. You can also program in a "quiet time" to help keep peace with your neighbors.

Russ - 7-6-2009 at 07:32 PM

Alan's right. Propane would be nice down here and I think the Honda has a carb kit for propane. I just looked at the Kolher generators and the 8.5 propane would be enough for most applications ( http://www.kohlerpower.com/residential/detail.htm?sectionNum... ). They say they're quiet at 65bd

Bob and Susan - 7-6-2009 at 07:37 PM

propane is good and clean except...

you NEED a BIG tank
maybe another $1000usa

and

you are at the mercy of the propane company to fill

and it's STILL $$$ expensive to run

gas and diesel stink

BCSTech - 7-6-2009 at 08:11 PM

ANS: Buy the biggest propane tank you can afford.

Many use wind generators--

beercan - 7-7-2009 at 07:28 PM

in fact that is my next purchase this fall. I already have a diesel 6500 Yamaha generator.

Quote:

by TW
Anyone using a wind generator to supplement the solar? I don't have either just courious.

Bob and Susan - 7-7-2009 at 08:17 PM

beercan

before you buy a wind generator...

go to a house that has one...then

set up a chair and listen

if you can stand the whoosh whoosh

then buy one

oh yea mabe take your neighbor and get his blessing

teadust - 7-7-2009 at 08:18 PM

Quote:

Originally posted by Bob and Susan
no solar system i know of
can support the mini-split air conditioners

if you find one TELL ME FIRST!!!

Have you looked at the SolCool or the Solar AC systems?

Bob and Susan - 7-7-2009 at 08:20 PM

yes...they dont do what they say they do

i passed... you should too

the numbers dont add up

BajaGringo - 7-7-2009 at 08:21 PM

Quote:

Originally posted by Bob and Susan
beercan

before you buy a wind generator...

go to a house that has one...then

set up a chair and listen

if you can stand the whoosh whoosh

then buy one

oh yea mabe take your neighbor and get his blessing

To be fair you need to do some homework as well. Some wind generators are quieter than others, just like gasoline generators...

Already did home work

beercan - 7-7-2009 at 08:30 PM

There are about a dozen here and very little noise !!

Bob and Susan - 7-7-2009 at 08:32 PM

i'd love to use a wind generator but solar is sooo nuch quieter

if i could put it a 1/2 mile away...let me think on this...

i turned on a fan right now...it made noise

research over

my conclusion : anything that spins in the air has resistance and makes noise

BCSTech - 7-8-2009 at 05:21 AM

Quote:

Originally posted by Bob and Susan
yes...they dont do what they say they do

i passed... you should too

the numbers dont add up

Agreed. We looked at these, too. But there was too much "hype" around them, they were super expensive, and the companies hadn't been out there long enough to have any kind of reliability established.

The most efficient A/C units I've ever seen are 9,000 BTU, 26 SEER Fujitsu mini-split heat pumps drawing 624 running watts cooling. But even with that, you would probably need at least 1,000 watts in panels just to support the A/C unit if you were running it for anything more than a few hours a day.

larryC - 7-8-2009 at 07:43 AM

I have been off grid here in BoLA for 11 years now and have seen every type of solar/hybrid system imaginable, from small (2 flashlite batteries and a candle) to large (A garage full of Absolyte ll agm batteries, wind generators, 2 Bergey 1kw wind generators, gas and diesel generators and a conglomeration of solar panels) and the general consensus is that solar panels are by far the most reliable, all the other methods of harvesting power incorporate rotating machinery and will break sooner or later. If you enjoy tinkering with and fixing things (as I do ) then that will not be a problem for you. If you are not a tinkerer then solar panels need the least maintnance, just make sure you mount them well. One thing that I did was to make a tracking mount for my solar array, it follows the sun all day long and then after dark it resets itself to the east and is ready for the next day. It lets my 1100 watt array harvest as much power as if it were a 1500 watt array. Yes the tracker incorporates rotating machinery but sinse I built it I know how to fix it, and I enjoy it.
Good luck with your system,
Larry

snowcat5 - 7-8-2009 at 10:00 PM

We added a Southwest Wind Systems 200-watt Breeze wind gen. to our small solar system last December. It is a great addition, pretty quiet when operating and is mounted on our roof with the additional mounting kit and a twelve foot tall pipe. Often on stormy, cloudy Winter days, this wind gen. is producing volts when the panels are barely charging. The Breeze is the quietest wind gen. I know of and is often used on sail boats where vibration and noise can be a serious problem. The Breeze is available in a Sea-side version and different voltages. Although I sound like a Breeze salesman; I'm not, just like the product and technology.

Russ - 7-9-2009 at 06:12 AM

snowcat5 ~ This wind gen. is the one many folks tried here about 8 years ago. It has evolved into a pretty good product. Much quieter but still has a noise, almost a howl under certain windy conditions. The price is about the cost of one solar panel without the mounting hardware.

wind-sun_2057_6620392.jpg - 6kB

k-rico - 7-12-2009 at 01:47 PM

Solar Nomads,

Next Sunday I'll be in San Diego and I want to buy a solar panel for my truck camper. It won't be permanently mounted anywhere. I'll put it on top of the camper when I want to. Perhaps on a tripod pointed correctly. I'll also need an inverter.

I'll be using the panel to charge a deep cycle 12V marine battery. With the inverter connected I'll be charging a laptop computer and a Sony eBook reader with the battery, let's say worst case on a daily basis assuming daily max solar input. The eBook reader just sips electricity and the computer is a Dell netbook (no hard drive).

Is this a reasonable plan? If so, what are the specs for the appropriate panel and where could I find one on Sunday in San Diego?

Thanks

[Edited on 7-12-2009 by k-rico]

Bob and Susan - 7-12-2009 at 02:53 PM

trouble is solar panels come in 2's

if you ONLY buy one you pay extra

sunday??? call and make an appointment for
monday

TEQUILA4EVER - 7-21-2009 at 01:47 AM

hi -

am rolf - solar outback specialist for some decades .

anybody who needs info about solar ,warmwater and wind is free to ask .

am happy to reply to all serious inquiries .

cheers

noproblemo2 - 7-21-2009 at 09:21 AM

Welcome rolf, bout time you piped in here!!!!!!!!

teadust - 8-9-2009 at 03:38 PM

I thought of this thread after reading about what looks to be an exciting and promising solar battery technology - a ceramic disc the size of your hand that can store 20-kilowatt hours:

Tiny Battery Traps Solar Power to Run an Entire House

Ceramatec is quite a company; this will something to keep an eye on when it hits market testing in a couple years...

DENNIS - 8-9-2009 at 03:43 PM

Ceramatec...........Here's some additional info:
--------------------------------

http://solar.coolerplanet.com/News/8070901-ceramatec-develop...

ncampion - 8-9-2009 at 04:03 PM

That's amazing..... I want one!! Now if we can combine this kind of storage with this kind of power generation, http://www.nanosolar.com/solar may really take off. I can see my off-grid house is just a few years too early.

.

BCSTech - 8-9-2009 at 04:20 PM

From the coolerplanet article:

Quote:

The battery runs on a sodium-sulfur mix, which is reportedly more energy intensive than typical lead-acid batteries, and has a 92-percent charge/discharge rating, allowing grid-tied solar energy users to store energy from their solar panels during off-peak hours (typically midnight to 7 a.m.) and use them when kilowatt-hour electricity costs soar during the day.

How do you store energy from solar panels during off-peak hours "typically midnight to 7 AM???"

KAT54 - 8-9-2009 at 06:16 PM

Moonbeams, you silly goose.

ncampion - 8-9-2009 at 08:51 PM

Quote:

How do you store energy from solar panels during off-peak hours "typically midnight to 7 AM???"

That's what batteries do. This is essentially a new generation electrical storage device - formerly know as a battery.

.

Lunar Panels

MrBillM - 8-9-2009 at 09:24 PM

..........."allowing grid-tied solar energy users to store energy from their solar panels during off-peak hours (typically midnight to 7 a.m.) and use them when kilowatt-hour electricity costs soar during the day".............

Gotta go with BCSTech on that one. The sentence doesn't make sense. Storing energy FROM the Solar Panels would have had to occur PRIOR to midnight (Like During Daylight), of course, regardless of anything else. What they are likely trying to say is that they store energy from THE GRID during the off-peak hours.

If they can't get their story straight, what else ?

BCSTech - 8-9-2009 at 10:24 PM

Also, why would "dishwashers or combined TV/computer operations" be excluded? Does that mean air conditioners, pool pumps and electric heaters are "OK?" Makes no sense. Watts is watts.

Diver - 8-10-2009 at 07:20 AM

Quote:

Originally posted by k-rico
Solar Nomads,

Next Sunday I'll be in San Diego and I want to buy a solar panel for my truck camper. It won't be permanently mounted anywhere. I'll put it on top of the camper when I want to. Perhaps on a tripod pointed correctly. I'll also need an inverter.

I'll be using the panel to charge a deep cycle 12V marine battery. With the inverter connected I'll be charging a laptop computer and a Sony eBook reader with the battery, let's say worst case on a daily basis assuming daily max solar input. The eBook reader just sips electricity and the computer is a Dell netbook (no hard drive).

Is this a reasonable plan? If so, what are the specs for the appropriate panel and where could I find one on Sunday in San Diego?

Thanks

[Edited on 7-12-2009 by k-rico]

When you get your panel, buy a 25', 10 ga or larger extension cord.
Cut off one end with about 2' of wire and wire this to your battery permanently so the plug is accessible.
Wire the other end to you panel/charge controller so you can plug it in and place it where you want around the camper.

When our mobile panel isn't on a camping trip, the panel is charging the battery for our electric fence charger out in the pasture.

ncampion - 8-10-2009 at 07:32 AM

Quote:

Originally posted by MrBillM
..........."allowing grid-tied solar energy users to store energy from their solar panels during off-peak hours (typically midnight to 7 a.m.) and use them when kilowatt-hour electricity costs soar during the day".............

Gotta go with BCSTech on that one. The sentence doesn't make sense. Storing energy FROM the Solar Panels would have had to occur PRIOR to midnight (Like During Daylight), of course, regardless of anything else. What they are likely trying to say is that they store energy from THE GRID during the off-peak hours.

If they can't get their story straight, what else ?

After re-reading the article, I agree some things in it don't make sense. Probably written by a nimrod that doesn't really know what they are talking about. Keep in mind that this is an article, not literature published by the company. Still looks like breakthrough technology.

BCSTech - 8-10-2009 at 07:38 AM

Quote:

Originally posted by DiverWhen you get your panel, buy a 25', 10 ga or larger extension cord.
Cut off one end with about 2' of wire and wire this to your battery permanently so the plug is accessible.
Wire the other end to you panel/charge controller so you can plug it in and place it where you want around the camper.

When our mobile panel isn't on a camping trip, the panel is charging the battery for our electric fence charger out in the pasture.

If you're going to run without a charge controller, better make sure that panel is matched pretty well to your battery voltage and that you disconnect when the battery is full or you could end up frying the battery.

Out of Control

MrBillM - 8-10-2009 at 09:29 AM

Back in the Solar Stone-Age, the Arco controllers I was using would often not bring the Batteries to full-voltage even though the panels were capable of doing so.

I wired a bypass switch to allow direct charging. Worked great and I used it for years before uggrading the panels and going to a Trace Controller.

I had installed a similar system for my OLD next-door neighbor and when he heard what I had done on mine, he had to have one. I explained to him that bypassing the controller meant that he HAD to watch the battery voltage and not let it exceed 14.2 or so because he'd ruin the batteries.

NO need really to see where that went. I'd go over to his house and find the batteries up in the 15s and his answer was " I want to get as much in there as I can before dark".

He was later to complain about his shorter Battery life.

Surprise.

Diver - 8-10-2009 at 03:38 PM

Quote:

Originally posted by BCSTech

Quote:

Read again BStech;
I said connect to panel/charge controller.
I glued a 10A charge controller to the back of this 85 watt panel (5.5 amps) so there are no issues.

I have run panels in the old days without charge controllers; you need to have some way to check the charge so you don't cook the batteries.