getting ready to go solar

[garymedina]

we are getting ready to buy our homestead right after christmas. we are going to be in southern missouri most likely and are considering solar power for all our electric needs. starting with a travel trailer, but will be building a house soon and would like to run the whole homestead on solar. would like to know what would be the best voltage to go with for the long term. and any advice on types and brands of panels, batteries, controllers, and inverters would be greatly apperciated. we'll have higher than normal electric needs because of the kids and would rather have to much than not enough. thanks for the help

[Anon001]

will be building a house soon and would like to run the whole homestead on solar. would like to know what would be the best voltage to go with for the long term.

With 24v you can run further distances but, there are very few appliances and such that are available in 24v. With 12v, the wire runs are shorter, but you find just about anything you want in12v.

and any advice on types and brands of panels, batteries, controllers, and inverters would be greatly apperciated.If you don't go with the high dollar solar type batteries, the next best option is the golf cart, deep cycle, 6v battery. Stay away from automotive batteries and marine/rv batteries. The marine/rv battery almost always say they are deep cycle, but they aren't. They are a hybrid between deep cycle and automotive.

we'll have higher than normal electric needs because of the kids and would rather have to much than not enough. thanks for the helpThat's where your attitude toward electrical needs may need to change. The biggest disappointment for people on solar is when they and the children don't scale back on consumption. To be happy with solar, you and the entire family have to be on the same plane. Everyone has to learn to cutback on the electrical needs. Otherwise, you will spend a fortune in solar trying to mimic the utility unlimited supply of electricity. So, I would begin now teaching the kids they must conserve.

The first step in planning an alternative energy is to sit down and write out everything you use, how many hours per day on average, and how much every item uses in electricity. You MUST know exactly how much electricity you will need.

I hope that helps. I know others, especially 12vman, will jump in.

I've been 100% off-grid since May 1998 and I don't regret it. I also don't regret paying a utility bill every month.

Good luck,
Paul

[kawalekm]

Hi Gary
Maybe for your situation going whole solar is NOT going to work for you. When you say that your power needs will be high because of your children, I'm assuming that you mean because of them running things like TV/games? Or is it lots of lighting at night for studying students? Typical off-grid homeowners have to learn to be very, very frugal with power consumption out of necessity! That might not work with kids that really don't understand the concept of conservation.

Is there any wind at your location? Shortfalls in solar power can sometimes be compensated by wind. Our cabin is on a ridgetop, so on those days that it's cloudy and stormy, the lack of sun is made up by high winds. Perhaps a combination solar/wind system might better meet your needs. Your charge controller will have to be different if you have both solar AND wind. Solar only controllers can't handle the voltage changes that wind generators vary by.

Perhaps the best system for you would be combination solar/wind/generator source. You'll be able to run the generator on those cloudy, windless days when no other source of power is available.

In any case, I would start in the library or a book store and get a few books on home power production. Start by reading up on the available literature, then start searching the net to compare prices.

[PowerGuy]

In additional to sever power and energy (not the same thing, btw) reductions, and necessary very tight load management requirments, mentioned by others alreay, you need to think your system through to make sure that it meets your needs. The DC voltage is not overly important unless you plan to use low voltage DC appliances, of which there are very few, are expensive, and are only in 12 volts for the most part. Your strings from the PV array can be high voltage DC (100 to 150 vdc) and the output from the charge controller can be selected for 12, 24, 36 or 48 volts DC depending on how you want to wire up your battery bank. If you use an inverter to power standard AC applicances, you simply match your battery bank voltage to your inverter, either 12, 24, 36 or 48 vdc. Since the inverter and the battery bank can be located in close proximity, the issue of cabling is not a major consideration. In general, the higher the voltage, the smaller the cable for any given power level. It is more important to determine your power and energy needs and one way to do that is to simply look at your monthy utility bill. Divide your total KWH by the days for an average of KWH/day. Run an experiment to see how low you can go with life style changes and then use that data to see if you can afford the PV system to provide that level of power and energy. You can monitor your instantaneous power consumption by timing one revolution of your utility meter. Multiply the Kh parameter on your meter (example: 3.6 or 7.2, etc.) by 3600 and divide by the seconds per revolution for an instant power consumption level. With average energy data in KWH/day, and a maximum instantaneous power in KW, you can size a PV system to meet your needs; or you can use the data to change your lifestyle even more! At least you will have some basis for the design. We understand that PV systems that are sized to meet the normal needs of a family such as you describe could easily be as large as 10 KW nominal, and thus very expensive. We are not off grid, but are prepared to be so if there is no grid available. We elected to use a 12 vdc inverter and battery bank so that we could use low voltage 12 volt lighting direct from the battery bank (also, our well water boost pressure system has 12 vdc capability). Our other critical loads like freezers are conventional AC. Our system is only 1 KW on tracking arrays, and thus is quite reasonable in terms of cost. The trade off is that under a grid outage situation, we are in an emergency power rationing situation!

[garymedina]

we have already started to teach the childern to conserve energy. we don't watch television or play video games. most of the reason i think we would need more power is because of the number of kids (6) and the construction that will be going on. i already plan on having a back up generator and would appreciate any advice on a good dependable generator. would like to have a dual fuel ( gas/propane ) if that is practical. want to have atleast 10000 watts on the generator. the kids are already catching me leaving the light on and reminding me to turn it off when i leave the room. i plan on having a 500 gal propane tank and a 100 gal gasoline tank on the homestead. i plan on making the house super effiecient. and would like to stick with 12v everything and inverter for the 110 stuff. i have been in construction for 15 years and i can build anything ( or so my kids say ). i plan heating with wood primarily and cooking with it some. want to be able to run a small a/c unit during the hottest times in the summer in one or two rooms. we live in georgia now but will be homesteading in missouri.
so just a few more question.

1. the runs you guys are talking about, are they the runs from the solar panels to the house or from the breaker/fuse panel to the actual load.

2. how about that generator? dual fuel? brand? 10000 watts enough or to much?

3. can an small a/c be run on say a $10,000.00 system?

4. any good books yall can recommend to get me started on the planning stage?

5. can batteries be stored in the house? gases?

thanks so much for the respones and the advice
look forward to talking to yall more about the homesteading.

[12vman]

"any good books yall can recommend to get me started on the planning stage?"

Here's (http://sunelco.com/resident.aspx) a PDF form that you can fill out and figure your loads and to give you an idea of how big of a system you'll need to supply what you want.

[PowerGuy]

One of the best sources for self sufficient living is Home Power Magazine (www.homepower.com). They have editorily signed onto man caused global warming, but with the exception of that unfortunate lapse in scientific judgement, it is a good source of information. You should subscribe, and then will have on line access to their extensive archives of past articles. A search on that data base will essentially provide you with all the education you will need. The questions that you are asking are specific and will depend for the most part on your actual conditions.

I can address a couple of your questions, in general terms, naturally based on our experiences, which may not match others on the forum:

1. 10,000 watts for a stand by generator, for either construction purposes or subsequent homestead back up power is probably too large, and thus too expensive. Dual fuel is also going to be expensive and in that size range will be essentially a full residential/commercial back up unit with automatic transfer switch capability. In our opinion, the smallest good quality 120/240 vac unit is sufficient, on the order of 6 kw. We recommend 220 v so that you can run a small MIG welder if needed. And, in that size range, you can get one with an internal fuel tank of about 5 gallons or so. We used a 2.2 kw generator during construction of our 3300 sf home on 120 acres, and subsequently bought a 6 kw unit for back up and to run a small MIG welder at remote locations on the property. How many power tools can you operate at one time?

2. We recommend that you forget A/C, unless you want to run your generator 24/7. Even a small unit will drain your batteries on a cloudy day or use most of the output from your array on a sunny day. Cooling should be addressed in your home design, i.e, earth bermed, earth sheltered, shaded, ventilated, Insulated Concrete Forms (ICF) construction, etc.

3. $10,000 invested in a PV system will buy you varying amounts of final system depending on your level of DIY and the specfic design. In general, panels are running about $3 to $5 per watt these days, depending on make and quantity (one at at time or by the pallet). A rule of thumb is that you double that for installation and aux. systems (inverters, batts, wire, enclosures, etc.). So, a 2 kw system would likely cost about $8000 to $10,000. A 2 KW sytem on a fixed mount would provide basic or emergency UPS services, and provide power for construction (one power tool at a time!) but that would be about it. Ours is a 1 kw system on twin tracking arrays (due to extremem wind loads) and we spent over $10,000, using no outside professionals or contractors at all. Ours is designed specifically for UPS and emergency operation, not to be permanently off grid.

4. The "runs" that we were referring to were from the PV arrays to the charge controller. Ours are two strings over 150', are number 10 solid copper wire, run at about 80 vdc and 4.7 amps (MPPT) and 110 ocv. We have very limited items on 12v, like critical lights and water pressure booster pump in the mechanical room, and the rest is 120 vac on an inverter. Our battery bank is connected by VERY short runs of multiple #4 battery cable, and our draw down on the bank is limited so as not to stress the batteries. We use sealed AGM (Absorbant Glass Mat) batteries, so that there is no venting issue, and since they will not be routinely cycled.

[garymedina]

hey guys thanks so much for all the post and advice.
we are counting down the days until we move to the homestead.
i kbow i'll have a million ? for yall and look forward to talking to all of you more.

[Travis]

I do not have any personal experience in solar energy or what systems to use , I am however studying energy management and am currenttly in my 1st term of 6 terms so i am still green but this is what I have been taught and some may help and others may not.

1) You should install photothermal before photvoltaic, water heating takes alot of energy. In winter you may not be able to use the suns power so you could put a heat exchange on/in a wood burning fireplace and heat your water that route. Also besides just water heating you can do radiant floors thus heating your home alot easier.

2) Orientate the building with the long side north/south with maximum glass on the south and least on east.

3) Maximize solar gain by planting trees to shade in summer and go dormite in winter. Windows or solar tubes to bring light in during the day so you do not need lights on using electricity.

[Prairie]

How much electricity does the inverter waste/consume while dormant and while converting to run appliances? I currantly only have a camper on strictly solar, and have a very small (75W, I don't need anything bigger yet) inverter. I don't have a need for the inverter yet, but would it make sense to use it to run flourescents instead of the 12V incandescents? (as an example) Also, what about a 12VDC to 24VDC converter? Anybody have any experience with them?

[Anon001]

1) You should install photothermal before photvoltaic, water heating takes alot of energy. In winter you may not be able to use the suns power so you could put a heat exchange on/in a wood burning fireplace and heat your water that route. Also besides just water heating you can do radiant floors thus heating your home alot easier.

Travis,

I have to disagree. Photovoltaic will provide the electricity that you can't get from photothermal. Am I correct? Also, most people on solar don't use radiant floor heating because the pump to circulate the water uses additional power.

Most rural people will use propane if they are not in an all electric house. Propane is not too expensive. For cooking, water heating, and refrigerator, I went 14 months on 200 gallons.

So, I would have to say if it's new construction, so photovoltaic first. Use propane for the other items that photovoltaic would be too costly to operate. Heat with wood.

Paul

[Travis]

Travis,

I have to disagree. Photovoltaic will provide the electricity that you can't get from photothermal. Am I correct? Also, most people on solar don't use radiant floor heating because the pump to circulate the water uses additional power.

Most rural people will use propane if they are not in an all electric house. Propane is not too expensive. For cooking, water heating, and refrigerator, I went 14 months on 200 gallons.

So, I would have to say if it's new construction, so photovoltaic first. Use propane for the other items that photovoltaic would be too costly to operate. Heat with wood.

Paul



you are correct if you are not grid tied and able to use propane then that would be the way to go. I still would still use solar thermal for all those months that you can heat water via the sun, it will save money and propane.

[12vman]

How much electricity does the inverter waste/consume while dormant and while converting to run appliances? I currantly only have a camper on strictly solar, and have a very small (75W, I don't need anything bigger yet) inverter. I don't have a need for the inverter yet, but would it make sense to use it to run flourescents instead of the 12V incandescents? (as an example) Also, what about a 12VDC to 24VDC converter? Anybody have any experience with them?

"How much electricity does the inverter waste/consume while dormant and while converting to run appliances?

When an inverter is on but not being used, there's a small amount of current consumed by the electronics of the unit but it's usually pretty small. (Milliamps) It's called a "stand-by" load. The larger the inverter, the larger the stand-by draw.. Usually..

A 75 watt inverter will have a small draw so it would be better if you shut it down when you're not using it, especially if you have a small PV system. Normal operating losses can be expected in any inverter but they are usually small. (5%)

"I don't have a need for the inverter yet, but would it make sense to use it to run flourescents instead of the 12V incandescents?"

In a small system, the best way to avoid losses is to operate anything you can directly from the battery. Anytime you convert anything there's going to be losses.

"Also, what about a 12VDC to 24VDC converter? Anybody have any experience with them?"

What do you want to operate at 24 volts? When you double your voltage, you double your load to the battery.

[PowerGuy]

I do not have any personal experience in solar energy or what systems to use , I am however studying energy management and am currenttly in my 1st term of 6 terms so i am still green but this is what I have been taught and some may help and others may not.

1) You should install photothermal before photvoltaic, water heating takes alot of energy. In winter you may not be able to use the suns power so you could put a heat exchange on/in a wood burning fireplace and heat your water that route. Also besides just water heating you can do radiant floors thus heating your home alot easier.

2) Orientate the building with the long side north/south with maximum glass on the south and least on east.

3) Maximize solar gain by planting trees to shade in summer and go dormite in winter. Windows or solar tubes to bring light in during the day so you do not need lights on using electricity.

Travis,

Congrats on your course of study in energy management.

On your first point, the installation of solar thermal or solar PV will likely depend more on the specific persons priorities. Solar thermal is inherently more efficient since it can replace fossil fuel sourced energy, or even electric (which is mostly fossil fuel also, but even more inefficient!). So, in terms of eficiency, solar thermal is first, and that is how I approach my systems. However, I have seen many folks go PV first also for various reasons. If you have limited space for panel installation, hopefully all ground mounts, then thermal may be the first logical choice. You have to be careful about fire box heat exchangers since there are inherent problems based on potential steam generation (cooling water hitting a grate that is at 1000F), thermal shocks, over cooling the stove and thus putting out the fire, corrosion and deposition in the tubing (hard potable water in a hot HTX), etc. I have not recommended it for my clients unless they are particularly talented technically and can devise and maintain a fairly complex control and safety system.

On your second point, I think you meant to say that the long axis oriented east west is best? The most sucessful designs that I have implemented actually have a "bent" orientation, with half the house facing SE and the other half south, with, of course, lots of glass. These days you have to be careful about the very popular "Low E" glass! On one recent home, we had to insist on hard to find normal glass in a sun space that was intended to "over heat", and allowed Low E glass on adjacent occupied spaces with large bay windows facing south. The sunspace reaches 90F+ and the other spaces remain comfortable. The Low E glass cut solar insolation by about 80% according to our solar meter, not really the intent for a "solar" house! We are also aware of some DIY "solar" homes that were glazed 100% in Low E glass (probably based on some salesman's pitch) that do not perform well at all.

Your third point regarding trees has not worked well in our experience. Dormant trees on southern exposures appear to effectively block significant insolation in winter and we have found that properly desgined overhangs are more effective for summer shading. Trees on the other 3 exposures are probably a good idea, however. Light tubes also might be effective, but we have been as sucessful with large south facing glass areas, light colored walls and ceilings, and open spaces to trasmit solar illumination deep within a home floor plan.

Keep up the curiousity on matters related to energy, for these issues are lifkely to increase in importance down the road!

[PowerGuy]

Also besides just water heating you can do radiant floors thus heating your home alot easier.

Travis,

I should have mentioned in the previous post that your comment about radiant floor heat is also very important! For active systems, of course, radiant transfer to the occupied space is the most efficient method by far. It allows temperatures as low as 95F to 100F to effectively heat living space since the room air temperature can be lower and still be comfortable. As you may know, if the collector working temperature can be kept as low as possible, thermal collectors operate at a higher efficiency. For medium temperture collectors, even with selective surfaces, the difference between running at 150F and 100F can be dramatic. Radiant floor heat should also then be combined with a mass storage approach. We have had very good success using 4" to 6" of heavy structural concrete in floors, with PEX tubing embedded. On a 24 hour cycle, the storred heat energy usually precludes any back of heat. There is an excellent article in the November issue of Plumbing Engineer, entitled, Solar Solutions: Bristol's six principles of good solar hydronic design, that is closely on point on this topic.

[PowerGuy]

Here is the link to the Plumbing Engineer article noted in my last post:

http://www.plumbingengineer.com/pdf/pe11_2009.pdf

[Prairie]

Thanks for the info, 12V. I have a 24V well pump, and a fan that might come in handy if I have 24V already to run the pump.

[NotSoFast]

"any good books yall can recommend to get me started on the planning stage?"

Here's (http://sunelco.com/resident.aspx) a PDF form that you can fill out and figure your loads and to give you an idea of how big of a system you'll need to supply what you want.
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[12vman]

OOps.. They changed their site! Here's an option..

http://www.siliconvalleypower.com/res/?sub=apchart

http://www.solarexpert.com/Pvload.html

[firegirl969]

I need to bounce off my ideas and those I gleaned from chatting with Paul about our upcoming homestead solar power project. DH and I plan to put all extra available funds into completing the solar project this year. This will add a whole new level of self-sufficiency for us. So far, DH and I have two Koceyra panels that total 250 watts. We also got a new fuse box, some fuses, and cheap charge controller of some kind and the book Paul recommended, The Independant Solar House (I think that is the name, I can't go look at it right this second). We also bought a 1500 watt modified sine wave inverter. Do we need an inverter this big or should I return it and get a smaller one? We are looking to buy 8 Interstate deep cycle golf cart batteries, the ones that Paul uses and recommended. We will stay on-grid as long as we can afford it or it is available.

Our future plans are for either a Hotpoint 16 cu. ft. energy star refrigerator with a daily rating of .88 kWh/day or a Serval propane refrigerator and an energy efficient small chest freezer which uses about the same as the hotpoint fridge or a propane chest freezer that will use about 2 gallons of propane a week ( what are ya'lls viewpoints on these two alternatives?) Also, we plan to change over hot water over to a tankless LP hot water heater which is rated for 1 lb propane usage per day. We already heat with a wood stove, can on a 3-burner propance cook-top, and have a 4 burner propane stove with a 100lb cylinder and a 110 gallon tank. We also have a 225 gallon propane tank we plan to fill up when and if summer rates ever kick in. I plan to get rid of the worn-out electric washer and dryer and get a James washer and continue to use my clothesline. We also plan to get a 22" LCD 12 volt tv and 12 volt DVD player. We will charge the rechargeable batteries and flashlights with the system if the grid goes down. If things get so bad that we can no longer afford to have any grid supply, we have also decided to give up internet and satallite tv services, we may give them up sooner if need be.

For power for the electric well, we have a 4000 watt Coleman generator that came with our camper many years ago but works well. We are also considering installing a 12 volt pump with its own inverter and solar panel and batteries in the pumphouse and putting a 1050 gallon plastic tank in the air and pumping water into it every couple of days and using gravity to feed the water to the house and barn. The pumphouse is very close to the house and about 100 feet from the barn.

Do you guys think that our 250 watt pv system will power the refrigerator if we decide on it, tv and dvd player, small radio, energy star freezer, and charging batteries and flashlights. Is there any other items we should consider adding? Thanks in advance for the advice, firegirl

[Anon001]

I'll give you my personal opinion. I'm sure there will be others that disagree. I would never opt for a refrigerator that isn't propane, unless propane costs go through the roof. A propane fridge should last the rest of your life with minimal maintenance. With the panels and batteries you have, you can easily run the TV, DVD, computer, lights, printer, etc. If you are already using propane, I think the propane fridge would be the best option.

About the freezer. If it was me, I would use less freezer space and do more canning. I have a very small freezer and about the only thing I put in it is sliced okra and ice... Every thing else gets canned.

You might also eventually check into the option for a larger propane tank such as a 500 gallon tank instead of two or three smaller ones. I know here, none of the propane companies will deliver less than 300 gallons at a time. But... the co-op will deliver less if they are nearby. Also, in this area, it is much cheaper to get the bulk delivery versus the smaller tanks filled. Right now the distributors around here are at around $1.80 per gallon.

Did you like the book? Being someone that new absolutely nothing, it was easy for me to understand when I started looking into solar.

Have you done the math on the the system you have compared to the power you will use?

Paul

[Anon001]

One other thing. Have you looked at the different brands of propane refrigerators?

You might also look at the Crystal Cold. I have one that I bought new in August 2003 that I like. I have no regrets

Paul

[firegirl969]

Yea, Paul, DH really likes the book! I got an awesome price on the Trojan T105 batteries. A gent in the town near our farm juist started selling them, and he quoted me a price of $95 a battery each. We can't beat that price anywhere from what I have seen. I have looked at the propane fridges. I kinda was thinking of going with the Serval due to the good reports I have read about it. What is the difference in the Crystal Cold and Serval?

[Bare]

I studied this a lot and I'll prob'ly get nailed for my opinion but here goes.

I've never done any home solar or anything but I have an 8750 sqft mini-storage facility and explored the possibilities of dedicating the entire roof structure to solar energy. It's ideal. All steel building, east-west lay-out, 1 in 12 slope, easy to work on and all the space I need in my office and personal storage. One problem is, 12-14 year cap rate. The other is the government subsidies. Why? When government sub's things, it drives up the costs. Sellers see huge profits and jump on the sub's as a way to off-set the increase in profits. Hence the 12-14 year cap rate.

T. Boone Pickens, an oil commodities man, wanted to put thousands of windmills up in the mid-west till he ran into the infrastructure issue. The infrastructure problem cost as much, if not more than the windmills themselves. Not a small issue and it's why the project was abandoned.

I've talked to several people who have owned windmills and they all had the same problem. Repair and maintenance. They all said they were doing alright untill the thing broke. And they break. The problem is, they are 75-100 feet in the air and it takes a specialist to fix them. I know you've heard of the high paying careers of these repairman. After the second repair, they were fixed and sold. No money made.

On a small scale, wind a solar can be utilized but there is an ever present conservation issue. I've done some gold mining in remote places and I built a 12 volt generator out of a 50 amp Motorola alternator and a 5 hp Briggs. We use 12 volt to power small recovery equipment and camp lights instead of lanterns and the generator worked excellent, well worth packing it in. I'm considering building a cabin and using it to resupply most of my electric needs which won't be that much.

In short, solar and wind need a lot of work developing some important issues. Power is not free nor is it cheap. The question is, How much do you need and what is the best way to service the need?

[Anon001]

. What is the difference in the Crystal Cold and Serval?

I don't think you can go wrong with either one. Many dealers will sell both.

One problem is, 12-14 year cap rate. The other is the government subsidies. Why? When government sub's things, it drives up the costs. Sellers see huge profits and jump on the sub's as a way to off-set the increase in profits. Hence the 12-14 year cap rate.

What is a "cap rate"?

They all said they were doing alright untill the thing broke. And they break. The problem is, they are 75-100 feet in the air and it takes a specialist to fix them.

I've rarely seen residential wind generators that high in the air. Also, most of them are more durable today. However, wind generators are not as reliable as solar panels.

On a small scale, wind a solar can be utilized but there is an ever present conservation issue.
That is with any type of electricity source. The nice thing about alternative energy is that you are not a slave to the utility companies. My payback on my system is just over $13 per month based on the life of the various components of my system.

The question is, How much do you need and what is the best way to service the need?
The best way to service it, is DIY.

It always amazes me when people comment on the "perceived disadvantages" about alternative energy when they have no experience with it.

One thing I know is that I have everything I need or want and my system costs out to about $13 per month and I don't have to work away from home to earn enough money to pay for $200 per month electric bills, plus the costs of maintaining a vehicle for that much use. I'm also not at the mercy of the utility company's very frequent power outages. With rural electric, power outages are common if you use a rural electric co-op.

Paul

[DM]

I don't think you can go wrong with either one. Many dealers will sell both.



What is a "cap rate"?



I've rarely seen residential wind generators that high in the air. Also, most of them are more durable today. However, wind generators are not as reliable as solar panels.


That is with any type of electricity source. The nice thing about alternative energy is that you are not a slave to the utility companies. My payback on my system is just over $13 per month based on the life of the various components of my system.


The best way to service it, is DIY.

It always amazes me when people comment on the "perceived disadvantages" about alternative energy when they have no experience with it.

One thing I know is that I have everything I need or want and my system costs out to about $13 per month and I don't have to work away from home to earn enough money to pay for $200 per month electric bills, plus the costs of maintaining a vehicle for that much use. I'm also not at the mercy of the utility company's very frequent power outages. With rural electric, power outages are common if you use a rural electric co-op.

Paul

Hey Paul,

The thing your missing is, not everyone pays anywhere near $200 per month for electricity... I know i've NEVER had a $60 power bill in my life, and i have a nice hobby wood shop with lots of bigger power tools ect... I lost power one time all last year, and it was because a switch on the pole to my shop shorted lol. They came out within a couple hours and found and fixed it at no cost to me. (and gave me the power pole, as they put up a new one)

Those folks that have $200 dollar power bills, sure won't be living the SAME lifestyle once they get off grid... They will be forced to make some REAL changes, and the truth is, they could make those same changes and stay on grid, and have a MUCH lower power bill, just like i do.

Also, i guess you don't consider propane a "utility" company... Personally i do, as it's just like the electric company, someone else you have to depend on that can set what ever price they want...

Most folks leave out some of the cost of being off grid, and then quote a low electric price.

DM

[Anon001]

DM.

You're lucky. In this part of the country, if you run an A/C or a Furnace, you will have electric bills of $200 or more per month. Of course, with propane for heat in this area, most of the old farm houses run anywhere from $200 to almost $1000 per month in propane, according to people I've heard complaining about it. I think you probably know how much firewood could be cut for that. A lot! LOL

I'll also add that my mother moved into the city a few years back, after she was widowed. She bought a small, newer, garden home. Her utility bills run between $200 and $300 per month and she is conservative. One light at a time, keeping the temp up in summer and down in winter, etc...

Propane can be considered a utility, but I don't think it's quite as bad. I know with the farmers co-op here, they don't "gouge". The members wouldn't stand for it. With a farmers co-op, the members have a bit more control than with an rural electric coop or a public utility.

As to the true costs of electric.... My payback of $13 per month includes everything, including the cables between batteries, right down to the fuses. I left absolutely nothing out of that.

Paul

[DavidOH]

Did you like the book?
Paul

I looked back in this thread and I could not find what book you are referring to.

Here are a couple from my shelf:
Independent Energy Guide
The Evolution of an Independent Home

Both from the Backwoods Home Bookstore.

[AlchemyAcres]

However, wind generators are not as reliable as solar panels.

That depends on location.
Location! Location! Location!

Example: Tonight at this Zip...NOAA has forecast S wind at 5mph and is currently recording S wind at 6mph....at my place on top of the mountain..currently (2:00AM)..sustained winds are S at about 15mph with gusts to 22mph!!

Is the sun shining tonight??? LOL ;)

But, there are, of course, certain disadvantages to having a really windy location. :D


~Martin

[Diavolicchio]

I considered both solar and wind for supplemental energy for a new home construction. The island where I've lived for the last 15 years just erected 3 huge wind turbines to help bring the cost of electricity down on the island. It's turned into a bit of a fiasco out here though. Apparently anyone who lives within 1/2 mile of the turbines is being driven from their homes because of the sound the turbines make. It's at such a low frequency that it reverberates through the walls of people's homes causing a steady throbbing sound about every three seconds and goes on 24/7.

I'll stick with solar. I like the low decibels it produces. :) I'm also not too keen on the idea of erecting a huge "lightning rod" near my house, the destruction of which (I believe) wouldn't be completely covered by insurance.

I'm going with a 12-panel (3.8 kW) Solar PV system which should provide around 4.9 MWh of electricity annually for the little house being built. This comes out to about an average of 412 kWh/month or 13.5 kWh/day. I've determined this will cover about 80% of my electricity needs, the remaining 20% of which will be covered by the basic $8 fee I'll have to pay to have electricity.


John

[DM]

DM.

You're lucky. In this part of the country, if you run an A/C or a Furnace, you will have electric bills of $200 or more per month. Of course, with propane for heat in this area, most of the old farm houses run anywhere from $200 to almost $1000 per month in propane, according to people I've heard complaining about it. I think you probably know how much firewood could be cut for that. A lot! LOL

I'll also add that my mother moved into the city a few years back, after she was widowed. She bought a small, newer, garden home. Her utility bills run between $200 and $300 per month and she is conservative. One light at a time, keeping the temp up in summer and down in winter, etc...

Propane can be considered a utility, but I don't think it's quite as bad. I know with the farmers co-op here, they don't "gouge". The members wouldn't stand for it. With a farmers co-op, the members have a bit more control than with an rural electric coop or a public utility.

As to the true costs of electric.... My payback of $13 per month includes everything, including the cables between batteries, right down to the fuses. I left absolutely nothing out of that.

Paul

Hi Paul,

First of all, i'm NOT "anti" going off grid... I just think that MOST times it's not what it's cracked up to be, and not as cheap as it seems either.

For instance, you are will willing to go without a LOT, to live off grid. You don't have an air cond option, you don't have a shop where you can build and fix your own tools. Perhaps you don't have a metal or woodworking hobby that requires a welder or table saw... When i want to weld, or use my impact with my compressor, it's there and it saves me a lot of money to fix things myself. If i'm too lazy to carry water from my ponds to my garden in pails, i have a electric pump and garden hose, that pumps water out of my pond for that purpose... If i want to power wash something, i use the same pump and source. If we have a hot muggy night, i can turn the air on for a while so i can sleep comfortable after working all day...

Most folks off grid buy a generator, and then run it to power the washing machine, or maybe to fill a water tank... That gen set and gas is part of the cost of electricity... So is the time it takes to do the maintance on those batts and cleaning those cables. As is the room most build to put those batts in... Some use 100 pound propane bottles, then haul them in to be filled. (you even have propane tank rent) That cost of driveing to town, adds to the cost of being off grid, and then there's the extra cost of that expensive fridge and freezer and ect. and ect.. (used fridges and freezers here are almost free) There are LOT'S of hidden cost to being off grid, and even though most folks don't mind them, they are still there and they still cost someone money and time...

Folks say "You're lucky" to me about a lot of things... I don't consider it luck, i could have bought property where electricity is expensive just like you did. I could have bought property with no tree's that i could harvest the logs out of to build with, and heat my house with. I could have bought a place with water problems ect... But i didn't, and that wasn't luck, it was buying the right place...

Anyway, if someone wants to be off grid, GREAT, just so they realize ALL of what it involves, and ALL of what they are giving up...

Anyway, great discussion, thanks for answering here...

DM

[AlchemyAcres]

I considered both solar and wind for supplemental energy for a new home construction. The island where I've lived for the last 15 years just erected 3 huge wind turbines to help bring the cost of electricity down on the island. It's turned into a bit of a fiasco out here though. Apparently anyone who lives within 1/2 mile of the turbines is being driven from their homes because of the sound the turbines make. It's at such a low frequency that it reverberates through the walls of people's homes causing a steady throbbing sound about every three seconds and goes on 24/7.

I'll stick with solar. I like the low decibels it produces. :) I'm also not too keen on the idea of erecting a huge "lightning rod" near my house, the destruction of which (I believe) wouldn't be completely covered by insurance.

I'm going with a 12-panel (3.8 kW) Solar PV system which should provide around 4.9 MWh of electricity annually for the little house being built. This comes out to about an average of 412 kWh/month or 13.5 kWh/day. I've determined this will cover about 80% of my electricity needs, the remaining 20% of which will be covered by the basic $8 fee I'll have to pay to have electricity.


John

To each his own!

Thank God they'll be taking the commercial anemometer test tower down that's next to me and there won't be any behemoth turbines close by!!!!

Not enough neighbor's willing to sell out! :)

Anyway, small wind compared to huge commercial turbines is kinda like a RC model plane vs. a 747.

And yeah, lightning protection is essential!!!


~Martin

[Anon001]

Hi Paul,

First of all, i'm NOT "anti" going off grid... I just think that MOST times it's not what it's cracked up to be, and not as cheap as it seems either.

For instance, you are will willing to go without a LOT, to live off grid. You don't have an air cond option, you don't have a shop where you can build and fix your own tools. Perhaps you don't have a metal or woodworking hobby that requires a welder or table saw... When i want to weld, or use my impact with my compressor, it's there and it saves me a lot of money to fix things myself. If i'm too lazy to carry water from my ponds to my garden in pails, i have a electric pump and garden hose, that pumps water out of my pond for that purpose... If i want to power wash something, i use the same pump and source. If we have a hot muggy night, i can turn the air on for a while so i can sleep comfortable after working all day...

Most folks off grid buy a generator, and then run it to power the washing machine, or maybe to fill a water tank... That gen set and gas is part of the cost of electricity... So is the time it takes to do the maintance on those batts and cleaning those cables. As is the room most build to put those batts in... Some use 100 pound propane bottles, then haul them in to be filled. (you even have propane tank rent) That cost of driveing to town, adds to the cost of being off grid, and then there's the extra cost of that expensive fridge and freezer and ect. and ect.. (used fridges and freezers here are almost free) There are LOT'S of hidden cost to being off grid, and even though most folks don't mind them, they are still there and they still cost someone money and time...

Folks say "You're lucky" to me about a lot of things... I don't consider it luck, i could have bought property where electricity is expensive just like you did. I could have bought property with no tree's that i could harvest the logs out of to build with, and heat my house with. I could have bought a place with water problems ect... But i didn't, and that wasn't luck, it was buying the right place...

Anyway, if someone wants to be off grid, GREAT, just so they realize ALL of what it involves, and ALL of what they are giving up...

Anyway, great discussion, thanks for answering here...

DM

For starters, my comments were directed at the OP not you. I know you're not anti.... But, you and I both have seen people that start knocking alternative energy when when it's obvious they don't have any experience with it. One that comes to mind is someone that works for an electric utility that promotes the anti-alternative lifestyles using unfounded reasoning. Secondly, my lack of an a/c is by choice not situation in the same way that my lack of a furnace is by choice.

I've almost always used hand tools over power tools. About 90% of my house was built with hand tools. I could have used power tools because I've always had a generator.

Usually, alternative energy doesn't work, if the homeowner/family isn't conservative by nature or they expect the same luxuries that the neighbors expect them to have.

Like I've said before, I have everything I need and want.

Paul

[Bare]

Cap rate is the timely pay back of an investment. For example, if I invest $10K into a project and receive a $100/month in return, ......... let me get a calculator ................ that's $1200 a year, divided into $10K, comes out to 8.33 years. The cap rate in this case is 8.33 which wouldn't be that great but not that bad either. A cap rate of 5 or better is what I would have wanted for something like this. Anything above 10 is really a loser.

In my case, I had an option of these plastic panels which were durable but the glass panels were more productive (cap rate of 12-14). The catch is, the kids in the 'hood. I don't care where you go, they throw rocks and one rock would be disasterous.

PaulNKS, you make some valid points but when I evaluate a project I have to calculate my time as part of the formula. During the research and developement phase, I ignore my time and chaulk it up as a learning experience. Hence, the cost of education. Yet, my time is valuable even if it's goof-off time.

When it comes to these wind generators, simple is better. Instead of having a big prop style of fan, I think an AeroMotor type of fan would service much better and without the noise problem that annoys so many people every where.

The AeroMotor fan has produced power for Mid-Westerners for a hundred years or more. With today's tech, the problems of the past can be eliminated quite easily.

My electric bill is about $80/mo. NJ must have some outrageous rates. When it comes to power use, lights are small potatoes. The real power consumers are electric motors, burners and such. When one substitutes electric with propane to power a fridgy or freezer, one must include that in their power bill. It's all energy. It just comes down to how it is best accomplished.

I don't want to come off as some kind of amateur when it comes to off the grid living. There isn't anyone more off the grid than a remote gold miner. Back there, gasoline is a precious commodity. We used a gell cell battery for packing reasons. Lead-acid spills during transport to those locations and water for it, if needed would be contaminated at best. Cooking on wood became the prefered cooking fuel. An ax, a handsaw and a file to keep it sharp was all that was needed. Keeping in mind, all that is packed in must be packed out or used as fuel to cook with. And one must eat their mistakes. The dredge had the be the most fuel efficient and of the size necessary for the location. All-in-all, for the amount of work we did and the money we made based on the price of gold at the time, we didn't make that good of a living. I knew others who did a little better.

Looking back, a solar panel would not have produced the amount of power needed. First, most location were in a canyon. Sun came up around 10AM and lasted till about 4PM. It was light but there was no sun. Even if we chose, I don't think we could have packed in the size we needed.

I'm not opposed to organic power. I just wish there were better products available for the money spent. This is 2010 for crying out loud. One would think that this industry would be awash in innovation and technology. Right now, the most equitable power available is nuclear. Yikes! It is my opinion that if there were better products available at a better price, more and more people would have organic power. A builder here locally has offered solar electric built in to his homes for sale. People are buying it. I investigated it and they were awash in rhetoric and numbers but no bottom line. That was supposed to be impossible to calculate. PUULEESEE! Although I don't have numbers, I don't think they are doing all that well based on all that I've studied and learned. They just don't have that many panels up. The panels are integral part of the roof tiles. But more importantly is the participation of the buyers. They are willing to step up. I just think they got a snow job, that's all. There's a lot of it out there.

[12vman]

Firegirl1969..

I re-read your original post and I believe that your expectations with using a 250 watt array may be somewhat high. I'm not sure where the LittleChicken Ranch is but I'll try to show you how much energy to expect.. (In my area.. E. Central Ohio)

Figuring a 12 volt D.C. System.. http://www.altersystems.com/catalog/kyocera-kc125g-125-watt-solar-panel-p-1440.html

According to specs.. 2 panels connected in parallel.. Assuming bright, sunny day..

14.2 amps.. Max charge rate during perfect conditions..

4 hr./day (24 hr. period) Prime Charge Period.. 10 am 'till 2 pm..

56.8 aHr. collection a day. or, *681.6 Watt hours @ 12 volts D.C. (This is important!)

Rounding your collection to 60 aHr, 2-6 volt golf cart batteries connected in series would be plenty.

The part that will kill you is using an inverter for 120 v.a.c. items. An inverter demands 10 times the power from the battery @ 12 v.d.c. than what you want to operate from it. For every 120 watt load (1 amp @ 120 v.a.c.) requires 10 amps from your battery to the inverter to produce that 120 watts! (NOT including any losses) This in turn lowers the actual capacity of your battery by a factor of 10. (*68.16 watt hours) That's not enough energy to operate a 100 watt light bulb @ 120 v.a.c. for 1 hr.!

"Our future plans are for either a Hotpoint 16 cu. ft. energy star refrigerator with a daily rating of .88 kWh/day.."

That comes out to *880 watt hours/day, not including any of your other loads even if they are direct to the battery.

[patience]

I'm planning to use four 180 watt panels to run a fridge that uses (per my Kil-A-Watt meter) 840 watt hrs./day. Watts = volts x amps, so if all nunbers are in watts, it's kosher. So, my system will produce up to a max of 180 x 4 panels x about 4 hrs/day, or 2,880 watt hrs./day. More reasonably, I expect about half that after efficiency losses and less sun. That should leave me some for lights and a few other things. I'm using 8 Trojan T-105's with an MPPT ccharge controller.

[12vman]

Caution.. Don't just take the wattage rating of a panel to figure from it! The actual working current is different than you think..

Example.. http://www.altersystems.com/catalog/kyocera-kc125g-125-watt-solar-panel-p-1440.html

Check this out..

Using simple math with the above panel.. 125 divided by 12 = 10.41 amps.. Right?

Actually they deceive you with some fancy-dancy math using another voltage that's higher than the intended useage. (For longer charge time during the morning and the evening) If you look at the specs of the above panel, it only produces 7.10 amps! Multiply that by 12 and ya get.. 85.2 watts.. LOL

Actual current output from the panel is what you want to work with. Check yer specs!

[PowerGuy]

The posts in reponse to the original question regarding a 250 watt nominal array were excellent. We thought we would toss in some real performance data as part of the mix. We assumed, as did others, that the 250 watt array would be fixed, facing south, and seasonally adjusted for altitude.

Our critical loads consist of two deep freezers, one cooler and one standard kitchen refrigerator with automatic defrost (unfortunately). The total of these loads averages 5 kwh/day. We have twin single axis tracking arrays of 500 watts nominal each. The most we have ever seen in terms of output under ideal conditons of noon, cold and clear, is about 950 watts. That is power, not energy. The energy production over the long term, considering cloudy days, snow storms, etc., is 5.7 kwh/day in spring. The most we have seen in one day under ideal conditons, spring time day length, is 7 kwhs. This will likely increase somewhat as the summer season unfolds, since the full array has been on line since early March, but we don't expect it to go much over 10 kwh/day even with 18 hours of daylight per day. The tracking arrays allow production as low as 150 watts at dawn and dusk and our production at this time runs nearly 11 hours per day.

Our critical loads are similar to those noted in the original post. In our opinion, the 1000 watt nominal single axis tracking arrays (seasonally adjusted altitude), with a 14.4 kwh battery bank, are a minimum necessary to sustain our critical loads of 5 to 6 kwh/day over a long term grid down situation.

The potential disappointment, in terms of performance after spending a lot of money on PV panels and associated hardware, can be a shock, so we hope that you are thinking in terms of real rather than theoritical performance!

[firegirl969]

Ok, so I found an energy star fridge that is rated at 324 kWh per year. How many panels would I realistically need to operate this fridge? I already made a deal and ordered 8 Trojan t105 new batteries. (Ain't that a great deal, new guy in town trying to get business). So I should have the battery capability.

[PowerGuy]

Unfortunately, Energy Star ratings are not what they claim to be. Recently, a vacuum cleaner and a feather duster got an "Energy Star" rating. There is no review by qualified technical people within the government black hole. The only way to be sure is to check the T-Stat setting that produced the annual energy consumption claim, to make sure that it was reasonable. Afterall, setting the frig at 50F will produce a fantastic "Energy Star" rating. In comparison, we can give you the real ratings on our critical refrigeration units: Our two freezers are set at -10F to 15F for long term storage of meat, and each consumes 1.2 kwh/day (438 kwh/year). We have a 15 cu. ft. chest freezer operating as a cooler at 38F-40F that consumes only 0.25 kwh/day (91 kwh/year). If we were to go off grid, we would shut down our energy hungry kitchen refrigerator (840 kwh/year), with self defrost, and move all the food to our cooler. The cooler uses a much smaller amount of energy due to the fact that it was designed as a freezer with a much larger delta-T as a primary parameter. For you to adequately power a single 324 kwh/year load (~1 kwh/day), with a south facing and seasonally adjusted for altitude, MPPT fixed array, we would recommend a minimum of the 250 watt array that you originally mentioned. This assumes at least 5 hours per day of maximum input on average, which, depending on where you are, may not be realistic. Tracking would substancially increase performance, on the order of 40% in winter and 100% in summer, which is why, in our opinion, tracking hardware is more cost effective than additional panels to compensate for a fixed array orientatioin. To be on the safe side, and to power loads other than the one you mentioned, you may want to consider a minumum 500 watt array. In a practical sense, setting up a 250 watt array will be roughly the same cost as a 500 watt array in terms of structure and material. Ground mounts are, by the way, much superior to roof mounts if you can do it - maintenance, snow removal, etc. Your battery bank sounds good at this point, and is large enough to handle an array larger than 250 watts. Frankly, if you are sensitive to the cost of the panels, and can afford tracking, a 500 watt tracking array will produce roughly 3 kwh/day. This size array fits nicely on an old single axis satelite dish mount and is farily easy to install. We have found that more than 500 watts on a single mount creates wind load problems.

[firegirl969]

Thanks PowerGuy! We got a ground mount setup for FREE when the guy gave us the two 125 watt panels and the other solar items. I priced two 135 watt panels that replace the 125 watt panels for $430 each. I don't know if that is a good price, but I plan to do some more research. That would give me 520 watts total.

[patience]

A friend and I found the same thing with mountings. I ended up building a mount for his four 180 watt panels, on a 6" schedule 40 pipe post set in concrete. The panel mount could be tracked on both horizontal and vertical, but he is foregoing that until he can afford it. The panel mounting resembles an aircraft wing structure, with plasma cut 1/4" plates as vertical trusses, pivoted on a 2" schedule 40 pipe for vertical tilt. Four stringers of 1 1/2" X 11 ga. square tubing run the 10 ft. length of the mount and are welded to the plate trusses. The vertical axis pivot is a 2 ft. long member inside the 6" post, sealed from weather. The whole assembly is steel. For an informal test, we set it to horizontal position and he and I could hang on it with very little deflection (about 350 pounds) on one corner. The post is set in about half a yard of concrete, 4 feet deep. We are convinced that you could hit it with a truck and not seriously disturb it. Maybe it is overkill, but that is a lot of money hanging up there.

The mount I described is far stronger than the commercial aluminum mount another friend bought from Kyocera for 6 of their ~120 watt panels. His has been atop a guyed 6" pipe post for 2 years now with no problem, but 21 feet of 6" pipe was over $400 back then, to which I added guy points and a 1/2" plate welded on base for anchoring.

[firegirl969]

Patience,

Can you send a picture of that mount system for DH to look at? He thinks the one we got may be too lite. Thanks, firegirl

[PowerGuy]

FireGirl: How are you planning to string your panels together and what is your open circuit voltage? Do you have a MPPT charge controller lined up? We ran into this issue when we finally assembled our twin tracking arrays, since we had accumulated panels over a period of time due to costs. The manufacturer, in the mean time, had changed the spec's slightly so we had some 75 watt panels and some 85 watt panels. We mixed and matched so that we have two strings in series/parallel creating a 110 vdc open circuit voltage.

Patience: Way to go on the tracking array, and two axes to boot, very cool. We found that we needed two due to very high winds, and we mounted them narrowly on the frame to avoid creating "wings". Also, single axis tracking was tough enough in terms of electronics and mechanics. Two vs. one axis did not seem to make sufficient difference in performance to justify the extra effort. The difference between fixed vs. single axis tracker was, however, dramatic. We found an in expensive source for tracking sensors at:

http://www.redrok.com/led3xassm.htm

That LED sensor board, along with a simple linear actuator normally used on this dish mounts, was sufficient. Total cost for the mounts, sensors, and actuators was only $100 each. In this area, there are lots of abandoned satelite dish mounts rusting away in folks back yards. We used scrap steel and used unistrut plus our own welder for the frames.

[patience]

firegirl969,

Sorry, I am am IT idjit. Have never been able to TAKE a picture with my much-touted kodak digital camera, let alone figure out how to get it in the compooter and pooted out where somebody can see it. My daughter has done such things, but it takes a whole day. (You take 6 or 8 pix with it and the batteries are dead. Put in new batteries and then you have to reprogram it from scratch again--it goes brain dead without batteries. I hate that thing with a purple passion.) #%^%#%#!

Daughter hid the kodak camera, because she knew I would get my $160 worth out of it with a 20 ounce ball pein hammer! :D I have designed and built automated equipment to make monocrystalline silicon for semiconductors, but have no idea how consumer electronics operates.

NOTE: "Patience" is not what I HAVE, it is what I NEED!

That's okay. I know people who can take care of my needs. One of my customers owns the local internet provider and computer store. No problem. I fix his mechanical stuf, and he keeps my compooter working, despite my ignorance.

I built my own view camera, about 30 years ago, with full tilts and swings, (a 2 1/4" X 3 1/4" with a 120 rollfilm back on it) and had a darkroom to do chemical photography. Shot weddings and bird dog trials on weekends. The technology changed and I did not. :o

AFAIK, if it is a commercially made solar panel mount, it is not strong enough to suit me. YMMV. If I HAD to use a commercial mount, I would only use it in a fixed position, and guy wire the heck out of it. Those aluminum mounts won't rust, but they leave a lot to be desired, IMHO. I fix farm equipment for a living, and my SIL built log trailers for 15 years, so we tend to over design things. :p But our stuff doesn't break, either. (SIL's homemade windmill withstood hurricane IKE with no problem.)

If I can talk my DD into it, I'll get her to put up the picture.

[firegirl969]

We are one step closer. The tankless hot water heater came today, so we won't have to rely on electric hot water anymore.

[patience]

DD has one of those, and LOVES it! Uses very little LP, and no end to the hot water. They are off grid, so she uses a vintage Maytag wringer washing machine that we found in pristine condition. That runs on their solar system/inverter in summer when there is plenty of sun for power, or on a little 2 1/2 HP generator SIL built if the solar can't keep up in bad weather. And this is with only 2 solar panels, 180 watts each. The washer only has a 1/4 HP motor, 110 V., so it doesn't use a lot of power, which is why they chose that.

[firegirl969]

As I have mentioned in some of my posts, we have been cutting down our energy consumption over the past 2 months. It must be working as our power bill went from $260 two months ago, to $220 last month, to $137 this past month. With the new tankless hot water heater and eventually an energy star refrigerator or a propane one, we should have enough solar panels for just the lights and battery, computer, and cell phone charging, and 12-volt TV/DVD. We plan to keep the grid for as long as we can afford it, but it will be nice knowing we don't HAVE to rely on it anymore.

Patience, I am saving for a James Washer. I have read lots of great reviews on it.

[OTG Newbie]

Hey Guys, When I finally move I plan on being totally off the grid. I have been building my own solar panels for a while now & getting enough to power a nice size homestead (I also plan on using wind too). Currently I am just using roof mounted panels which is fine for here in So. Cal., but my plans are to be in Western PA, so besides just roof mounted panels I figure I will need at least 1 maybe 2 trackers. My question is, where would I find them, to buy? do they come in different sizes for different size panels? I have 4 panels that have 77 6'x6' solar cells on them (almost a full size piece of plywood each.). Since this array puts out a nice amount of power, I want to use it to the fullest that I can. Any info would be a great help.

[Anon001]

Many of your alternative energy distributors sell trackers. The one I use is BackwoodsSolar.com.

Paul

[PowerGuy]

We found an in expensive source for tracking sensors and controlers at:

http://www.redrok.com/led3xassm.htm

You can make your own...

PG

[firegirl969]

I have looked at that link on trackers and I am lost. DH and I are finalizing plans for our solar system to be in place in January. We are taking our 12 X 36 cabin and moving it back behind the pond on a very nice hill that is surrounded by timber. It is located in the back of the cow pasture so I will finally get to live my lifelong dream of being a hermit. My teenage kids will live in the SW with the new DGS, so I will only be a couple thousand yards from them, but I will finally have some privacy. DH and I plan to move it in January and put our 18 X 14 screened porch with the wood burning stove onto the front of the cabin. We close the porch in with plastic, so we can heat the entire cabin with the heat coming from the porch. We also plan to hook the propane on-demand hot water heater up and the solar power system we have on hand that consists of two 125 watt Kyocera panels. I still need input on the batteries as I was going to use large interstate forklift batteries, but several opinions have been that these deep-cycle batteries will not work well for this application. Therefore we are looking at trojan t-105's. We are going to add two kyocera 135 watt panels in February as we can afford them then. This will make a total of 520 watts. We will add a propane fridge as well. Most of our power will be for the tv/dvd player and charging the computer. We will use solar lanterns and solar motion detection security lights. DH plans to run a water line from the barn to our cabin and put a black nurse tank back there for a water supply with a 12 volt sureflo water pump with 2.8 gpm output. There is an old septic system back there so we will install a low water usage toilet into the existing bathroom. DH plans to have generator backup for the battery charging as well. We may have to use the generator for a/c usage next year if the summer is anything like this year.

As a side note, DH is thinking about hooking the cabin wiring up to the 3000/1500 watt inverter and hook this up to the battery bank for power instead of changing most wiring over to 12 volt as we don't plan on using 12 volt items. I know there will be some loss due to inverter usage, but is this significant or will his plan work ok? Thanks for all of the help, we are learning as we go, firegirl

[OTG Newbie]

I have agree, that link really didn't help, but it was the thought that was nice. Backwoods solar had a few, but really didn't tell me if they could handle the size panels that I had made. I guess I need to find someone who knows how to weld, and have one made.

Firegirl, do you just have the 3 panels or are you using wind too? how many watts/KW do you use in an average day?

I would love to see some photos of your place. It sounds like it is really coming together.

[PowerGuy]

https://www.impaktproducts.com/CBand-KuBand-Linear-Actuators-p-1-c-270.html

http://www.centralsatellite.com/

We are sorry that the sensor web site was not helpful. We have purchased 5 of these $35 sensor boards (3 spares...since they are really inexpensive), and used the pictures on the site give us ideas on how to construct single axis polar mounts from satellite components. Entire polar mount for a 500 watt narrow (wind resistant) tracking array cost us only $300.

The first link is the linear acuator for the polaf axis mount.

The second one is a source for a very robust polar mount, one that we have found to be sufficiently strong to deal with a narrow array in high winds.

And, yes, you need to buy some 10' sections of unistrut from Home Depo and do some welding! Also, digging, and concrete work as well.

If the two pics I uploaded appear, you should see how it all goes together.

PG

[firegirl969]

I have agree, that link really didn't help, but it was the thought that was nice. Backwoods solar had a few, but really didn't tell me if they could handle the size panels that I had made. I guess I need to find someone who knows how to weld, and have one made.

Firegirl, do you just have the 3 panels or are you using wind too? how many watts/KW do you use in an average day?

I would love to see some photos of your place. It sounds like it is really coming together.

Right now we have two 125 Kyocera and we are not off grid yet. I am looking at two Kyocera 135's to add to it. However, this morning I found Evergreen 205 watt panels for the same money as the 135's so we may go with those. The guy at backwoodsolar told me to wire each panel separately into the box, so I think I can go different brand panels. I plan to call this week on that question. I will learn how to upload pics of the property and get them on here as soon as I can. DH and I both want to get farther off the radar so we are really excited about the upcoming move. About the batteries, patience's DD uses a forklift battery with great success and that is what I planned to do as I can get them directly from the Interstate Battery wholesaler who is just 50 miles from us. That not only saves on the cost of the battery but eliminates shipping costs as well. I have gotten some feedback from some great friends on here that say those batteries aren't the kind I need. I can also get Trojan T105's for $95 each around here. I am not sure, but I think it would take alot of those if I am going to have 660 watts total in panels. So now I am more confused that I was to begin with.

[Anon001]

Firegirl,

You can mix brands and sizes of solar panels with no problems. The thing to remember is to wire them all for the same volt... i.e.. either 12 volt or 24 volt.

You would be better off going with everything DC as much as possible rather than AC. You will be surprised at how much less power DC will use, not to mention the loss through the inverter. Also, with lighting... if you have all AC and your inverter goes out at night, you will be without lights.

Check out the Interstate 6v golf cart batteries. I have 8 in my bank. I think you'll find that you can get more amp storage for the less money than with the Trojans. They will also last just as long as the Trojans. My last ones lasted from October 2002 through February 2009.

[12vman]

Three things that I consider in batteries. How easy are they to handle, amp hours per dollar, and how easy is it to find a replacement in a hurry.

Golf cart batteries fit the bill. I can handle them with ease, much easier than a Trojan, around 3/4 or more amp hour rating of a Trojan at around half the cost, and you can find them at Wallyworld or Sam's Club. Interstate sells a golf cart battery and a distributor can be found easier than a Trojan.

Trojans seem to last longer because they have a larger amp hour capacity. For the difference in money and the ease of moving and finding them, I'll stick to golf cart batteries..

Forklift batteries may be OK but ya gotta have a fork lift to move 'um! These old bones doesn't want to mess with that.. ;)

The tracker debate can go on for ever but I personally can't justify the complex mount and the chance of wind damage for the amount of true energy increase with a small system. It's easier and simpler just to add another panel. One panel could give you that extra that you might gain with a tracker and the mount is solid. You'll gain more with a tilt change during winter/summer, IMO. Striving for that few extra watts can be costly in the long run. Have you ever tried to carry a sheet of plywood in an open area on a windy day?

[12vman]

Firegirl,

You can mix brands and sizes of solar panels with no problems. The thing to remember is to wire them all for the same volt... i.e.. either 12 volt or 24 volt.

Also, you want to isolate each panel with a blocking diode. The smaller panels can become a load to the higher wattage panels.

[OTG Newbie]

https://www.impaktproducts.com/CBand-KuBand-Linear-Actuators-p-1-c-270.html

http://www.centralsatellite.com/

We are sorry that the sensor web site was not helpful. We have purchased 5 of these $35 sensor boards (3 spares...since they are really inexpensive), and used the pictures on the site give us ideas on how to construct single axis polar mounts from satellite components. Entire polar mount for a 500 watt narrow (wind resistant) tracking array cost us only $300.

The first link is the linear acuator for the polaf axis mount.

The second one is a source for a very robust polar mount, one that we have found to be sufficiently strong to deal with a narrow array in high winds.

And, yes, you need to buy some 10' sections of unistrut from Home Depo and do some welding! Also, digging, and concrete work as well.

If the two pics I uploaded appear, you should see how it all goes together.

PG

Thanks powerGuy! That Helps a lot more. :)

[OTG Newbie]

Three things that I consider in batteries. How easy are they to handle, amp hours per dollar, and how easy is it to find a replacement in a hurry.

Golf cart batteries fit the bill. I can handle them with ease, much easier than a Trojan, around 3/4 or more amp hour rating of a Trojan at around half the cost, and you can find them at Wallyworld or Sam's Club. Interstate sells a golf cart battery and a distributor can be found easier than a Trojan.

Trojans seem to last longer because they have a larger amp hour capacity. For the difference in money and the ease of moving and finding them, I'll stick to golf cart batteries..

Forklift batteries may be OK but ya gotta have a fork lift to move 'um! These old bones doesn't want to mess with that.. ;)

The tracker debate can go on for ever but I personally can't justify the complex mount and the chance of wind damage for the amount of true energy increase with a small system. It's easier and simpler just to add another panel. One panel could give you that extra that you might gain with a tracker and the mount is solid. You'll gain more with a tilt change during winter/summer, IMO. Striving for that few extra watts can be costly in the long run. Have you ever tried to carry a sheet of plywood in an open area on a windy day?

Thanks 12v. I may just stick with the roof mount for now. Adding another panel is a lot EZer. I build the panels as a hobby now & for friends wanting them. I have found building to not only being fun, but a lot cheaper than buying already made panels. :meeting:

[firegirl969]

Thanks Paulkns and 12Vman. Now I understand about the batteries. I just needed it explasined in plain english. Also, what are blocking diodes? Do I get them from backwoods solar or a similar place? 'preciate the help, firegirl

[12vman]

Thanks Paulkns and 12Vman. Now I understand about the batteries. I just needed it explasined in plain english. Also, what are blocking diodes? Do I get them from backwoods solar or a similar place? 'preciate the help, firegirl

Think of a blocking diode as a "check valve" in plumbing. A check valve will only allow water to flow through it in one direction. If pressure or flow is applied to it in the opposite direction, the check valve will stop the flow.

A blocking diode is a check valve for electricity. They will only allow current (power) to flow through them in one direction.

If you are using different sizes or types of panels in a system that will be connected together, it's important to install one on each panel either in the wiring leaving the panel or at the combiner box where they all get wired to a common point. This isolates the panels from each other so if one panel is either of a lower wattage or patially shaded, it doesn't become a load on the others. Power can exit each panel but none can flow back into a weaker panel if there's a problem.

To select a blocking diode, you need to consider the current output (amps) of the panel(s). Most blocking diode are usually rated at around 15-20 amps. Most single panels don't generate this much power so it's not an issue of a panel to ever overload it. I'm sure that Backwoods Solar or anywhere you decide to purchase them will lead you in the right direction. Just tell them the largest wattage panel that you have and the same diode will work on any panel that's smaller.