Need a little advice.

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Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Need a little advice.

    Hmm. Be suspicious of any site that tells you solar power is free. Unless they're willing to foot the bill for you to install the system, it ain't free.

    Running a K-A-W has two parts. One is where it registers the Watts the thing plugged in to it uses. The other is where it tallies those Watts up as the all-important Watt hours (kWh) when you leave it plugged in for a day or more.

    Otherwise you're not much further ahead than using one of those primitive 'calculation forms' offered all over the place where you put in Amps and Volts from the manufacturer's specs (nearly always inaccurate) and guestimate the usage time. Might as well spin a wheel and see what number comes up. :p
  • bill and rosa
    bill and rosa Solar Expert Posts: 26
    Re: Need a little advice.
    Hmm. Be suspicious of any site that tells you solar power is free. Unless they're willing to foot the bill for you to install the system, it ain't free.
    I know its not free I just use their tools. Believe you me. the 6k I set aside for this build is getting ate up fast. But I think for the investment its well worth it.

    Even if I have to buy 8 batteries every 8 to 10 years still cheaper than the electric company and all the taxes that get misused. (1400 to 2000 every 8 years is less than 20 dollars a month I need to save to replace them)
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Need a little advice.

    Argh! Those are the primitive calculation forms I was warning against! :p

    Look, you have the Kill-A-Watt meter? Let it run up some real Watt hour totals on everything you want to run off-grid. Total them up. Round the result up to the nearest half kilowatt. Accuracy counts. It counts in $.

    Now never mind about the 20 hour rate and trying to plan the power use for 20 hours. Use the 20 hour rate and expect it to supply ALL of the power for 24 hours. When you try to cut corners and trim things down to minimums you end up running out of power. The sun does not shine brightly every day, your load use will vary up and down, batteries lose capacity over time. Having more power available than you need is much better than having not enough.

    So you have a 24 hour kW hour number. That's in AC. Inverter conversion is usually around 90% (it varies with the particular model) so that goes up. Then the inverter's consumption is added in and you have DC Watt hours needed which the battery bank size is based on.

    You do not calculate array size first to supply the needs and then figure out how much battery you need to 'store' it. Why? Because batteries use energy to store energy. About 20% more has to go in for what you get out. So if you base the battery bank size on the power needed and then size the array to recharge that battery bank you come out ahead. This gets cross-checked with the array harvest potential (the Icarus formula with the 52% over-all efficiency ratio). So long as the panels can harvest more than you need it will be fine.

    Where you get in trouble is when you try to trim things to the minimum. Like rounding Watt hours down, leaving out conversion, forgetting inverter consumption, taking the batteries down to 50% daily, recharging at 5% peak current, and expecting every day to be perfectly sunny and six hours long.

    Believe me; people make those mistakes. Sometimes singly, sometimes in combination. The they come here and ask "why doesn't this work?" because they think they've done all the calculations right, often based on these on-line calculation forms.

    Heck I use short-cut rules-of-thumb all the time to get to the basic system design. But they have to be considered against the actual installation. Still, accurate 90% of the time. :D
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: Need a little advice.

    First things first...
    ...Even if I have to buy 8 batteries every 8 to 10 years still cheaper than the electric company....

    No, No it's NOT! I am as cheap as it can get and I can't be cheaper than "the grid" I've gotten it down to @26 cents a Kwh and where I live the grid costs for my usage is about 20 cents a Kwh. I know of no one else who has an off grid system that has shown they can get down as cheap as 50 cents a Kwh. I'd be surprised if your basic Trojan 105's would last 8-10 years though some people have had them last that long. It would be rare for a first set of batteries.

    If you want to "do solar" there are lots of good reasons, being cheaper is not one of them. If the power company is willing to do net metering, that would be the cheapest way to go, you would have the grid for AC and would not have all the waste involved in an off grid system. It might be cost effective if the "line fees" the electric company charges aren't too bad.

    Thioughts; your in an area where it is a dry heat (I think) so you might want to check out swamp coolers, which lower the temp by adding moisture to the air.

    If you decide to do solar in either way, if you have a system up and running before the end of 2016, there is a 30% tax credit...

    I always encourage insulation, when your electric costs more, it make insulation and conservation even more attractive.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Eric L
    Eric L Solar Expert Posts: 262 ✭✭
    Re: Need a little advice.
    the 1000 watts would be my daily normal usage, frig, lights, fan, tv. Everything else runs off gas (propane) This wattage is giving myself a extra 100 watts. I know thats tight but if I can achieve this then I know adding a couple batteries to my purchase would probably be good. Looking at the t105 450 but havent gotten a good price yet.

    Bill, as Cariboocoot said your saying this shows you don't understand what to measure. You're simply not in a position to be buying any equipment or planning a system until you get these basics down. Sorry to be blunt but it's your money we're trying to prevent you from wasting, as you likely already have with the equipment you've bought.

    If, like me, you're someone who learns by doing, I would recommend getting a small "hobby" system for now to learn how pv systems work. That's how many people started before trying to build a home system. I would guess that Northern Arizona Wind and Sun could help you build a very simple, very cheap pv learner system if you called and asked them to help.
  • bill and rosa
    bill and rosa Solar Expert Posts: 26
    Re: Need a little advice.
    Eric L wrote: »
    Bill, as Cariboocoot said your saying this shows you don't understand what to measure. You're simply not in a position to be buying any equipment or planning a system until you get these basics down.
    Thats why I have been on this forum to get help before I spend the $6000 dollars I have set aside for this new life. I dont mind your bluntness but I think you might should have read the entire need a little advice topic. Thanks for your input.
    Sorry to be blunt but it's your money we're trying to prevent you from wasting, as you likely already have with the equipment you've bought.

    If, like me, you're someone who learns by doing, I would recommend getting a small "hobby" system for now to learn how pv systems work. That's how many people started before trying to build a home system. I would guess that Northern Arizona Wind and Sun could help you build a very simple, very cheap pv learner system if you called and asked them to help.

    I have only spent 200 dollars on a small grid tie / battery backed system to learn with. Have had it in service for one year. I built the panels myself did the whole system myself. This system is on my kids house in georgia. I lowered my light bill by 65% and the have lights and a fridge during power outages. I have my hobby system.
  • bill and rosa
    bill and rosa Solar Expert Posts: 26
    Re: Need a little advice.
    Photowhit wrote: »
    First things first...
    If you want to "do solar" there are lots of good reasons, being cheaper is not one of them. If the power company is willing to do net metering, that would be the cheapest way to go, you would have the grid for AC and would not have all the waste involved in an off grid system. It might be cost effective if the "line fees" the electric company charges aren't too bad.

    My latest quote from the CVEC to bring power into my property just went up since my cabin is considered to small to be a real home. 480 sq ft main floor 288 sq ft loft. My quote today was $7400 to run power to my cabin (home). They will not give me the first 300 ft free.
    So realistically a $6000 solar/wind system isnt bad. I am not basing any of my gathered power from my wind turbine just solar. The wind will be my helper and will install later. Cariboocoot suggested this to me and I have taken it to heart.
    Thioughts; your in an area where it is a dry heat (I think) so you might want to check out swamp coolers, which lower the temp by adding moisture to the air.
    thanks I will look into them. Seen one in Northern California but didnt research deeper. Even looked at the way I cooled the barn for the pigs by setting up a drip line down the center of my roof and running water on very hot days. collect the water for re use.. But its just on my scratch pad as an idea for now.
  • bill and rosa
    bill and rosa Solar Expert Posts: 26
    Re: Need a little advice.

    I will for a while not post in the forum. I will just read. Cariboocoot if its alright with you I will send you a message with any of my questions. You have been giving me SOUND good advice through out this topic. Many others have helped and I am grateful. Any one else who wants to give me sound advice can message me. Thanks again for the forum and the help. Back to the reading and drawing board to re think everything. Thought I was getting close to a startup system with expandability. (bow)'s to all the knowledgable people here in this forum.

    Bill
  • Eric L
    Eric L Solar Expert Posts: 262 ✭✭
    Re: Need a little advice.
    I have only spent 200 dollars on a small grid tie / battery backed system to learn with. Have had it in service for one year. I built the panels myself did the whole system myself.

    Bill, I may have had you confused with someone else on the forum then -- sorry if so.
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: Need a little advice.
    ...So realistically a $6000 solar/wind system isnt bad. I am not basing any of my gathered power from my wind turbine just solar...

    I think most of those here do not believe you will be able to build a $6000 system that will meet your needs. As others have pointed out you may not understand your needs yet.
    ...From the electrical side the fridge and freezer will be the biggest draw of wattage roughly 400 watts.

    A refridgerator will run 1Kwh or more per day. A Freezer another 700 Wh for small newer chest freezer. Most likely any addition above about 1Kwh a day and most likely you'll want to run a higher voltage system. I can only imaging you read that these draw 400watts at a single point in time, but over time "Watt hours" is what you need to look at.
    ...The lighting will all be 12 volt (45 watts)...

    Most of us have given up on running 12 volt for lighting. You may give up for practical reasons, like needing/wanting to run a higher voltage battery bank/solar array. But worry about voltage drop in low voltage wire runs. The reason for running hiogher voltage array and battery banks has to do with equipment based on current, a charge controller that can handle a 1000 watt array at 12 volts will handle a 4000 watt array at 48 volts, over the same thickness wires.

    Get a real handle on your energy needs and you may find you need a larger array/ battery bank. If you can do a grid tied system you will not have the battery need, and to offset your electrical needs you will need roughly 1/4 the array. Yes off grid is typically that wasteful! (feel free to ask 'Coot!) perhaps a grid tied system is looking better now? Well you don't need the inverter either.

    If your going to figure your costs over 30 years (and I hope you live many more!) Figure on replacing batteries every 3-5 years for standard golf cart batteries, 5-7 years for L16 batteries 10-15 years for large single cell batteries, 15 years for forklift/traction batteries. Figure replacing your electronics every 10 year, charge controller and inverter.

    Here's a thread about Al who is setting up a cabin in Texas. I think he started 12 volt and small array and was up to a 24v and 1200 watt array when we last heard from him. He wanted a fridge and some AC.

    Here's a thread about my system optimized for summer A/C use with a realistic cost analysist. Doubt you can get the system I will have for under 14K with out hunting very hard!

    I'm not a fan Missouri Wind and Solar, I was thinking I would just get off cheap and buy what I think is the same Charge controller you are looking at, I asked about the stages and they said it was charging or not, and didn't make any attempt to understand stages of charging or what stages it had... Don't think I would buy anything from them.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • bill and rosa
    bill and rosa Solar Expert Posts: 26
    Re: Need a little advice.

    Thank all of you for your help and input. I know most of you dont think I have a clue. Its probably I dont know your terminology. I expect that. But With your input and the other input I have gotten from Professional system designers I have got my rough system design on paper. Once I get it installed in the spring I will come back and give you all the full information. Again Thank you all. Especially Cariboocoot, your honesty and understanding was the best help. Thanks for understanding that I dont know all the right words to use with my question.

    Respectfully,

    Bill
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Need a little advice.

    You might post the details of your proposed system for those here to critique. Hard as it may be sometimes, most of the folks he are very smart, and very experienced with PV systems, so a quick suggestion or change here or there, even on a "professionally" designed system might save some agony futher down the line.

    Good luck and keep in touch,

    Tony
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: Need a little advice.

    I hope you got a chance to follow the links in my last post, Al is doing a very similar thing.

    Getting use to living off grid might be easiest, if you start by camping out with out electric, then as you grow into your system each addition becomes an enhancment to your life. I lived for 5 years on a tiny solar array in Missouri with out air conditioning, it sure can be done, hope next summer is nothing like the last! Certainly much of the world lives with much less then we have become use to in the United States.

    Wish you the best of luck! I'll book mark your site and check things out as you go along!
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • bill and rosa
    bill and rosa Solar Expert Posts: 26
    Re: Need a little advice.
    Photowhit wrote: »
    I hope you got a chance to follow the links in my last post, Al is doing a very similar thing.

    Getting use to living off grid might be easiest, if you start by camping out with out electric, then as you grow into your system each addition becomes an enhancment to your life. I lived for 5 years on a tiny solar array in Missouri with out air conditioning, it sure can be done, hope next summer is nothing like the last! Certainly much of the world lives with much less then we have become use to in the United States.

    Wish you the best of luck! I'll book mark your site and check things out as you go along!

    Thanks for the advice.

    As we are over the road truck drivers and I am retired Military. We live in a semi truck off 4 batteries and a pure sine 2500 watt inverter and a small generator to charge our batteries when we are not driving. We run a small fridge/freezer and microwave and a MAC and tablet and a few other cooking appliances. We have gotten very efficient at living out of a truck. We are on the road 330 days a year at this time in our lives. We carry a small 4 person tent to use when we are waiting on a load in area's where we can use it. Mainly out west they allow free camping in desert area's. We hardly run Air conditioning due to fuel milage. We have modified our semi to get beter fuel milage with low rolling resistant tires, air tabs, gearing etc... So we are very diligent in saving money and researching prior to spending our money.

    We camped out 2 days on our land and after DEC 4th we will have our building to start staying in and completing. We have not bought the first appliance but have researched them for electrical usage by energy star. We KNOW to buy according to the size system we are building. We are buying the MOST efficient items we can. Also have contacted the maker of several items to try and get better information.

    So we might seem not to know anything to the group, but we just dont know some of the terminology that has been used. But when it has been explained to use then we have a good understanding. PLUS we use 3 consultants from different companies to insure we understand. Also using 3 companies to get 3 opinions to base our decisions on. Which I think is a very smart thing to do. We also have used the information gathered in this forum to raise questions and used this information here to verify with other professionals that what we are being told is good or bad information.
    Respect to all of you for your help and understanding. RESEARCH will always prevale and keep you from wasting your money. Always select several items to use to get peoples reaction to them. Cant always trust the reviews on the products website. Use forums, groups, social networks and professional advice to help you get the right items.

    Good luck to all of you and thank you again.
    Bill