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solar panel

Discussion in 'Renewable Energy' started by waj1d5, Feb 12, 2012.

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  1. waj1d5

    waj1d5 New Member

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    Hi to all of u just saw this forum and i thought to join it. I have a big project in mind and i`m a beginner in this issue and wanted to ask for help.

    This summer i thought that would b a great investment to put solar panels, and save money.

    I want to install solar panels in my house because of the low shading and there is no problem with the sunlight approximately the daily day time light is 13 hours and in summer is 15 hours.


    I dont what I have to know and more or less I know what i need.
    This is my first thread please could u post me with no very technical words and u do explain it
    Many thanks and sorry to be rude. :confused:
     
  2. cr0sh

    cr0sh Member

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    I am not an expert on this subject at all (and there are people here who are, so listen to them more than me) - but I will throw my thoughts into this mix:

    First off - what are you doing this for? Is it to save money, energy, both? Mostly likely it is - so have you already done everything else possible to your house in preparation for this? Things like extra insulation, better windows (double or even triple pane), efficient heating/cooling systems, attic ventilation (where necessary), planting of shade trees or other passing shading measures. Have you changed out your lighting system for things like CFLs and/or LEDs (where possible and/or desireable)? What about weatherstripping and caulking for leaks? There are many more things you can also do/look into - all of these measures (and more - one of the hardest ones to change is your daily energy usage habits, but its also one of the ones that will save you the most!) will save you money, and should be put into place/practice long before you get a solar panel system put into place.

    Once you have done so, then I say as a beginner, seek professional help: Look for and hire a contractor who has experience (or better, specializes) in residential solar installation. This will have many advantages, not the least of which is you will get a system which will work and not burn your house down or cause other problems for you as a homeowner (like being up to code, etc). He'll also be able to determine (or hire a civil engineer to determine) if your roof or wherever you plan to place the panels can support the load/weight.

    You also want to think about whether you want a grid-tie system or not; grid-tie ties the system into the grid - you run off the panels mostly, but the grid acts as your "battery backup" (mainly at night or on cloudy days). In this case, you still pay money to the electric utility company, but less than you would without the solar panels. Non grid-tie systems use a battery bank (which is something you would need to maintain and service, not to mention have a place for storage of the bank). Both systems use inverters to convert the DC voltage from the panels to AC for the house. You might also want to think about a solar water heating system to go along with the electric providing panels (depending of course on how your water is currently heated - alternatively, you might look into tankless heating solutions as well).

    Another thing to think about is your roof: When did you last have it replaced? If its been a while, or you don't know they age of the roof, or you can't remember - then consider getting it replaced -before- you install the solar panels, mainly because if you find you have to have the roof replaced later, you'll have to hire a contractor or other service to remove the panels prior to the roofing being done, and having them re-installed after the roofing is completed - which will only add to the cost and inconvenience (and if the installation isn't a grid-tie system, that inconvenience might be large). When you get your new roof, go for one that won't need replacing for 30-50 years, depending on your age (make the roof-replacement issue something for the next homeowner to worry about).
     
    • Thanks Thanks x 1
  3. waj1d5

    waj1d5 New Member

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    Many thanks for the reply, I already thought about all those issues. I want this project done in south asia, where i come from.I am doing this for necesity.You know in Pakistan the low shading is about 12 or 13 hours or more daily in summer and 10 or 11 hours in winter, and I thought that those 12 or 11 hours remaining I would fill them with solar panels.

    I want this energy source because its FREE, more reliable and easy to get because as i said before the daily light time is about 11 and 15 hours and for this reason I want this energy source.

    I know that they r plenty of professional help in pakistan but I want to do it for myself. IF U WANT TO DO SOMETHING GOOD DO IT YOURSELF. Just Imagine I call a professional to install me the full system and just after a week later the system stops or breaks then I have to call the technician and again and I just checked that installing all of that will cost me about 2000$.If I do (actually living in UK) I know the health and safety rules I know electrician I will buy the full system install it and according to my calculations will cost no more than 1000 english pound.I will save a huge amount of 1000$ and a full sack of knowledge.

    In south asia the roofs r open , means that their not like in europe or america, with no roof.XD.They r like big, massive open balconies.I will try to attach a picture if i can.The roof it is not a problem.( The house with pink paint roof that is mine)Ah the house is about 4 or 5 years old and we live in a small beautiful village, if u want to know the name ask me I will be happy to answer u.XD
    View attachment 61116

    The most of the time we use the electricity for basic needs like bulbs lights/tubes, fan...At the moment will be for basic needs.

    Always happy to learn a new thing everyday.
     
  4. dave

    Dave New Member

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  5. waj1d5

    waj1d5 New Member

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    I have thought 2 of these
    http://www.ebay.co.uk/itm/240W-Mono...=UK_Gadgets&hash=item256ccb63e0#ht_5866wt_952
    to getting start
    http://www.ebay.co.uk/itm/250W-Sola...SetTopBoxes&hash=item43a9cf47a2#ht_2006wt_952 for the inverter later i will look for the battery charge controller.:p
     
  6. cr0sh

    cr0sh Member

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    To be honest, the ebay advert for that panel appears a bit sketchy to me; not a word on model # (so you can look up specs), or the real specs themselves (voltage & amperage), so you're left guessing. That's assuming they won't just take the money and run (use an escrow service).

    Will 250 watts be enough? I think you'd be lucky to run a TV and a light or two off that, but if that's all you're going for - then ok. Personally, I would look for something larger (and something with screw terminals or similar for both input and output - not just binding posts) - maybe in the kilowatt range. If you are planning on running a house off this (even just a few rooms), you're probably going to want it near wherever your breaker or fuse box is (along with the batteries and lead-in from the panels), and you'll want to be able to mount it near the box, and tap directly into the home circuits.

    You posted a picture of your house - but I wasn't sure if it was the foreground building (with the flat roof), or the background house (that seemed to have a pink roof); does the house have utility supplied electricity, or nothing (or generator) right now? I'm just asking because if you intend to keep any utility, you'll need a way to switch between the batteries/solar and the utility (unless this is a parallel install of some sort to augment existing system(s)).

    If this is for "basic needs", then 250 watts from the inverter will be real basic (you won't get the full 250 watts, btw - maybe closer to 200); but if that is all that is needed - then it should be OK. But I'd be wary on that auction of panels - something doesn't look right to me there...
     
  7. mr.s.p

    mr.s.p New Member

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    I have a very similar arrangement.

    The panel is a Sharp 245 watt Poly and the inverter is a 350 watt Chinese modular GTI that plugs in to an existing power socket.
    There is nothing complicated about it, no running cables back to the main fusebox, simply plug and play.

    The downside to this type of installation is its reliance on the mains supply. When the sun shines, the power from the panel feeds the inverter, and if there is a mains supply, the inverter supplements the mains with this power. Unfortunately, if there is no mains supply, the inverter sits idle and cannot supply any power to the house.

    My mains power is very good compared to some places, so the lack of mains doesn't affect me but it could be a problem for people with a less than stable supply. This is unsuitable for people with no supply at all.
     
  8. waj1d5

    waj1d5 New Member

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    Yeah I know that 250w or 400w its a bit basic but at the moment that I can afford , if everything is going well I would like to go for the kw.I know that 250 or 400w i will run couple of bulbs/tubes and fans but the tv can wait XD .I have though for sure these
    http://www.ebay.co.uk/itm/2-x-Solar...UK_Gadgets&hash=item3cc13840e3#ht_1390wt_1185
    probably this one.

    My project is put the solar panel on the highest point of the house then put the inverter ,after that plug in with the batteries and then switch it with the house View attachment 61243
    .Right now we use the electricity but with a lot of low shading, I already use a generator but there is no point using it ,is noisy then the fuel prices...
    I used to plug the generator to the house so we do have the two way switch.
    I have thought that we could use the battery at night while in the day their recharge or use the solar panel during the day and the electricity recharge the batteries, not sure about the last one or use one panel for the batteries and the other one we use it during the day :(. Any suggestions?
    I am not sure about what inverter and how ( what characteristics) to choose?:confused:
    And what about batteries how do u know it is a good battery ,how long will last the power?
     
    Last edited: Feb 19, 2012
  9. 4pyros

    4pyros Well-Known Member Most Helpful Member

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    You need to deside on what voltage to run your system at.
    How many panels and volts can you get out of them.
    The battery votage should match that as well as the inverter input voltage.
    It all comes hand in hand so you need to think about the hole system then pack parts to match.
     
  10. nsaspook

    nsaspook Well-Known Member

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    Be sure to spend your money of a good inverter (pure sine wave) . The Xantrex prowatt sw series are inexpensive and have a low idle current with good surge capacity.

    Get a good set of batteries. Don't waste money on automotive types. A set of 6V GC2 type golf cart batteries wired in series will last a long time even with heavy abuse.

    Don't skip on fuses. A primary battery fuse is a must for fire safety.

    A good solid PWM charge controller like the Xantrex C40 should handle a small off grid system of less than 500W of PV. If you plan using a high power PV array later (1000Ws or more) a MPPT model might be a good investment even on a small starter system.

    Things that are nice to have:

    A battery monitor that can keep track of voltage and power (Ah) usage from the battery and what's been put back from the charger.
    A SG meter for checking the condition of the batteries if you use flooded cells.
    A battery disconnect switch to allow you to use a external charger on the battery when there is no sun for a few days.
    A good three stage AC utility charger of at least 20 amps.


    When all losses are accounted for you will only get about 60% of the power you put in back as power later so size your AC power loads realistically.
     
    Last edited: Feb 19, 2012
  11. mr.s.p

    mr.s.p New Member

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    The panels are fine but the inverter is the wrong one for your project.

    The panels and inverter will work as long as you have mains supply, as soon as the mains supply fails, the inverter goes offline.

    There are no batteries required either.

    If you want to use batteries, you need a different type of inverter and a solar charge controller.
     
  12. nicole.b

    nicole.b New Member

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    Solar panels can really be a good investment for Pakistan. As an Asian country, you can be assured that there is sufficient heat coming from the sun to support a household's energy consumption. One of the considerations that you must have is the position of your solar panel. It must be placed in a location where the sun directly shines. No matter how sunny it is on your location, if it doesn't shine on your solar panel, it wouldn't work. You may want to install your solar panel by yourself or you may want to hire a contractor to do the job. If budget is not really that much of a concern, you can go for a contractor so that you won't have to worry about positioning and and the connections. :) N.B.
     
    Last edited: Mar 26, 2013
  13. bryan1

    bryan1 Well-Known Member

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    As far as using a contractor to screw a few screws in into the roof to mount the panel it is very doubtful they will even bother to check for the best angle for the best position and charge an arm and a leg for doing the job.

    Now an easy way to check for the best angle get say a 8" square bit of wood board and lightly hammer a 6" nail in the middle. One will need an angle gauge to attach say underneath the board or where it can be easily seen. Then just point the board towards the sun until there is NO shadow of the nail and read the angle gauge. That angle will be the true position for the PV panel for that time of year, so it is best to do this test 4 times --- spring,summer,autumn and winter.

    Depending on the wind loading one can have a swivel mount with 4 preset points (one for each season) and that would give one better output all year round but not the best output. In order to get the best output the PV panels should go onto a tracker so the PV panel is in the best spot for max current throughout the day. One can use LED sensing circuits ( which can hunt when clouds come over) or simply go with a timed array (moving X amount per hour).

    A MPPT can also be used to get the absolute most power out of a solar panel and the panels are usually put in series for a higher voltage input then the MPPT outputs a higher current at the battery voltage.

    Now for sizing panels for a battery array, going 12 volt will mean extra heayduty cable for the high currents needed. 24 volt is better as the current is halved and is generally used by small to medium systems. 48 volt is by far the best way but also the most expensive.

    Ok say we have a 24 volt 250AH battery array and we want a PV system to charge it. Charging goes on what is called a 'C' scheme where say if one put 250 amps into charging this would be C1 and would soon cook the batteries if left unattended. The more common is C10 where 25 amps is needed or even down as far as C20 where 12.5 amps is needed.

    Either way one looks at it one or 2 panels isn't enough and when working out how many panels are needed for a standalone system a decent safety margin HAS to be put into the equation. With passive mounted PV panels mounted on the roof of a dwelling they will only reach top output for a short time each day when the sun is directly over head, the time of year is right for the roof angle and there are clear skies.

    Ok to get mains power out of a battery array one needs an inverter and forget mod sinewave ones as they do destroy consumer good's, won't work on some and worst of all have a huge standby current.

    A pure Sinewave inverter is the best way to go and one has a real low standby current say no more than 10 watts so the battery array isn't heavily drained when nothing is turned on.

    I hope this gives the OP a bit of an insight to the question asked.

    Regards Bryan
     
  14. Bach On

    Bach On New Member

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    I sense that you want it now. But planning a solar system for the long-term is an expensive project. You seem to want to start small, then grow the system as the money becomes available.

    People here have already expressed doubts about the size of your solar panels. You've identified that you have good sunlight. But that's only part of the umptyeleven-hundred things you have to consider to have a practical system.

    I know you don't want to hear this, but you did ask for advice. I wonder if it would be better for you to take the money you have now and put it in an interest bearing savings account? Then keep adding to it until you have enough money to build your system as it should be. During that time, continue to research your needs. The cost of panels and inverters has come down in recent years. Going for a 12 volt system is going to call for more expensive wire because of the current and voltage losses over the length of the wire.

    I don't sense you are ready to do this in a big way - i.e.,financially or with practical knowledge. And doing it in bits and pieces will cost you more in the long run. It will be fun to learn, but it will cost you more in the long-run. Do you want a practical system or just a hobby to dabble with solar panels and batteries and a few lights? Lights are probably the smallest portion of your electric bill. The big gulpers of electricity require lots of amps. And that means a much larger system. YOU WILL NOT SAVE MONEY WITH A SMALL SYSTEM.

    Like you, I want a solar system to bring down costs. I've begun to see that batteries are often the weak link in many systems. Scrimping there will end up costing you more over the life of your system. And this will greatly reduce any savings a solar system could give you.

    Attend some seminars and join a local group that dabbles in this. Don't just buy the first things that fall within your budget now. If it is important to you, you'll continue to add to your savings account and be able to buy a system that will last for the long-haul. And you will increase your knowledge so you buy more wisely.

    Good luck!
    Bach On
     
  15. audioguru

    audioguru Well-Known Member Most Helpful Member

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    What is "shading"? Is it when the electrical utility company turns off the power for an area because they do not have enough capacity? Then why don't they expand their capacity like everywhere else?
     
  16. Mr RB

    Mr RB Well-Known Member

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    Hi A.G, he said he has "low shading and no problem with the sunlight".

    I believe that means his roof is not shaded by trees, so it is a good place for solar panels where they get full sun.
     
  17. audioguru

    audioguru Well-Known Member Most Helpful Member

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    In Canada, electricity is inexpensive and reliable. Maybe it is the opposite in Pakistan and I do not know why.
    Private solar power projects in Canada are expensive so the government pays a portion so that maybe they will not need to build another very expensive nuclear generating station.

    In many isolated locations, electricity is made by windmills, not with solar panels.
     
  18. Bach On

    Bach On New Member

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    Some areas have better wind patterns than others. Never been to Pakistan, so I can't comment on that. There's a group of families in the mountains of Colorado that use windmills to provide a lot of their power. Their website is www.otherpower.com They have some good information for building windmills.

    Bach On
     
  19. ethelknox

    ethelknox New Member

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    If you're planning to go green on your boat, solar panels to charge your deep-cycle battery probably occupy a place on your "to do list." Sizing the solar panel for your boat's needs requires that you calculate the wattage that the solar panel must produce to gently charge the battery--a trickle charge. This means knowing the sources of electricity on your boat and how much electricity is used for each appliance or device.
     
  20. Bach On

    Bach On New Member

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    Thanks for the input. But my question about my flooded boat batteries was in another thread. I don't want to distract from the questions raised by the man from Pakistan.

    BO
     
  21. Norator

    Norator New Member

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    Ms. Knox, I hope that is not your home address. With Factor Analysis and other even more sophisticated statistical tools the denizens of the Internet can know you better than you know yourself.
     

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