Completely Green - Need Help with Basic Setup and Supplies

Hi All,

I'm a complete newbie/green in solar power and wanted to perhaps get a very basic summary of what I would need to get started.

I'd like to go off-grid power with regards to a get away home I intend to build in the next few months. It will likely be between 1600 to 2400 sq feet, plans are in the works now.

What are the basic components of a complete solar powered system, and what sorts of power can I expect to generate in terms of specifics that I can run off a system?

What would I need (panels, battery, wiring, etc) to power basic lighting, some appliances, and/or washing machine, computer/tv/etc?

How feasible is it for someone who knows very little (me) about energy and installations in general to put something together like this?

Are there plug and play systems available, and are they generally overrpiced?


Thank you for your patience and assistance.


George

Comments

  • tallgirltallgirl Solar Expert Posts: 413 ✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies

    The first thing you need is an estimate of your power requirements, as well as information from local builders about "green building" and "zero energy homes". Try Google for builders local to you.

    Square footage is not an accurate indication of power requirements. There are people who can live with very little electric power in large homes, and some who can't seem to get by without wasting power in small homes. You need to decide which one you are, and then make sure your new home is going to be built that way.

    As for can someone with no experience install a solar power system -- my experience is that even people with experience have problems. Go with a reputable professional in your area. Solar is a long term investment and not something scrimp on. Done well it can last for years on end. Done poorly it will cause nothing but trouble at the least opportune moment.
  • icarusicarus Solar Expert Posts: 5,153 ✭✭✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies

    What Tall girl says, with a few additions.

    You must first calc your loads, remembering that everything you do to reduce loads will make a system that is that much cheaper to buy and maintain. Second, loads WILL grow with time. The best thing you can do is spend a lot of time reading (here and elsewhere) about PV solar/energy conservation etc. By doing this home work before you buy ANYTHING you will potentially avoid the most expensive pit fall of Pv,,, The READY, FIRE, AIM syndrome.

    Also you have to take a hard look at your usage patterns now and into the foreseeable future. Many answers change as you rephrase the questions. For example, are you going off grid because you think it is going to be cheaper? (Not likely!) Are you going to use this cabin 2 weeks a year? Week ends, full time? Each of those answers is likely to produce a different right answer to some questions. For example, the choice between a Propane fridge and a conventional fridge hinges largely on how many days per year you are likely to use it. The more days, the more advantage to the conventional, fewer days, the advantage goes to propane.

    Another consideration is what are you going to use for back up power? You may find that buying an efficient gas or diesel generator is net/net way cheaper than off grid Pv if you are only going to use it occasionally. For example, in my little house, I use ~.6kwh/day. Or solar system came into being because of the desire not to have to listen to a generator at night. That said, with the advent of the small inverter serise gennies (Honda eu for example) I can hardly hear one run. We could run the house with a honda Eu 1000, burning ~ 1/4 gallon of fuel a day costing ~$1/day, way cheaper than we bought and installed the solar.


    The solar provides other benefits (24/7 power for example) but it comes at some considerable cost. The sort of rule of thumb is that battery based PV cost ~twice as much as grid tie, and delivers ~ 1/2 as much power net/net, resulting in 4 times the cost. A typical grid tie system might run $5-8 watt nowdays, so battery might be closer to $10. Of that ~1/3 of the cost is batteries that have a (very) finite life. Depending on service, type etc you have to count on replacing batteries ~5-10 years.

    My batteries were ~ $500 and will last ~5 years let's say. (Little battery bank 450 ah) That $100 per year just for batteries. Most battery systems are 2-5 times as big as mine.


    So the reality, is, yes, you can DYI, but you must learn a fair bit about what you are doing. Yes, you can build a off grid system. No it won't be "cheap" especially if you bring to your cabin the habits of town. (Simple example, a 1500 toaster, used 12 minutes a day = 300 wh. That is ~ 1/2 of our TOTAL electrical consumption for the entire day. Microwave, 12 minutes, the other half! The point is, it all adds up pretty quickly.

    Finally, as you do the math keep this in mind. If you take the name plate rating of any PV panel, divide it in half, (to account for all the system loses between the PV and the load) and then multiply that number by the hours of "good" sun you can expect on average (seldom more than ~4) So a 1000 watt system might look like this. 1000/2=500*4=2000 wh/day available. (the real number is closer to .53 not .5 but it is easier to do in ones head!)

    2kwh is a pretty small number for most folks. Two other things to keep in mind going forward. First, people tend to under estimate their loads, and they at the same time over estimate the amount of good sun they get, leading to a system way too small.

    I susggest that you do a Pvwatts test for your location: http://rredc.nrel.gov/solar/codes_algs/PVWATTS/version2/

    Good luck, and welcome to the forum. Feel free to ask as many questions as you wish, there are some folks here who have forgotten more about PV than most of us will know!

    Tony
  • PhotowhitPhotowhit Solar Expert Posts: 4,956 ✭✭✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies

    What Tall Girl and Icarus said with a couple more points.

    Federal tax credit is(or at least was) for primary residence only.

    Off grid typically is NOT GREEN!

    More energy is used in creating the solar panels and recycle the batteries than energy they creat that will be used. Most often grid connected systems are Green in that they 'payback' the energy used in creating the system in a few years. This has to do with the wasted energy once batteries are fully charged and the recycling of the batteries (on top of the panels and balance of system)
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • icarusicarus Solar Expert Posts: 5,153 ✭✭✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies
    Photowhit wrote: »
    What Tall Girl and Icarus said with a couple more points.

    Federal tax credit is(or at least was) for primary residence only.

    Off grid typically is NOT GREEN!

    More energy is used in creating the solar panels and recycle the batteries than energy they creat that will be used. Most often grid connected systems are Green in that they 'payback' the energy used in creating the system in a few years. This has to do with the wasted energy once batteries are fully charged and the recycling of the batteries (on top of the panels and balance of system)


    Not to get into a P*&***g contest, but do you have any documentation for that statement? My hunch ( and it is only that) that that is a urban myth. If batteries are recycled what does it really cost (energy wise) to build batteries? (and PV).

    Tony
  • BB.BB. Super Moderators, Administrators Posts: 29,332 admin
    Re: Completely Green - Need Help with Basic Setup and Supplies

    The conservation of somebody doing off-grid at 0.6 kWhrs per day (like Tony) vs somebody doing on-grid at 60 kWhrs per day (somebody with A/C and a home in the American Southwest)-- That, to me, is the difference in doing the "green" thing.

    An off-grid system that is capable of supplying a 60 kWH per day load is got a lot of hardware costs (panels, wiring, electronics, batteries, and possibly even a genset+fuel for backup) is hard to say that is a "green" installation.

    There are probably "cleaner" utility generation stations and "dirtier" generating stations.

    To compare a natural gas fired turbine vs coal vs hydro vs nuclear vs solar panels vs battery banks vs back gensets vs wood fired cooking/heating vs etc.... (in the SF Bay Area, the claim is that wood heating--maybe 5% of the homes using wood vs natural gas/electric, outputs more particulate pollution than all the automobiles and diesel trucks--after the improvements in smog control--if I recall correctly).

    Silicon processing has left many super fund clean up sites in the SF Bay Area--Looking at stuff being mfg. and resulting pollution in China is just plain scary (worse than former USSR and Eastern European block scary?). Much of that "Green Gear" is being made in China now.

    I don't think we will come up with a single "authoritative" answer. But, conservation is certainly well on the way to walking more softly on the planet.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies

    Off-grid solar power is greener than the equivalent Wattage produce by a nasty ol' fossil-fuel burning generator.
    Remember that they can't be built without generating pollution either. Size the system well, and for heaven's sake conserve as much as possible.
  • PhotowhitPhotowhit Solar Expert Posts: 4,956 ✭✭✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies
    icarus wrote: »
    Not to get into a P*&***g contest, but do you have any documentation for that statement? My hunch ( and it is only that) that that is a urban myth. If batteries are recycled what does it really cost (energy wise) to build batteries? (and PV).

    Tony, I'll first agree witrh BB and suspect you and I live on tiny amounts of Electric compered to most, I too use 15-20 KWhrs 9 months out of the year, and through conservation I will claim to be 'Green'

    Here is a study from 1990 using the panel design most comon yet today of cells cut from cylinders. They claim a payback of 86-84 months for a grid connected system.

    http://www.csudh.edu/oliver/smt310-handouts/solarpan/pvpayback.htm

    With drawn cells like Evergreen's and Amorphous cells minimal use of silicon this can get cut down to 18 months or so. This is for the best panels, here the Dept of Energy report;

    http://www.nrel.gov/docs/fy04osti/35489.pdf

    Without backup power off grid solar must have panels for the least available sun typically 1/2 of the most productive time of year, and storage to sustain power through periods of cloudy days lets say minimum of 3, storage is roughly 60% effiecient off grid(you and I know load shifting is a way of life off grid so I won't use the 53% often stated) so if N = Array 100% productive attached to grid, Nx2 + 3N x .6 = almost 4x the Array for off grid.

    So you/I waste 4x the power of a grid connected system before you add in the costs of building, transporting, recycling batteries.

    If you start with the majority of panels and use the Feds numbers of 3-4 years energy payback, off grid starts with a 12-16 year pay back on panels before batteries are considered.

    An idiot like my self it's much more wasteful as I run an AC in the summer, hence the 1300 watt Array goes largely wasted 9-10 months out of the year, as I sip maybe 700 watthours a day. Running a small fridge, a compact florecent bulb, mp3 player, a laptop an hour or 2, and a TV a couple hours...

    If I'm an idiot, the $25 user fee of the local Power Co before you buy any electric is really rough, making it cost effective to be off grid with power lines helping protect my Array from lightning stricks...lol.

    BTW - It maybe that panels have a much longer life than is suspected, I have some 55 watt panels made in the late 70's that are producing @ 80% of their rated amperage, some day I'll put them on an mppt meter and see about their total output. a 50 year+ life span might make a difference.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • icarusicarus Solar Expert Posts: 5,153 ✭✭✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies

    I am not arguing that off grid PV is energy efficient per se, as I under stand enough of the efficiencies to realize that you get ~1/2 as much power net/net out of a battery based system compared to a similar sized system.

    The question is; is it "greener to generate needed power, store it in a battery and use that power as needed, or is it more green to produce that power with fossil fuel?

    Once again, I certainly can't quantify it, but my suspicion is that it has to be "greener" to use Pv rather than fossil.

    Tony
  • nielniel Solar Expert Posts: 10,311 ✭✭✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies

    tony,
    i believe that being both scenarios have battery storage it becomes a question of, what is 'greener' pv or fossil fuel? if greener means less pollutants for the power then it is pv hands down. if you base it with costs per kwh then it's fossil fuel. 'greener', as loosely a term used as it is, never referred to less costing that i know of.
  • BB.BB. Super Moderators, Administrators Posts: 29,332 admin
    Re: Completely Green - Need Help with Basic Setup and Supplies

    A few years ago, there was a company that was charging $1-$2 per watt to disassemble old solar crystalline silicon PV panels and safely recycle/dispose of them...

    Back when panels cost $10 per watt--I guess you could justify those prices.

    Now with panels at $2.50 per watt--who would pay $2.00 per watt to "safely" recycle?

    Here is a pretty good article that lists the various hazardous waste streams (besides lead and copper, some thin film technologies include cadmium), but it sounds like nobody is ready for a large stream of panels that eventually hit end of life. In the end, may just strip external metal frames and hazardous landfill the rest of the panels.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • nielniel Solar Expert Posts: 10,311 ✭✭✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies

    bill,
    as i said, the way i understand being green is that it is not necessarily the most cost effective. we here try to be practical with costs too, but it is not always inline with being green. i interpret being green as having a lesser negative impact on the environment and that is not always the cheapest route. your example is one that is not cost effective, but may be greener to recycle than make a brand new pv. i agree to buy the new pv even though it's not as green to do.
  • russruss Solar Expert Posts: 593 ✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies

    My experience is that if people have to pay out of their pocket to 'properly' dispose of something you will find it in the garbage bin.
  • BB.BB. Super Moderators, Administrators Posts: 29,332 admin
    Re: Completely Green - Need Help with Basic Setup and Supplies

    In California--we have various recycling laws that attempt to address the cheap landfill option. $0.05 to $0.10 per drink can/bottle (return for cash) and an Electronic Displays (TVs, computer monitors, etc.) in the $8-$25 range ("free dumping"). We also pay $10 deposit for car batteries (do not know if applies to other types).

    Do not know what the "costs" would be for Solar Panel and Inverter recycling that the state would put into law.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • PhotowhitPhotowhit Solar Expert Posts: 4,956 ✭✭✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies

    To Neil and Icarus,

    At no point am I considering costs only the "Energy" payback, likely the panels are made using fossil fuels, batteries recycled using fossil fuels...

    Hence I'm only looking at the fossil fuel "energy cost's" of a solar panel.
    Photowhit wrote: »
    Tony, I'll first agree witrh BB and suspect you and I live on tiny amounts of Electric compered to most, I too use 15-20 KWhrs 9 months out of the year, and through conservation I will claim to be 'Green'

    Here is a study from 1990 using the panel design most comon yet today of cells cut from cylinders. They claim a payback of 86-84 months for a grid connected system.

    http://www.csudh.edu/oliver/smt310-handouts/solarpan/pvpayback.htm

    With drawn cells like Evergreen's and Amorphous cells minimal use of silicon this can get cut down to 18 months or so. This is for the best panels, here the Dept of Energy report;

    http://www.nrel.gov/docs/fy04osti/35489.pdf

    Without backup power off grid solar must have panels for the least available sun typically 1/2 of the most productive time of year, and storage to sustain power through periods of cloudy days lets say minimum of 3, storage is roughly 60% effiecient off grid(you and I know load shifting is a way of life off grid so I won't use the 53% often stated) so if N = Array 100% productive attached to grid, Nx2 + 3N x .6 = almost 4x the Array for off grid.

    So you/I waste 4x the power of a grid connected system before you add in the costs of building, transporting, recycling batteries.

    If you start with the majority of panels and use the Feds numbers of 3-4 years energy payback, off grid starts with a 12-16 year pay back on panels before batteries are considered.

    An idiot like my self it's much more wasteful as I run an AC in the summer, hence the 1300 watt Array goes largely wasted 9-10 months out of the year, as I sip maybe 700 watthours a day. Running a small fridge, a compact florecent bulb, mp3 player, a laptop an hour or 2, and a TV a couple hours...
    I only included this to explain why I'm not grid connected...

    Photowhit wrote: »
    If I'm an idiot, the $25 user fee of the local Power Co before you buy any electric is really rough, making it cost effective to be off grid with power lines helping protect my Array from lightning stricks...lol.


    BTW - It maybe that panels have a much longer life than is suspected, I have some 55 watt panels made in the late 70's that are producing @ 80% of their rated amperage, some day I'll put them on an mppt meter and see about their total output. a 50 year+ life span might make a difference.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • icarusicarus Solar Expert Posts: 5,153 ✭✭✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies

    PW

    "At no point am I considering costs only the "Energy" payback, likely the panels are made using fossil fuels, batteries recycled using fossil fuels...

    Hence I'm only looking at the fossil fuel "energy cost's" of a solar panel."

    No offense, but if one is arguing about the "greenness" of a technology one has to take into account more than just the monetary, out of pocket price of the fuel. I agree that we can (and do) get bogged down in what to account for and how and why to account for it but there are some things that are fairly simple to account for in this conversation.

    So going back to your post #4 about off grid being "not green" might be reworded to read, not cheap (compared to fossil fuel). I don't have any real idea of what the right answer is, but I think it a bit cavalier to suggest that off grid solar is "less green" than fossil fuel based.


    The real green equation is, IMHO, how we use our energy as much as how we "make" our energy. I go back to my old argument, there is little green in building a solar powered McMansion, only to burn incandescent bulbs. Said house may use "greener" energy, but waste is still waste, and the house would be much "greener" if the house itself were more efficient, and if it were to then sell that surplus to the grid.

    Tony
  • PhotowhitPhotowhit Solar Expert Posts: 4,956 ✭✭✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies

    You missed my whole point, I'm NOT talking about the monitary costs but the fossil fuel costs...

    Example it 'costs' 15 watts to run a compact florescent lamp for an hour...

    If takes 400 calories to run for an hour, that is a value or 'cost'.

    Hence the term 'Energy payback' has nothing to do with money.

    I'm using energy as a value, as does the Gov Doc and the other study.

    Don't get hung up on my use of the word cost, The cost of war can be measured in the loss of innocence...
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • icarusicarus Solar Expert Posts: 5,153 ✭✭✭✭
    Re: Completely Green - Need Help with Basic Setup and Supplies

    PW,

    I got it now,, I missed the link. I might argue the conclusion however. Assuming that battery based PV is ~1/3 as efficient as grid tie, and if grid tie has a pay off of 3-4 year, then it would follow that off grid would be 12-16 as you suggest. I suspect that this doesn't very accurately reflect many of the fossil fuel costs associated with off grid. For example, generator efficiencies that are running at less than 100% load, but are likely using 100% fuel for example. ( Or more accurately running at say 50% load but burning ~100% of the fuel.)

    There is no argument that off grid installations are very much less efficient than a grid tie system, no matter how it is fueled. All one has to do to confirm this is look to any northern community in Canada that relies on Diesel generators.

    It also depends to some extent on whether or not the system is used 24/7 365 vs part time. You source also doesn't take into account the environmental cost of batteries, their manufacture, disposal and recycling. Factor that in to get a "green cost", but also factor in the environmental costs of fossil fuel, it's extraction and refinement, it's carbon load etc, plus the cost of building, maintaining generators and their disposal and only then can one get a real idea of the "greenness" of any system.

    Tony
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