When is BreakEven?

nnsharda
nnsharda Registered Users Posts: 10
Electricity cost is 13 cents per KW/Hr here in Las Vegas.

If a Solar Panel costs $2/W, (200 W panel for around $400), and there is 6 Hrs sunlight per day on average, then the total production ideally would be 1.2KW per day, thus producing at maximum 15 cents of power a day. Thus, it would take 2,667 days or 7.3 years just to pay for the solar panels.

I have read in this forum, however, that the true net usable power is closer to 60% of what is produced due to line loss, heat, inverters, battery loss etc. Thus we are now at 12 years, without factoring in the price for installation, charge controller, inverter, grid tie systems or batteries.....or broken panels or other maintainance issues.

Thus solar seems completely unaffordable for the average guy....

I hope I am wrong in my calculations...please help

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    Re: When is BreakEven?

    Not far off... We can use PV Watts to get a more accurate estimate of energy generation... I use 0.77 derating but you may get upwards of 0.82 or so with the right equipment, higher altitude, clean panels, etc...:
    Results
    
    Month     Solar Radiation
    (kWh/m 2/day)     AC Energy
    (kWh)     Energy Value
    ($)
    1      5.19          119        11.54   
    2      5.98          121        11.74   
    3      6.57          147        14.26   
    4      7.32          155        15.03   
    5      7.42          157        15.23   
    6      7.35          145        14.06   
    7      7.37          148        14.36   
    8      7.29          147        14.26   
    9      7.31          144        13.97   
    10      6.56          141        13.68   
    11      5.75          125        12.12   
    12      5.05          115        11.15   
    Year      6.60          1664        161.41 
    

    A 1 kW GT system would generate around 1,664 kWH per year
    • 1,664 kWH per year * $0.13 per kWH = $216 per year
    Assuming $5 per watt installed (turnkey system, at least 3kW in size), less 30% federal tax credit would cost you $3.50 per Watt installed or $3,500 per kW of array:
    • $3,500 installed / $216 per year power cost = 16.2 years
    In California where people can pay upwards of $0.50 per kWH in the summer (those with A/C and water pumping costs), the payback can be much quicker.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • solar_dave
    solar_dave Solar Expert Posts: 2,397 ✭✭✭✭
    Re: When is BreakEven?

    You may want to look at the TOU rates to reduce your costs
    http://www.nvenergy.com/company/rates/snv/schedules/images/Statement_Rates_South_000.pdf

    Your night rates are about half that 13 cents. Your solar offsets your on peak rate of 29 cents. You could cut your bill in half by gaming these rates and load shifting. If you are using electric for water heating look at solar thermal. In any case conservation is your best investment, cheaper to save a watt than generate or buy a watt. Do all the standard stuff, CFLs, more insulation, higher seer AC units, energy star appliances first. Check with your utility for help with conservation.

    Get a good solar contractor and have them run the numbers. Installs are as low as $4.25 a watt before tax savings and rebates and pre paid leases are as low as a $1 a watt in Phoenix. YMMV and Phoenix utilities provide incentives.
  • Seven
    Seven Solar Expert Posts: 292 ✭✭
    Re: When is BreakEven?

    Without factoring in rebates and such your math looks right to me. Solar isn't cheap. That is not the selling point. Never has been. Solar is not right for most on-grid people. If you are in a location that does not currently have electricity and getting the power to the place is not possible, solar is a way to go. Sometimes the expense of getting power lines ran can cost more that a solar array would. How long is 12 years to you? The panels should last twice that long. At the end of the 12 years you are even as far as cost, replacement parts excluded. What then? Your panels are paid for and you have recouped the money you spent, so now the electricity they produce is a net gain.

    Cost isn't the only factor some people consider. How about: going green, saving the planet, reducing your carbon footprint, reducing our dependence on foreign oil, etc. Some even view solar as a hobby.

    By building a PV system you gain knowledge, experience, you get to work with your hands, your brain starts using math again, you get some protection from rising energy prices, and alot of other good things.

    What is the real break even when you consider all of this.........
  • TnAndy
    TnAndy Solar Expert Posts: 249 ✭✭
    Re: When is BreakEven?

    And add to the above, if the grid goes down due to an attack, or another Carrington event, or simply because the bubble gum/bailing wire holding parts of it together finally give out, I plan to live closer to the 20th century than one of those previous ones. And if that happens, NOBODY will be giving a crap about payback period.

    To each, their own.
  • rollandelliott
    rollandelliott Solar Expert Posts: 834 ✭✭
    Re: When is BreakEven?

    "Thus, it would take 2,667 days or 7.3 years just to pay for the solar panels. "

    just curious how long did you think the payback period was going to be?

    I get the feeling most people think it is over nite.

    Seriously I think most people think they buy solar panels install them and they immediately generate so much electricity they will be making $$$$.

    Just wondering if my gut feeling is right?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    Re: When is BreakEven?

    If people believe all the radio ads, it sounds like it should be a few years.

    And if people go with the solar leases, it actually can save some money immediately. Of course, that is possible because of the investment and tax treatment laws that a company can take that an individual frequently cannot.

    There are some, apparently, pretty good lease to own deals out there right now (buy your system for $1 after X years) with not too much money upfront/per month... So those do not look bad.

    But, so much of Grid Tied Solar depends on local utilities and state laws/regulations, that simple $$/kWH pricing is not "good enough" to work out a return on investment.

    Between (typically) smaller co-ops that do not support GT on their systems, and places like California that can take several pages to describe the billing plan (and not even mention how it works with solar and tiered rates), add commercial plans with various tiers, requirements, and installed equipment surveys--Asking about ROI (return on investment) is actually quite a good question--and one that few of us here can give any more than a simple estimate as an answer (many times, even that is almost impossible without calling the utility or even hire a local consultant to figure that out).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • nnsharda
    nnsharda Registered Users Posts: 10
    Re: When is BreakEven?

    Well, I seem to have offended some people, not my intention. Each person has his own religion....

    I was just trying to get a handle on cost for an average guy in the city prior to making a fairly large monetary decision.

    Heck, most of us move every 7 years on average anyway so 12+ years does seem like a lot of time to recoup an investment, and we can only hope that the buyer appreciates the advantages of solar the same way we do.

    I do thank the posters who recommended some rational solutions such as increasing insulation, hot water solar, shifting to off peak usage and gas powered generators in addition to solar panels.

    Will keep studying for now:D
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: When is BreakEven?

    i don't think anybody was actually offended here. they came off with that as it is more obvious to us what the score is, whereas you just came to the realization that it can be quite expensive to do. solar is not for everyone and reasons do vary for getting it.
  • rollandelliott
    rollandelliott Solar Expert Posts: 834 ✭✭
    Re: When is BreakEven?

    "Heck, most of us move every 7 years on average anyway so 12+ years does seem like a lot of time to recoup an investment, and we can only hope that the buyer appreciates the advantages of solar the same way we do."

    Well the only way you are going to beat the system is by educating yourself enough to install the solar yourself. With bankrupt panels goiing for $.78/watt inverters going for $.40/watt racking systems @ $.20/watt and miscellaneous costs you can buy everything for around $1.60 a watt now a days,

    minus the 30% fed credit and your payback could be around 5 years.

    also many rebate programs are available in CA.

    call up an expert local installer and they will be able to tell you if any apply to you.
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: When is BreakEven?

    Where are you seeing $.78 per watt on PV?
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • TnAndy
    TnAndy Solar Expert Posts: 249 ✭✭
    Re: When is BreakEven?

    It's a competitor to AZ Sun/Wind, so let's do them the courtesy of not posting the name, since they sponsor this website, but yes, they ARE out there.
  • dgsloan
    dgsloan Registered Users Posts: 22
    Re: When is BreakEven?

    Problem is nobody considers compound savings. You never start with the solar panels but as you save the money from your last energy project you spend it on the next thing that will save energy at a lesser rate = We all have to retire sometime. Getting rid of that gas guzzler is probably near the top. An inexpensive convenient mode of transportation may be an electric bike. After I saved in the first year enough to pay for the bike I took the next 1k dollars and bought some solar panels - why - because if everybody starts charging their car / bike the rates will eventually increase. As said by previous posts - do it yourself is evolving to reduce the cost of installation. There is enough on the internet that this is a doable task. Just do not get sucked in by cheap / inefficient converters and crazy cheap panels. It took two years to save the money but after installing 8 months ago I will be in the megawatt club by Christmas. Oh and yes it will take 10 plus years to save at the projected levels and costs today - but keep reinvesting and you will retire earlier than later. http://enlighten.enphaseenergy.com/public/systems/K9u718705
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: When is BreakEven?

    TnAndy, I fully expected the answer to be PMed for that very reason, and in fact somebody already did. :roll:
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • rollandelliott
    rollandelliott Solar Expert Posts: 834 ✭✭
    Re: When is BreakEven?

    techntrek,

    At the solyndar bankrupcency auction yesterday, people were snagging those up at 20 cents a watt! Makes the evergreen panels look like a rip off. LOL

    Problem is solynbdra's "panels" are really only practical for flat roof installs and not your typical residential application.....

    Unforunatley I doubt these are the last solar companies to go bankrupt, so more deals on the way!
  • nnsharda
    nnsharda Registered Users Posts: 10
    Re: When is BreakEven?

    Well, if anybody has a lead on those Solyndra panels at 20 cents a watt let me know, because I do have a flat roof here in las vegas, and that would absolutely make it reasonable.

    I suspect, however that this is just another talking point. Never seem to get the deals that people talk about, wonder if they really happened......

    Thanks for a great discussion and lots of knowledge everybody.


    Nav
  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    Re: When is BreakEven?

    I have a friend who was watching the auction over the Internet--And the prices for machinery, office furniture, etc. was going quite high on average... Some of it over retail. Apparently it got lots of notice and attracted lots of buyers.

    -Bill :confused:
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • rollandelliott
    rollandelliott Solar Expert Posts: 834 ✭✭
    Re: When is BreakEven?

    "I suspect, however that this is just another talking point. Never seem to get the deals that people talk about, wonder if they really happened."

    well the evergreen auction, had the smallest amount of panels at 1/2 a container or 30KW.

    Unless you buy a truck load you aren't going to get the good deals.

    You'd be beter off seeing if there are any local or utility rebates in your area by calling around to solar installers.

    If you don't do your homework, it is pointless to cry sour grapes.
  • jagec
    jagec Solar Expert Posts: 157 ✭✭
    Re: When is BreakEven?
    nnsharda wrote: »
    Well, if anybody has a lead on those Solyndra panels at 20 cents a watt let me know, because I do have a flat roof here in las vegas, and that would absolutely make it reasonable.

    I suspect, however that this is just another talking point. Never seem to get the deals that people talk about, wonder if they really happened......

    I'm sure they happen...you just gotta know someone. Always seems to be the case with below-market pricing.
  • ggunn
    ggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: When is BreakEven?

    Seven years is actually pretty good. You did, however, mention batteries. A battery backup system will never pay for itself in purely economic terms.


    Solar is a long term investment.
  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    Re: When is BreakEven?
    nnsharda wrote: »
    Heck, most of us move every 7 years on average anyway...

    Wow! Another indicator just how out of touch with the norm I am! :confused: I'd never have thought that was the average, but after I read it I went searching and sure enough... (Some say the average is *5* years!) Been in my house 8 years (and lived in this community all my life), no intention of moving. My parents have been in their house over 30 years now. Guess we're just weird! (The thought of moving my stuff that often makes me nauseous! :cry: )

    As for break-even, I did a full analysis on my system. Self-installed, so no labor. 1080W in panels, 48V 220AH battery bank, Outback electronics. With my ultra-cheap grid power rates, it would take something like 54 YEARS to pay back - if nothing dies! Something tells me I'll be going through a few sets of batteries between now and then, and I doubt the other stuff makes it that long.

    So effectively it'll never pay for itself, unless grid rates skyrocket in the near future.

    But I didn't put it in for that reason anyway - I wanted a little self-sufficiency to keep the basics going in an outage, and I just have fun tinkering with it in the meantime! :cool:
  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    Re: When is BreakEven?

    For budget planning--I would assume inverters, charge controllers, gensets (digital sections, inverter/generators), etc. every 10 years.

    Even if they are repairable--The electronics and parts can be very difficult to find after 10 years (most stuff is obsolete or no longer made).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset