Ballpark $ figure to get 2000KWh a month? Commerically installed?

Mike 01Hawk
Mike 01Hawk Registered Users Posts: 5
Hey gang, found this site after goggling around for the Skystream 3.7. Sounds to me the limited 400KWh on a GOOD month would not even touch a 1/4 of our power needs during summer peaks.

Here' s our power usage so far, we've only been in this house since June of 2009. Of course the "Per KWh" is after all the local taxes and what not.
Date          KWH        $	     Per KWh
10/12/2009	  955     $75.21     $0.0788 
 9/11/2009	1,476    $108.65     $0.0736 
 8/12/2009	2,004    $145.93     $0.0728 
 7/14/2009	2,424    $175.79     $0.0725

Stats on our house:
  • Built in 1986 (wish it was newer :( )
  • 31 of 33 windows replaced this month with Viewpoint Series 3000 w/ optional Low-E Argon flim/gas. Average window has a U-Factor of 0.30 and Solar Heat Gain coefficient of 0.21.
  • 3300 square feet, 2 story
  • 2 zone Electric AC, Gas Furnace. Gas water heater. Electric Oven/Range, bummer, I know, I wish it was gas.
  • Have already replaced most of the 'always on' lights w/ CFLs

Stats on our location:
  • North East Oklahoma, outside Tulsa, zip code 74014
  • According to a little bit of goggling we receive on average 10mph winds. :(
  • Lot is 2.5 acre
  • Multiple trees are on lot, some as high as 30 feet. However there is one patch that is relatively 'tree' free. Would be a good spot for a solar array if roof wasn't enough.

What I'd like from Solar/Wind Power
  • Ultimately I'd like to have 'free' energy
  • Don't want to mess with batteries
  • Living 'on the grid' is fine
  • Would like to have the system to have paid for itself within 20 years, 10 years would be awesome.

So, as you can see, we've got the acreage for some energy providers. We could come up with the capital needed to go wind/solar. Here's my thing though, I don't want to invest $10-$15k+ into a system only to 'get back' a measly 400KWh a month.

Is there anyone on the board that has approached the 2000KWh month figure?

Should I just bide my time until this technology is more widely embraced?

TIA!!!

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    Well--there is no "free" electricity with solar PV grid tied systems either.

    Basically, to put your money in the areas where it will work hardest for your...

    First conservation. Reduce your electric loads as much as you can (turn things off, perhaps replace your current Air Conditioner with a more efficient unit, look at more insulation in the attic + weather stripping, etc.).

    For the "small loads" a Kill-A-Watt meter is a good deal. You may be surprised at how much power an old fridge in the garage, the entertainment center, those couple of desktop computers that are left on 24x7, etc. really cost you.

    For whole house loads, a T.E.D. system (or other similar contraption) may be worth looking at (by the way, the current TED's do not work correctly with Grid Tied power--they cannot tell if you are consuming or generating power).

    Also, if you use a lot of hot water (kids+showers+washing machines)--solar domestic hot water heating can be a good investment too. Can be a good project if you are a hard-core do-it-yourself'er (and into plumbing).

    Now, you are down to Grid Tied solar and spending any "extra" money on that project... However, it will be hard pressed to come near your current utility power pricing (mine in California can range from $0.09 to $0.60 per kWhr for Residential power, and upwards of $0.75 per kWhr for Commercial). For Grid Tied solar you may get near $0.10-$0.15 per kWhr or so after rebates and tax credits.

    Using the PV Watts program and 1kW of solar panels (round numbers) for Tulsa (used defaults for rest of configuration):
    "Station Identification"
    "City:","Tulsa"
    "State:","Oklahoma"
    "Lat (deg N):", 36.20
    "Long (deg W):", 95.90
    "Elev (m): ", 206
    "PV System Specifications"
    "DC Rating:"," 1.0 kW"
    "DC to AC Derate Factor:"," 0.770"
    "AC Rating:"," 0.8 kW"
    "Array Type: Fixed Tilt"
    "Array Tilt:"," 36.2"
    "Array Azimuth:","180.0"

    "Energy Specifications"
    "Cost of Electricity:"," 7.7 cents/kWh"

    "Results"
    "Month", "Solar Radiation (kWh/m^2/day)", "AC Energy (kWh)", "Energy Value ($)"
    1, 4.01, 97, 7.47
    2, 4.46, 95, 7.32
    3, 5.33, 122, 9.39
    4, 5.88, 128, 9.86
    5, 5.61, 122, 9.39
    6, 5.77, 118, 9.09
    7, 6.06, 126, 9.70
    8, 5.95, 125, 9.62
    9, 4.99, 105, 8.09
    10, 5.41, 122, 9.39
    11, 4.11, 92, 7.08
    12, 3.70, 88, 6.78
    "Year", 5.11, 1339, 103.10

    We can compare July of yours to a "typical" July using 1kWatt of solar panels:

    2,424 kWhr per month / 126 kWhrs per month (per 1kW solar) = 19.2 kWatts of solar panels

    Which will cost you (very roughly--I am not in the solar biz) $6-$10 per watt installed and you will get 30% back in Federal Tax credits and whatever your state and local credits may be.

    So, you are looking at (very roughly, assuming $7,000 per kWatt installed price) around $7,000*0.70*19.2kW = $93,000

    Such a system would generate around:

    1,339 kWhrs per year per 1kW of panels * 19.2 kW of panels = 25,709 kWhrs per year

    Assuming a 20 year pay back period (no interest or maintenance):

    $93,000 system cost / (25,709 kWr per year * 20 years) = $0.18 per kWhr

    Note that sizing of a GT system typically is based on offsetting 1 year worth of power bills... So your system may be larger or smaller than I indicate here (which was done based on your July power bill).

    Regarding shading, you pretty much need clear of shadows/trees for, at least, 9am-3pm. The more shading you get, the more the total system output will suffer (more sun is better).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Mike 01Hawk
    Mike 01Hawk Registered Users Posts: 5
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    Bill,

    Thanks for running the rough numbers.

    Soooooooo.... basically you're saying I should be thankful I'm only paying 7c a kWhr?!?!?!?! Ha! 18c which is more than double what I'm currently charged just doesn't seem worth it from a financial stand point.

    Hmmm. I may see if there's a local sales rep that could come to my house and demo the #s for me, since I'm assuming they'd know the local laws/rates better.

    Ah, to be early adopters, what a pain!
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    And you are really not even in the early adopter's phases any more... The hardware, rules, and regulations have gone through multiple iterations by now and it is pretty cookie-cutter now to get a system quoted and installed (excluding issues with electric utility and sometimes Home Owner Associations).

    Prices for hardware have probably hit bottom for now (unless there is something that cuts the costs by 1/2--which is probably not on the table for home solar PV systems at this time). And there are significant strains that are pushing prices up (cost of raw materials, copper, falling US dollar, increasing taxes, and increasing costs of fuel).

    In any case--conservation will be worth your time and energy right now. And, perhaps, plumbing in a natural gas range would help too.

    It sounds like most of your costs are probably A/C--Getting a good evaluation of your home's state of insulation and current efficiency of your A/C pump would be a good place to start.

    Reducing your overall energy usage by 1/2 (from an original home with little concern for conservation--i.e., neighborhood average) is not an unreasonable goal. But pick on the "big stuff" first--forcing everyone to unplug cell phone chargers with a 2,000+ KWhr per month electric bill is not going to do anything except to tick-off the spouse and kids.

    -Bill

    PS: Remember, if you are using A/C--every watt of power you save inside the conditioned envelope of the home is a watt you don't have to pay to have the air conditioner move the heat to outside the home. So conservation can pay twice for you in the summer months.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    As bill suggests, it is not "early adopters" that is the issue. As has been so often suggested, every dollar spent on conservation will save ~$10 in Pv costs. The reality is that at $.07/kwh it makes it really hard for Pv solar to compete. One of the issues that we have to gamble upon is what is the price of electricity going to do over the live cycle cost of the system. Clearly, if past history, (and current politics) is any guide, I think it is a safe assumption that the price of all energy is going to go up, and potentially up a lot in the coming decades.

    If it were me, and I wished to move forward, I would do EVERYTHING I could do to conserve every bit of energy I could. Then I would install solar hot water (which is very much cheaper per BTU than PV) Then I would take every advantage of tax credits/utility rebates to get the best KWH price for an installed system. (I would also spend some time lobbying my local governments and utilities to encourage Pv solar by encouraging net metering, time of day metering etc.)

    So continue to do your homework, figure out how to reduce your loads.

    Good luck,

    Tony
  • Windsun
    Windsun Solar Expert Posts: 1,164 ✭✭
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?
    Ah, to be early adopters, what a pain!

    If you notice on our website, this is our 30th anniversary, so hardly an early adopter :blush:
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    For your property the best dollars spent would be

    Insulation, R40 minimum for the attic

    AC/Heat , install a ground based geothermal unit, which can can heat and cool with COP's in the 25 range, they also can provide the domestic hot water

    At your price of electric, no solar or wind would have a payback in your lifetime
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    At your price of electric, no solar or wind would have a payback in your lifetime

    At CURRENT price of electric..... ( $0.0788 )
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    In California (and probably other places like New York)--the average price of residential power works out to ~$0.30 - $0.35 per kWhr or so for those high levels of usage (and heading up).

    I am not convinced that you would be well served spending a $100,000 to hedge against high power costs in the future.

    If you have to move (whatever reason)--it is difficult to take the system with you--and unlikely to increase the value of your home by anywhere near $100,000... Not many buyers are willing to pay a premium for solar hardware (even I would be hard pressed to pay more than about 1/3rd of your out of pocket expenses for such a setup).

    Add the issue that the state/utilities can easily change the whole rule set that make Solar Grid Tied systems cost effective for consumers at this point in time--it possible for them to make even existing systems more economically viable to not install in the first place--or even to unplug (California/PG&E has done both of those over the last few years--only to back off when they almost killed the entire solar PV GT market).

    At least with conservation--you own the insulation and appliances. And a "remodel" frequently adds to the future value of the home (50%-100% of outlays). And no arbitrary state rule changes can wipe out the value your investment (well, not entirely true--there are noises about new federal rules that require new levels of conservation/efficiency before a home can be resold/get a loan).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Mike 01Hawk
    Mike 01Hawk Registered Users Posts: 5
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?
    Which can can heat and cool with COP's in the 25 range

    COP? What's that stand for?

    And yes, insulation and Geo will probably be the next things we do. Although it's gonna take us a while to 'regroup' from the $10k investment we did in windows.
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    In the absence of a ground source/ground water heat pump, consider converting to Propane. (Although at $.07 kwh it is still hard to make it pay). Propane for cooking/heating and demand water heating will likely be cheaper than resistance electric.

    You also comment in your first post that "the always on lights have been converted to CFLs" Why only the "always on" and not virtually all? Unknown to many, there are CFL styles that mimic almost all bulb styles and Kelvin colours, from little 3 watt candellabra bulbs to Par reflector spots and floods. There is really no reason not to change them all to CFLs (Also in the real world, why do any bulbs need to be "always on"? Motion detectors, body heat activated wall switches etc can provide all the convenience of always on but without the waste.

    A final question is more rhetorical: How come your utility cost is so low? $.07 must be near the lowest electricity cost in N. America.

    Tony

    Cop is a way of measuring Air cond. efficiency: SEER is related to the coefficient of performance (COP) commonly used in thermodynamics and also to the Energy Efficiency Ratio (EER). The EER is the efficiency rating for the equipment at a particular pair of external and internal temperatures, while SEER is calculated over a whole range of external temperatures (i.e., the temperature distribution for the geographical location of the SEER test). SEER is unusual in that it is composed of an Imperial unit divided by an SI unit. The COP is a ratio with the same metric units of energy (joules) in both the numerator and denominator. They cancel out, leaving a dimensionless quantity. Formulas for the approximate conversion between SEER and EER or COP are available from the Pacific Gas and Electric Company:[1 (Wiki)
  • Mike 01Hawk
    Mike 01Hawk Registered Users Posts: 5
    CFL conversion isn't complete mainly because of aesthetics of some of the bulbs, plus I like to have 'instant-on' for a few things, such as closets.

    Now that I think about it, I could probably change most of the 'instant-on' to those spiral 40-60w equivalents, their warm up time is virtually nill... on second thought, I guess it's just mainly astethics and $ of the bulbs. I figure since I don't use some of the lights that much, the cost of elec vs the cost of the bulb doesn't make it worth while.

    And I have no idea why OK is so cheap, maybe cause we have so much natural gas?
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    As for the aesthetics, like I said, there are bulbs of every physical/color description,,, and the price has come way down. http://www.nolico.com/saveenergy/

    Tony
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    My wife hates CFL's--but she does like the low electric bill and keeping our home cool in the hot summer nights (we sometimes have) without needing to use an A/C system (most homes in our area do not have A/C).

    Our local Utility (PG&E) subsidizes CFL's to almost 1/2 off in our stores--so they cost around $1-$2 each retail for standard 11-23 watt twisties.

    We have gotten used to them--to the point now when we can really feel the home warming up if we turn on some of the other fixtures (chandler with 40 watt bulbs, some ceiling cans with halogen bulbs that my wife will just not let me change to CFL because they are so "ugly").

    I have (to may wife's complaints) put 7 watt candelabra CFL's in one hanging fixture in our living room (that does not have a dimmer installed)--it just keeps the room so much cooler and we can use a reading lamp or can fixtures for when they really want "good light". And there are lots of complaints while it takes a few minutes to warm up to full output.

    CFL performance is just so unpredictable... What used to be pretty quick on becomes a slow warm/horrible color up the next time I purchase the same package. I have gotten to the point where I purchase a couple 6-packs of CFL's for later use when I find one that works well.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    Not all fixtures are suitable for CFL. In fine print, the CFL package will state, base down, open air. Any other configuration, they burn out early. This eliminates most ceiling fixtures, the heat build-up cooks the bubs to death. Ever notice the browned plastic bases ??
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?
    COP? What's that stand for?

    And yes, insulation and Geo will probably be the next things we do. Although it's gonna take us a while to 'regroup' from the $10k investment we did in windows.

    http://en.wikipedia.org/wiki/Coefficient_of_performance

    Short explanation is energy in to get heat/cooling out. The higher the number the better the devices is at extracting energy from the Air/Ground.

    Resistive base board electric heaters for example are a COP of 1. Since GeoThermal is extracting energy from the medium of the ground or water, its very efficient as compared to the electric to run the compressor and or loop pump.

    If you can't afford this, there is little reason to even discuss ( consider maybe a better word ) solar or wind as they are orders of magnitude more expensive.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    CFL's don't like bathroom (humidity) fixtures either--but I still use them there.

    Frankly, for the most part, 2/3'rds of my CFL's seem to last pretty well, and 1/3rd die early deaths (year or so). And does not seem to matter if installed in a garage (cool, dry, not used too much) vs bathroom with lots of on time and cycling. :confused:

    Seems to be mostly die from electronic ballast circuit failures.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    I've had two failures in 10 years, both in the last week, both in base up fixtures,

    t
  • Mike 01Hawk
    Mike 01Hawk Registered Users Posts: 5
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?

    Well holly crap!!! I had an AMAZING discovery today!!! Hyper hyper!!!!!

    So, it's now fall, fall = less/no leaves on the trees. Meaning I can see more stuff around my house. I can even clearly see the Coweta Power plant from my back yard. Anyway, I go out side to do some yard work this morning, and what the hell do I see???? In my neighbor's yard a couple houses down???? TWO VAWTs!!!!!!!!!!!!!!!!!! HOW FRIGGEN AWESOME IS THAT?!?!?!?! I couldn't even feel the wind blowing this morning and those suckers were spinning like crazy.

    Now all I need to do is go schmooze on up to my neighbor and pick their brains to death. I couldn't ASK for a better 'real world' scenario! I'll know exactly what kind of #s I'll get if I install one on my property.

    It's like a sign or something, lol!

    Anyway, once I get the guts to go randomly knock on a strangers door I'll get back w/ the info I gleam.
  • bryanl
    bryanl Solar Expert Posts: 175 ✭✭✭✭✭
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?
    Add the issue that the state/utilities can easily change the whole rule set
    Which is why it is tough to determine the actual cost of energy.

    Somebody's got to pay for it one way or another and the real question involves who and how much. Right now, a lot of the 'alternate' energy sources are being paid for by 'someone else' in the form of subsidies, tax credits, and regulations all up and down the line. It is rather sad that so much innovation has gone into this area rather than into the technologies involved.

    Craig's List had a 6kW system for sale for $60k if I recall correctly. I had in mind $4 per installed watt rather than the double that cited here to figure that price a bit high.

    The talk about reducing one's energy budget has to keep in mind that we spend what we can afford to live comfortably. Punishing one's self for some arbitrary rationale is not necessarily a sane thing to do. There is always a need for a balance between objectives and needs and wants.
  • Windsun
    Windsun Solar Expert Posts: 1,164 ✭✭
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?
    bryanl wrote: »
    Craig's List had a 6kW system for sale for $60k if I recall correctly. I had in mind $4 per installed watt rather than the double that cited here to figure that price a bit high.

    At this stage, you simply are not going to see any real installations at $4 per watt, even with the massive subsidies in some areas. As solar panel prices have dropped, everything else has gone up - including the fees that local jurisdicitions charge just to get approval. The price of metals has gone up despite the recession, so such things as mounts and wire are costing considerably more.

    We installed our first grid tie system somewhere around 1999, total fees were around $75. The last one we did cost over $1900 just in fees payable to some entity, and it probably cost us another $2500 or so in time and manpower.
  • tallgirl
    tallgirl Solar Expert Posts: 413 ✭✭
    Re: Ballpark $ figure to get 2000KWh a month? Commerically installed?
    So, it's now fall, fall = less/no leaves on the trees. Meaning I can see more stuff around my house. I can even clearly see the Coweta Power plant from my back yard. Anyway, I go out side to do some yard work this morning, and what the hell do I see???? In my neighbor's yard a couple houses down???? TWO VAWTs!!!!!!!!!!!!!!!!!! HOW FRIGGEN AWESOME IS THAT?!?!?!?! I couldn't even feel the wind blowing this morning and those suckers were spinning like crazy.

    "Spinning like crazy" doesn't mean "making power like crazy".

    There's only so much power in moving air, and if you can't feel it, there's very little power.