The cabin Appliance's list so far to run off a off gid cabin

henry1henry1 Posts: 51Solar Expert ✭✭✭✭
Here is a basic list of appliance's and other items i'm planing to have in the cabin battery bank

110.volt
-Fulcum stand up lamp 10.amps draw per hour of operatio
-Mircowave oven-x-600.watts draw per hour of operation
-Induction 1800.watt cooktop burner-1800.watt draw per hour of operation
-Zojirushi Bread machine-700.watts draw per hour of operation
-Hair Rv style combo washer & dryer unit -600 watts draw per hour of operation
-2-sliced Toaster unit-1000.watts draw per hour of operation
-Reliance 6.gallon hot water heater 1650 watts draw per hour of operations
-Radio & scanner unit -45 watts draw per hour of operation

12.volt items
-Ipad car charger
-Dumb Cell phone car charger
-Diff led light's through out the place-x-8-diff areas with light's-16-watt's per hour of operation
-3.2.sized fridge for keeping thing's cold-14 watts draw per hour of operation
-Tailgater blender i found that 12.volts to make up my breakfast protein shake's in the morning -6-watt's draw per hour of operation
-High pressure water pump for the cabin water system for the shower and sink and washing machine .8.8.amps draw per hour of operation
-24.inch flat screen lcd color tv.3.amps draw
-dvd player for the tv .2.8.amps draw
-Air ventiltion system -24-hour is 15 watt's per hour of operation and it will run about 12 to 18 hour's a day in a cycling as it need


No i can not use propane or LG gas because of the way the house is buried into the side of the hill and i do not want to have to do some extras venting as it is .The plan is to use the earth cover to keep it cool in the summer and warm in the winter and nothing else .The whole thing is going to be buried under 14.ft of earth with a complete U shaped french drain system with a side entance into the house .

The unit is going to be completely buried like the dome in Texas and using the Fulcum sun light for basic use when inside the place to read as it need and the led light's are in the bathroom-kitchen -storage area's etc .

The rest of the items are used as it need in the place with the three main unit's are used for cooking my meals as it need .I'm going to have a outside propane grill for grilling up food as i need

I'm do not know the ipad and cell watt draw for charging there battie items .

Comments

  • icarusicarus Posts: 5,108Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    I know y are not keen on propane,, but perhaps you could consider an out door water heater ( demand type peferably). Is sounds like you are going to have propane outside for cooking.

    You are asking a lot of a battery based system.

    As has been suggests so often on this forum,, it is not the size ofloads that matter as much as the size of the loads, couple with their DURATION! A 100 watt load for 1 hour is not the problem that that same 100 watt load would be for 24 hours!

    Tony

    PS. You should be clear that power is measured in amp/hours, or watt/ hours, not watts per hour. So for example, a 100 watt light bulb, burning for 1 hour will consume 100 watt HOURS!

    Until you do a good estimate as to the loads, AND THIER DURATION you will have little idea of your true power needs.
  • CariboocootCariboocoot Posts: 17,615Banned ✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    To expand on what Tony said; don't expect any of these things to use the amount of power stated in the manufacturers' specifications.

    For instance a "600 Watt" microwave. Usually that's the cooking power, not the power consumption. I have one at the cabin and it actually uses 1000+ Watts (varies a bit). If you use that for 2 minutes that is 34 Watt hours.

    An 1800 Watt cook top, induction or not, if used for 10 minutes is 300 Watt hours.

    You can get ugly surprises this way too. If you have a desktop computer that draws "only" 150 Watts but you use it 8 hours a day it adds up to 1200 Watt hours - about the same as a standard refrigerator.

    Heating elements of any type draw big Amps even if for a short period of time. This means you need a large inverter to supply the over-all Watts plus a substantial battery bank to handle the current. The rest of the time all that big, expensive equipment is only having to provide 200 Watts or so.

    If you've already got any of these things you want to run, get a Kill-A-Watt and run them through that during "typical use" and see what kind of Watt hour numbers you actually come up with. Some will use less, others more. Very important to plan this out as accurately as possible. Much better to do that than to have the power go off at 1:00 A.M.!
  • offgridderoffgridder Posts: 25Registered Users ✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    I must agree with the other posts, you should consider using as many propane items as you can. We have been off grid for 2 years & still have much to learn. One thing I am VERY happy I did was indeed incorporate as many propane appliances as we could. We use propane for our fridge, heat (wood stove was out of the question as the size of our place is only 400 sqft - we tried it), on demand hot water heater & stove... This is a huge savings. If you need a microwave then remember the power usage labels do not equal actual everyday numbers, they are 100% correct in what the previous stated. Just saying, calculate & re-calculate & add to those numbers so you have your usages covered!

    Jonathan
  • icarusicarus Posts: 5,108Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    As a side note, I know you have stated that you don't wish to do propane because of the venting. I would posit that proper venting ( both of flue gasses and potential propane lek drain) would be way cheaper than going all electric.

    Most demand water heaters can be instlled with sealed combustion, such that they draw outside air, and directly vent flue gases. The idea of trying to power a bread machine, an induction cook top and an electric water heat off of batteries is a pretty big nut to crack.

    Let's just use the water heater as an example. 1650 watts of AC. Convert that from DC and with inverter loses let's say it's total draw is 2000 watts. That is over 150 amps from 12 vdc, or 75 from 24. Even the largest battery is going to have trouble delivering that load for very long, now let's further assume that it will run 4 hours a day. (thee are ~3300 BTUs in kwh, It takes about 600 BTUs to raise water 60F) so assume that you wish to raise ten gallons per day (5 for shower, 5 for other stuff) that would be over 2 kwh of power.

    Using my quick 50%*4 rule, you would need 1000 watts of PC, (along with the batteries just for the water heater. Add in the rest of your loads, and you could easily need a system in the 5-10 kw range. At $8 per watt inclusive, that could be $40,000-80,000 to do what you are talking about.

    As we often say,, conservation first, follows by more conservation, and then some more. We also say that every dollar spent on conservation saves five to ten in PV
    costs.

    By the way, my 50%*4 rule is this. Take the name plate rating of the PV, divide it in half to account for all cumulative system loses, then multiply that number by four to represent the average number of hours of good sun one can reasonably expect, per day, averaged over the course of the year.

    The biggest mistake beginners make is over estimating the amount of sun they actually get, while at the same time underestimating system efficiency, and underestimating loads.

    Tony

    Ps. FYI, we live off grid, with 400 watts of PV, into 450 ah of battery. On the average day we consume ~500-800 WH (.8 kwh) and we generally replace that on a daily basis. Nearly perfect 50%*4! That said, the system, on an ideal day can produce upwards of 2 KWHs, but we can't count on that.
  • waynefromnscanadawaynefromnscanada Posts: 3,009Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    And you will learn not to be too reluctant to make use of ventilation. Doesn't take long ( a very few hours) for pollutants to build up inside and you end up not feeling well, coughing etc. If you haven't got your health, all is for nothing. Air to air heat recovery ventilators work very well. Beyond that, I agree with the others here, you're asking a heck of a lot for an off grid system. I hope you have very deep pockets. And you might also consider solar hot water. I haven't been out of hot water since Spring, and haven't paid one cent for the energy to heat it.
  • icarusicarus Posts: 5,108Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    Wayne,

    Thanks for mentioning hot water,,

    If you can use PV, you are crzy not to use solr hot water. It is mu ch more forgiving of partial shading, costs way less per btu than PV, and is many times more efficient in converting solar energy into usable energy.

    Tony
  • solar_davesolar_dave Posts: 2,337Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin
    icarus wrote: »
    Wayne,

    Thanks for mentioning hot water,,

    If you can use PV, you are crzy not to use solr hot water. It is mu ch more forgiving of partial shading, costs way less per btu than PV, and is many times more efficient in converting solar energy into usable energy.

    Tony

    And you size it to carry enough storage for a few days easily, that plus a propane instant hot water system you will never want for hot water and your propane usage will be minimal.

    I know I have a nat gas setup similar to that and the worst month out of the year uses 4 therms of gas on a 2500 Sq ft house with 2 grand kids (the weasels) taking looooong showers and baths.
  • henry1henry1 Posts: 51Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin
    To expand on what Tony said; don't expect any of these things to use the amount of power stated in the manufacturers' specifications.

    For instance a "600 Watt" microwave. Usually that's the cooking power, not the power consumption. I have one at the cabin and it actually uses 1000+ Watts (varies a bit). If you use that for 2 minutes that is 34 Watt hours.

    An 1800 Watt cook top, induction or not, if used for 10 minutes is 300 Watt hours.

    You can get ugly surprises this way too. If you have a desktop computer that draws "only" 150 Watts but you use it 8 hours a day it adds up to 1200 Watt hours - about the same as a standard refrigerator.

    Heating elements of any type draw big Amps even if for a short period of time. This means you need a large inverter to supply the over-all Watts plus a substantial battery bank to handle the current. The rest of the time all that big, expensive equipment is only having to provide 200 Watts or so.

    If you've already got any of these things you want to run, get a Kill-A-Watt and run them through that during "typical use" and see what kind of Watt hour numbers you actually come up with. Some will use less, others more. Very important to plan this out as accurately as possible. Much better to do that than to have the power go off at 1:00 A.M.!
    icarus wrote: »
    As a side note, I know you have stated that you don't wish to do propane because of the venting. I would posit that proper venting ( both of flue gasses and potential propane lek drain) would be way cheaper than going all electric.

    Most demand water heaters can be instlled with sealed combustion, such that they draw outside air, and directly vent flue gases. The idea of trying to power a bread machine, an induction cook top and an electric water heat off of batteries is a pretty big nut to crack.

    Let's just use the water heater as an example. 1650 watts of AC. Convert that from DC and with inverter loses let's say it's total draw is 2000 watts. That is over 150 amps from 12 vdc, or 75 from 24. Even the largest battery is going to have trouble delivering that load for very long, now let's further assume that it will run 4 hours a day. (thee are ~3300 BTUs in kwh, It takes about 600 BTUs to raise water 60F) so assume that you wish to raise ten gallons per day (5 for shower, 5 for other stuff) that would be over 2 kwh of power.

    Using my quick 50%*4 rule, you would need 1000 watts of PC, (along with the batteries just for the water heater. Add in the rest of your loads, and you could easily need a system in the 5-10 kw range. At $8 per watt inclusive, that could be $40,000-80,000 to do what you are talking about.

    As we often say,, conservation first, follows by more conservation, and then some more. We also say that every dollar spent on conservation saves five to ten in PV
    costs.

    By the way, my 50%*4 rule is this. Take the name plate rating of the PV, divide it in half to account for all cumulative system loses, then multiply that number by four to represent the average number of hours of good sun one can reasonably expect, per day, averaged over the course of the year.

    The biggest mistake beginners make is over estimating the amount of sun they actually get, while at the same time underestimating system efficiency, and underestimating loads.

    Tony

    Ps. FYI, we live off grid, with 400 watts of PV, into 450 ah of battery. On the average day we consume ~500-800 WH (.8 kwh) and we generally replace that on a daily basis. Nearly perfect 50%*4! That said, the system, on an ideal day can produce upwards of 2 KWHs, but we can't count on that.



    I use a Apple Ipad for main computer device in my place .I did away with the computer totaly to save wattage and the ipad does everything i need i for

    The venting system is design that hot air to rise up and out of a roof top venting system and he cooler air is drawn in from the bottom and it moved through the place through a simple 12.volt ceiling fan system ..

    The unit living space is only about 350.square foot total or 22.ft long-x-14.ft wide-x-10.ft tall

    That the reason for the Honda generator unit for those days that the solar and wind does produce the wattage need to recharge the battery

    My daily cooking total time is about three 20 min's to 30 mins max time frame plus the bread machine is use one a week twice during the weekly bread baking .

    the once a week washing of laundry is about four hours a week with two loads a week with the laundry is hung outside when it nice and when it not the combo dryer is used .
  • henry1henry1 Posts: 51Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    Here is a floor plan layout of the place. the bed is a full sized unit and the living room set up is design for a single person not a family
  • VicVic Posts: 2,906Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    Regarding Propane, I've kinna gone the other way. A few years ago, when LPG was pushing through $2.75/Gal delivered, added some additional panels, and told the LPG supplier that until the brought the price DOWN, I'd need almost NO additional deliveries.

    Still waiting, have heard that LPG is now around $3.50/G delivered. It is very convenient stuff, and great for cooking, and space heating, but, for now, it is used for cooking only.

    The current generation of EnergyStar Refers are very miserly on Kwh consumed, and a perfectly serviceable one is about 25% the cost of an LPG refer. They do require a bit of an inverter to start them well, but well worth it ... interior light(s), auto defrost etc.

    Good Luck with the neat new cabin, henry1. Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2[email protected], 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • offgridderoffgridder Posts: 25Registered Users ✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    Another question is where are you located? How much sun are you getting daily?
  • henry1henry1 Posts: 51Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    Up in the white mountain's of Az i have about three acre's of land there .the basic plan is make into a off grid retirment home.
  • CariboocootCariboocoot Posts: 17,615Banned ✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    Speaking as someone who has done and (regrettably) continues to do a lot of work on houses, may I offer some suggestions on the plan?

    For a semi-submerged design, square may work better than rectangular. You get a better volume-to-surface-area ratio. If you put it on the diagonal you can get a lot of light inside from two exposed walls (if this is in keeping with your plan).

    The kitchen appliance layout should be in a "work triangle". I know that sounds trite but both the Mrs. & I put in our kitchen hours and the 'frige-to-stove-to-sink plan makes the work faster. The old house I reworked along those lines with an island in the middle. Relatively small kitchen (about 12 x 12, which may sound huge to some people) but it was very easy to get full-family holiday meals prepared with both of us working in there at the same time. Even for daily dining it was better.

    Looks like you're doing a divided bath. Usually that's done with the tub/shower separated and the sink & toilet together. You seem to have isolated the sink (some homes in Europe have the sink in the bedroom).

    Not criticizing; just want to be sure you look at lots of options before you pour the concrete. I've changed enough of them afterward to know that's not the easy time to do it! :p
  • samuelsamuel Posts: 80Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    I second what Cariboocoot pointed out. Not all appliances use what you would think for power. An Emerson 700W cooking power microwave will use 1135-1150 watts while in use as measured by a Kill-a-Watt meter. Light bulbs also vary. It's not uncommon for the bulbs to use more than they claim, especially when they are advertised as energy efficient CFLs. I've tested 23W CFLs and they regularly run at 24.5W (not really too significant, but it shows that advertising can be misleading on some products).

    If LP is feasible beware gas ranges/stoves. Electronic ignition can be great for the burners, but for the oven some models have a "glow type ignition" thingy that basically sucks up 400W for a few minutes after the oven reignites (I suppose it stays on for a while as some sort of safety feature). Here is a Kill-a-Watt list of power use from when I surveyed my family's cabin.

    Also, regarding LED lights. I would consider 400 lumen a reasonably bright LED. I recently installed a 3x 5.6W LED fixture (1200 lumen total) and would judge it to be as bright as about 2 x 18W fluorescent recessed lights. LEDs are about 2x as efficient as fluorescent in output. Of course, individual results may vary. Here is 4.5W LED / 330 lumens of bright white light (6500K) for reference. It is enough to get around but if you were in a kitchen trying to cook at night 800 to 1200 lumen will be adequate.

    mg_35311.jpeg

    Also helpful when shopping for LED's is this color chart:
  • henry1henry1 Posts: 51Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin
    samuel wrote: »
    I second what Cariboocoot pointed out. Not all appliances use what you would think for power. An Emerson 700W cooking power microwave will use 1135-1150 watts while in use as measured by a Kill-a-Watt meter. Light bulbs also vary. It's not uncommon for the bulbs to use more than they claim, especially when they are advertised as energy efficient CFLs. I've tested 23W CFLs and they regularly run at 24.5W (not really too significant, but it shows that advertising can be misleading on some products).

    If LP is feasible beware gas ranges/stoves. Electronic ignition can be great for the burners, but for the oven some models have a "glow type ignition" thingy that basically sucks up 400W for a few minutes after the oven reignites (I suppose it stays on for a while as some sort of safety feature). Here is a Kill-a-Watt list of power use from when I surveyed my family's cabin.

    Also, regarding LED lights. I would consider 400 lumen a reasonably bright LED. I recently installed a 3x 5.6W LED fixture (1200 lumen total) and would judge it to be as bright as about 2 x 18W fluorescent recessed lights. LEDs are about 2x as efficient as fluorescent in output. Of course, individual results may vary. Here is 4.5W LED / 330 lumens of bright white light (6500K) for reference. It is enough to get around but if you were in a kitchen trying to cook at night 800 to 1200 lumen will be adequate.

    mg_35311.jpeg

    Also helpful when shopping for LED's is this color chart:


    Thank's for the info on the diff lighting items .Yes i ran a kill a watt on most of the items i bought for the place to see what they where going to cost me daily in wattage draw from the battie bank

    Speaking as someone who has done and (regrettably) continues to do a lot of work on houses, may I offer some suggestions on the plan?

    For a semi-submerged design, square may work better than rectangular. You get a better volume-to-surface-area ratio. If you put it on the diagonal you can get a lot of light inside from two exposed walls (if this is in keeping with your plan).

    The kitchen appliance layout should be in a "work triangle". I know that sounds trite but both the Mrs. & I put in our kitchen hours and the 'frige-to-stove-to-sink plan makes the work faster. The old house I reworked along those lines with an island in the middle. Relatively small kitchen (about 12 x 12, which may sound huge to some people) but it was very easy to get full-family holiday meals prepared with both of us working in there at the same time. Even for daily dining it was better.

    Looks like you're doing a divided bath. Usually that's done with the tub/shower separated and the sink & toilet together. You seem to have isolated the sink (some homes in Europe have the sink in the bedroom).

    Not criticizing; just want to be sure you look at lots of options before you pour the concrete. I've changed enough of them afterward to know that's not the easy time to do it! :p

    The kitchen area is a basic U shaped set up with it design that i never have to walk more than three step's to something inside the kitchen .The socalled mock up does not do it justice and when i can i try to shoot some picture's of the place .


    Thank you again for the info on the place
  • henry1henry1 Posts: 51Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    I know that sound's stange to some folk's but for years i have worked from 6.pm in the evening to 4.am in the morning in a 4 day work week and never really felt the need for a cable or sat tv package in my place .My internet was through the usb wireless broadband card to get on the internet and surf and shop and answer email's as it need on my old laptop and now i use the ipad to do the same thing .

    The work shift started at 6.30.pm and ended at 3.30.am with a 30 min drive each way to and from work .So i would leave the house at 5.30.everday i worked to get there before 6.15.to start the shift and once i left from work i would stop in a local walmart to shop on the way home or go to someplace for supper before going home .So i got out of watching prime time tv habit and went to watching movies and tv series i like on my day off's

    So when i move up there full time i'm just going with the ipad as my main computer type device and nothing else and watching movie's when i want to on the 12.volt powered tv .
  • jalbersjalbers Posts: 13Registered Users
    Re: The cabin Appliance's list so far to run off a off gid cabin

    I guess I'm just amazed at some of the replies here. I have been off grid in Arizona, full time, for 12 years now. Why one would want to use propane when you have solar electric available, is beyond me. You are trying to build a place that is SOLAR POWERED. I say....use that power. Why burn fossil fuels when you have power from the sun? We do not have (and don't need) a generator. All pumps are solar. The water is heated by solar panels. In our case (we have a large system) we even have solar air conditioning and heat!

    Keep it simple, but use as much solar as you can. That's what it's all about!!!!

    Jerry
  • CariboocootCariboocoot Posts: 17,615Banned ✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin
    jalbers wrote: »
    I guess I'm just amazed at some of the replies here. I have been off grid in Arizona, full time, for 12 years now. Why one would want to use propane when you have solar electric available, is beyond me. You are trying to build a place that is SOLAR POWERED. I say....use that power. Why burn fossil fuels when you have power from the sun? We do not have (and don't need) a generator. All pumps are solar. The water is heated by solar panels. In our case (we have a large system) we even have solar air conditioning and heat!

    Keep it simple, but use as much solar as you can. That's what it's all about!!!!

    Jerry

    Not everyone lives in AZ.
    Electricity is an incredibly inefficient way to heat things.
    Not everyone has huge amounts of money to invest in solar; propane is a far cheaper source of heat in most areas.

    We try to be practical about things around here. You won't see anyone advocating that everyone must go 100% solar right now the way the psychotic "green" sites do because it simply is not a sensible course to follow.
  • icarusicarus Posts: 5,108Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin

    Jerry

    You mentioned solar hot water,bu t the OP was talking about PV water heat, a different nut entirely. As coot says, not everyone live is AZ, and perhaps doesn't have the kind of deep pockets required to be battery based off grid to run things like resistance electric heat off of batteries.

    Tony
  • jalbersjalbers Posts: 13Registered Users
    Re: The cabin Appliance's list so far to run off a off gid cabin

    Yes and no guys. I darn sure do not have deep pockets. Over the years our system has grown. I have 30-75 watt panels and 16 L-16 batteries. AZ is a bad place to live in the summer. Your panels and batteries loose a lot in the heat. I live in the mountains of Northern AZ. With a wood stove and the "electric" heat, the house stays very nice in the winter. My only point was if you have solar, use it as much as you can. IMHO

    Jerry
  • BB.BB. Posts: 27,681Super Moderators admin
    Re: The cabin Appliance's list so far to run off a off gid cabin

    Just to be clear, it is not that we don't want to help with designing a system to power an all electric home--We just want to stress conservation/alternative heating sources that may (or may not) make sense.

    When it comes down to designing the system, once we know the number of kWH per day/month needed, we can plug in some design numbers.

    Using PV Watts, Albuquerque New Mexico (closer to your weather? or would someplace in central AZ be better?), and 1kW fixed array with 52% end to end efficiency:
    "Station Identification"
    "City:","Albuquerque"
    "State:","New_Mexico"
    "Lat (deg N):", 35.05
    "Long (deg W):", 106.62
    "Elev (m): ", 1619
    "PV System Specifications"
    "DC Rating:"," 1.0 kW"
    "DC to AC Derate Factor:"," 0.520"
    "AC Rating:"," 0.5 kW"
    "Array Type: Fixed Tilt"
    "Array Tilt:"," 35.0"
    "Array Azimuth:","180.0"

    "Energy Specifications"
    "Cost of Electricity:"," 8.7 cents/kWh"

    "Results"
    "Month", "Solar Radiation (kWh/m^2/day)", "AC Energy (kWh)", "Energy Value ($)"
    1, 5.33, 84, 7.31
    2, 6.06, 84, 7.31
    3, 6.44, 99, 8.61
    4, 7.16, 102, 8.87
    5, 7.40, 105, 9.13
    6, 7.10, 95, 8.26
    7, 7.13, 98, 8.53
    8, 7.02, 98, 8.53
    9, 6.71, 91, 7.92
    10, 6.55, 97, 8.44
    11, 5.73, 85, 7.39
    12, 5.14, 81, 7.05
    "Year", 6.48, 1119, 97.35

    You are looking at 81-105 kWH per month per 1kW of solar panels...

    If you want 300 kWH per month -- You will need 3-4x 1kW or ~3-4kW of solar panels.

    For a 1kW array that outputs ~105kW per month in May, or:
    • 105kW per May / 31 days per month = 3.39 kWH per day = 3,390 WH per day
    Battery, assuming 85% Inverter efficiency, 2 days of "no sun", 50% maximum discharge (for longer life), and a 48 volt battery bank, per 1kW array:
    • 3,390 WH * 1/0.85 invtr eff * 2 days no sun * 1/0.50 max discharge * 1/48 volt battery bank = 332 AH @ 48 volts per 1kW of solar panels
    So--now you have some rough (and hopefully conservative) estimates for the amount of solar panels and battery bank sizing per ~81-105 kWH per month of power.

    So, all we need to do is add up your summer and winter estimated electrical loads (using a Sanyo or equivalent mini-split with heat pump and a solar thermal array for hot water/space heating -- as makes sense to the original poster).

    -Bill

    PS: Here is the same 1kW array for Prescott AZ:
    "Station Identification"
    "City:","Prescott"
    "State:","Arizona"
    "Lat (deg N):", 34.65
    "Long (deg W):", 112.43
    "Elev (m): ", 1531
    "PV System Specifications"
    "DC Rating:"," 1.0 kW"
    "DC to AC Derate Factor:"," 0.520"
    "AC Rating:"," 0.5 kW"
    "Array Type: Fixed Tilt"
    "Array Tilt:"," 34.7"
    "Array Azimuth:","180.0"

    "Energy Specifications"
    "Cost of Electricity:"," 8.5 cents/kWh"

    "Results"
    "Month", "Solar Radiation (kWh/m^2/day)", "AC Energy (kWh)", "Energy Value ($)"
    1, 5.28, 82, 6.97
    2, 5.71, 81, 6.88
    3, 6.15, 94, 7.99
    4, 6.78, 98, 8.33
    5, 7.06, 104, 8.84
    6, 7.07, 96, 8.16
    7, 6.33, 87, 7.40
    8, 6.51, 91, 7.74
    9, 6.59, 91, 7.74
    10, 6.52, 95, 8.07
    11, 5.58, 82, 6.97
    12, 4.99, 77, 6.54
    "Year", 6.22, 1079, 91.72

    Perhaps 10% less solar power / sun for that location...
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • henry1henry1 Posts: 51Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin
    BB. wrote: »
    Just to be clear, it is not that we don't want to help with designing a system to power an all electric home--We just want to stress conservation/alternative heating sources that may (or may not) make sense.

    When it comes down to designing the system, once we know the number of kWH per day/month needed, we can plug in some design numbers.

    Using PV Watts, Albuquerque New Mexico (closer to your weather? or would someplace in central AZ be better?), and 1kW fixed array with 52% end to end efficiency:



    You are looking at 81-105 kWH per month per 1kW of solar panels...

    If you want 300 kWH per month -- You will need 3-4x 1kW or ~3-4kW of solar panels.

    For a 1kW array that outputs ~105kW per month in May, or:
    • 105kW per May / 31 days per month = 3.39 kWH per day = 3,390 WH per day
    Battery, assuming 85% Inverter efficiency, 2 days of "no sun", 50% maximum discharge (for longer life), and a 48 volt battery bank, per 1kW array:
    • 3,390 WH * 1/0.85 invtr eff * 2 days no sun * 1/0.50 max discharge * 1/48 volt battery bank = 332 AH @ 48 volts per 1kW of solar panels
    So--now you have some rough (and hopefully conservative) estimates for the amount of solar panels and battery bank sizing per ~81-105 kWH per month of power.

    So, all we need to do is add up your summer and winter estimated electrical loads (using a Sanyo or equivalent mini-split with heat pump and a solar thermal array for hot water/space heating -- as makes sense to the original poster).

    -Bill

    PS: Here is the same 1kW array for Prescott AZ:



    Perhaps 10% less solar power / sun for that location...

    The main reason why i went with earth covering of the place so not to have to worry about any future heating or cooling bills once i retired along with the way the price of fuel keeps going i know that the way i bult the place that way in the first place .

    You pretty dead on about the solar number's for the area and that why i chose a small honda generator to help with those days when the sun did not come out or a storm has passed through the area

    My basic goal is keep my power need's about te 2.kw area for every day use total in the place and that way i have did away with alot of the socalled extras like sat tv and other thing's that eat's power from a battery bank set up .So it been streamline down to the basic thing's i could not live without and that the list i posted here .

    I do have a small marine style propane power grill that use 1pd sized propane canstiers unit to cook with and i'm storing my frozen items and meat from grocery store in a engel 80.qt freezer i'm going to add to the list next month .

    I bought a brand new model from a local place down in Phx area and it going to be pluged into the system here in the end of dec once everything is ready to go .

    My home is allmost bult and ready to be lived in right now and i need to make a few more dollar's before i finish it up with the solar system i have planned to build and my budget for it about $45,000.oo dollar's wit top of the line items to make my own power there . .

    The figure is for the basic fact that i know that they are going to over run's on the project allong with having some basic problems where thing's did not go as plan .So it better to plan for a bigger budget than plan for a smaller one and have to draw money out from the saving to cover it .
  • henry1henry1 Posts: 51Solar Expert ✭✭✭✭
    Re: The cabin Appliance's list so far to run off a off gid cabin
    icarus wrote: »
    Jerry

    You mentioned solar hot water,bu t the OP was talking about PV water heat, a different nut entirely. As coot says, not everyone live is AZ, and perhaps doesn't have the kind of deep pockets required to be battery based off grid to run things like resistance electric heat off of batteries.

    Tony

    I have six 100.ft long garden hose that is kept in a coiled prostion inside one plastic 10.gallon drum that has been painted black to heat it up with on each side of the drum are four black painted pvc pipe's 10.ft long lengths connected togerther with hose threaded through them in a u-shaped set up to help heat the water coming into and out of the drums . With each hose connected to each other and have connections that goes to the side of the drum & pipe'sto connect to the main incoming and outgoing hose system from the house

    The pipes are design to be disconnected as it need from the side of the drum through a simple screw in out thread system with the hose is kept in the two pipe's coming into the unit to help pre-heat the water and help keep the water hot as it passed though the system into the house to be used .the end of the pipe has the standard hose connection to allow me to connect the hose to the unit and pump water into or out of the system

    The water is pumped into the drum in the early morning hour's and allowed to heat up as it need during the day time when it hot outside during the summer month's where i can get the heat from the sun to heat the water .

    The drums and pvc piping basically heat's the water up twice a day .Once in the morning when i take a shower and once in the evening when i do the dish and take a quick shower before bed .the water is basic handed pumped into the unit's then allowed to sit and get hot and when it need it i use a simple 12.volt powered water pump to pump the water into the place .

    the unit is design to be broken down and stored as it need during the winter month's because of the area where i'm at can and has gotten down to 20 above zero .so it design to set up and broken down as it need and stored ready to go when the weather turn's warm again and it broken out as it need

    The whole thing can be bult for less than $100.oo total with the part's coming from a large box store and the labor is pretty easy to do even for a non skilled person like me to build .

    I got the idea from mother earth news issuse about building a protable solar water heater for a travel trailer and just did a basic rework of the system

    During the winter time the small hot water heater will be the used as the primary heating of the water in the place .
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