ATTENTION Solar Power Experts: What is the minimum solar wattage I will need...

Probably 10 minimum...3kw get rid of fluorescent and get led

It vague and Im not really sure you know what you are asking...

Running a stove alone off solar power is expensive due to it being quite demanding during heating up.

Anyway, it all depends on your particular load, and you should start this project by first looking into energy saving, ie, learn your electric appliances. Replace old and energy guzzling stuff etc.

Then do daily checks of your meter, write down how much electricity you use on a daily basis..

Change to LED lights. Gas oven if possible.

Rent or purchase a watt meter KILL A Watt is one that plugs in and calculates average wattage for 110v appliances

Then sit down and do some math

Figure out how much time you use each load

Calculate to KWH then to AH for battery bank sizing

Focus on paring down the load instead of purchasing large capacity

You will be amazed how quickly it will pay for itself if you begin conserving

As per your current requirements you need 3kw panel. Not more then that.

Get your old power bills and look at what your energy consumption has historically been.

Take the number of KWh's you consume per month and double that number. So, for example if you consumed 500 Kwh's on average, then you will need to plan your solar to produce 1000 kWh's per month.

Take that number and dived by 30 for days. So in our example, 33 kWh's per day is need.

Your shortest day depends on where you live and how much shade you get. For me, I'm in North Carolina with some trees a couple hundred feet from my panels. I measure the arc angle in the sky from east to west and that tells me the number of ours of production I have. For me, on Dec 22nd, my shortest production is 3.2 hours.

So, if that is similar for you, then you need to produce 33 kWh's in 3.2 hours, or about 10 kw. Most panels are rated at 220 watts, but with inverters your lucky to get 200 watts under ideal conditions. Count on getting 100 watts per panel for the best panels. So you'd need 100 panels to generate 33 kWh's on that shortest day.

Next issue, is battery capacity to store the energy in a way that it will be usable over the whole 24 hours. There's loss in the charge/invert process, about 10% and you should never discharge your batteries below 50%.

So, that means batteries should have 75 kWh's of capacity. (33 * 2 for 50% discharge then * 1.10 for the 10% loss on charge/invert.)

From there, you can then decide, how many days in a row you might want to operate without solar production. For me, I get ice/snow cover of my panels for several days every could of years. I decided I'd need 5 days of battery storage. So that ups our battery capacity to 5 * 75 kWh's or 375 kWh's.

Scale those calculations by your actual conditions:

1) Kwhs you use per month
2) View of the sky and therefore shortest day of the year

Oh, and did I mention that there is absolutely no ROI for this. Its very expensive, even with the tax credits and rebates. The only benefit is being off grid, controlling your own destiny. For me this justified the expense. I've got 220 panels, charge controllers to produce 400 amps at 240 volts from three massive battery banks. I also have a 16 kw generator that I can use to supplemental charge the batteries if things get to bad. I keep about 10 days of fuel on hand for the generator. I've got more than $300K in my system.

Transformer/power supply depends on peak amps needed. If you need a lot this can be quite expensive...

Battery depends on technology and how much you use and how much spare capacity you want. Some batteries last a lot longer if you dont deplete them completely every day, other tech it does not matter. Batteries in general needs to be replaced fairly often. But again, depends on tech. The best batteríes are really expensive, but can outlive you. "Cheap" batteries needs replacement every 5 years or so.

Solar panels are the least problematic part, since you can easily just keep adding them until you got enough.

And with more solar panels than you really need, and if you can run more energydemanding stuff during daytime, you might get by with very little for your needs during the hours the sun is not up..

So... its a vague question.

Great idea, I hadn't thought of using led lighting.

Using gas appliances had crossed my mind but I should have began by stating I'm looking into moving to northern Arizona and I'm concerned about running out of gas during the winter.

My current daily kWh usage is 83.91, about 2685 per month.

First, that's extremely high for your foot print. Air conditioning?

Second, if this is the real number, then take the number that I gave in my detailed post (a couple back) and multiply by 2.6 for your requirements --> 260 panels, 200 kWh's of battery capacity and you will need a charge/controller capable of putting out at least 7-10 kw (aka, 45 amps at 220 volts.)

Solar panels by themselves are cheap enough nowadays to be able to compete. Problem is everything else you need, in particular batteries, which really makes this a bad financial "investment".

imho you should start out trying to cut back your energy usage, and get an in-grid solar panel as a starting point.

in-grid systems pay off right away and you get an introduction to solar power as well as an insight into the limitations/costs of an off-grid system.

You are correct. The panel costs on my $300K system were roughly 75K. Everything else was labor, cables, racks, batteries, charge controllers, transmission lines, etc. etc. But batteries, good ones, were the biggest ticket item at well north of $150K.

As always, YMMV.

use 6 solar panels , Rotoverter "Kruten" system & led lights.

Last Edited by x ² on 03/19/2016 10:05 PM

You get ripped, buddy.

Lithium Iron cells now 40 cents per kilowatt hour. Panels 40 cents per kilowatt in bulk.

$5k panels and $5k batteries is more than any sane house could ever use.

I put my own solar on my house.

First of all it's not so much the size of the house it is more like finding appliances that run on less wattage i.e.

I purchased a micro-wave that requires 400-6-- watts not the regular 12 1400 watts,buy LED lights. I use electric throws vs full size electric blankets for keeping warm in the winter time. I bought a heat-a-lator that goes inside the fire place that has a solar powered blower that blows the heat into house from the fire place. I have a 220 volt Air-cond with heat pump but I do not use it very much. I bought a 5000 btu
air-cond at a garage sale and I use that on a small room if it gets really hot. I bake bread in an automatic bread maker that just requires that you dump a box of premix in a machine and dump in a cup of water and plug it into the solar.
I put separate 120 out let in for my solar so I am totally off the grid when I want to be. I have 5 D$ 400 amps deep cell batteries for days when there is little or not sun light. My outside automatic flood lights work from my solar because they are LED and require little power. I can cook meat on my electric frying pan that is low wattage. so Have you caught on yet. Get rid of all your high watt requirements and you only need about 1-3 Kw I use a little over 1 KW to do all the above

What about a washer/dryer?

Those take a lot of energy.

Fuck solar get diesel and some battery storage to soak up surplus generated.
Solar is stupid and complex, diesel is safe,easy and cheap relatively and foesnt require huge expense.
Get gas fridge andr wood heat and cook stoves

Diesel generators are cheap and reliable and easy to buy at any power level as surplus or used.
you could run them on grease you can buy decent used gendrators for u der 3 k that will run a whole house and just use relafively few batts for overnights with the genset off.

You will have to find the watts draw on the items you wish to hook to AC power inverters that run
off your solar grids batteries. Try to look for 300+ watt panels to keep the amount of them needed
down to a minimum.

The Canadian Solar CS6X-305M has great reviews and you should be able to get for just over
$200US per panel.

microwave (800 watts?)
stove/oven (use propane)
laptop (<100 watts)
refrigerator ( ? watts)
10+ fluorescent lights (go LED, 7 watts = 60 watt bulb)
TV (use LE D instead, <100 watts)
On demand water heater (use propane)
Fans (<100 watts each)

You can look here for an average wattage breakdown but depends on how old your items are also.
The newer refrigerators draw less watts then older versions also with the TV, use a LED unit.

[link to www.wholesalesolar.com]

Also here is a solar calculator that can come in handy once you have your total average wattage.

[link to www.wholesalesolar.com]

What clothes dryer?

get a small back up wind turbine as well