solar ac generator..

[shivam kumar chaudhary]

hi...i want to make a solar ac generator for CFL lighting (30 watts),table fan(25 watts)....i want to run them simultaneously...but i m unable to calculate the ratings of solar pannel,charge controller,inverter,battery to be used...will i have to use a step up transformer?....plz help me out with the required datas..

[Mike90250]

Do you need to run the appliances daytime, nighttime or both ? We need to know how many hours a day they will run.

That gives us a "watt hours used" and then we can figure how much to harvest and store.

Solar PV is DC, so if you need AC, and can't work with RV / Trucker 12V dc appliances, you will need an inverter to convert to AC. Motors and expensive electronics generally need Pure Sine wave inverters, otherwise, mod-square wave inverters can power heating type appliances - toasters, incandescent lamps....

[shivam kumar chaudhary]

solar ac generator

it will be used both for day and nigth...4-6 hrs without sunlight..can you please help with the ratings required for pannel,battery,charge controller,transformer,inverter....can you suggest me with a block/ciruit diagram of a ac solar generator?

[Sunking]

OK you stil have not quite gave us all the details, or at least they are fuzzy.

First let get your terminology on track. There is no such thing as a Solar AC Generator. What you are describing is an OFF GRID BATTERY SYSTEM using a stand alone inverter powered by batteries.

Need two things from you.

• The total amount of hours each item will be turned on in a 24 hour period. Not just night, both day and night.
• Your location.

For example if each item will be on for 6 hours per day then:
Number of CFL lights and their wattage, and how many hours. 1 fan at 25 watts x 6 hours.

So lets say you are looking at 3 30 watt CFL lights and 1 25 watt fan all running 6 hours per day:

3 x 30 watts x 6 hours = 540 watt hours.
25 watt fan x 6 hours = 150 watt hours
Total = 690 watt hours

Efficiency conversion adjustment = 2 x 690 watt hours = 1380 watt hours.

OK your solar panels need to generate 1380 watt hours per day. To determine what size of solar panel you need, you have to know your location and winter insolation in sun hours. So let's say you get 3 Sun Hours in winter. All we need to do is factor out the time element to get the panel wattage. w = wh / h = 1380 wh / 3 h = 460 watts.

For a 12 volt battery you need [5 x 1380 wh] / 12 volts = 575 amp hour battery.

For the charge controller I will assume a MPPT type so the minimum size is 460 watts / 12 volts = 38 amps.

The inverter with a low PF will be need twice the maximum connected load so you max connected load is 115 wats x 2 = 230 watts minimum inverter.

Now all we need is your real data, or you can do it yourself.

[Mike90250]

Nicely done, Sunking.

[russ]

Sunking the solar knight to the rescue!

As usual, Sunking provided an in depth reply with good information!

Russ

[shivam kumar chaudhary]

thanks sunking...

ya its very true RUSS "Sunking the solar knight to the rescue!"...
now,
i calculated all my datas..approx similar to your calculations sunking...
can you suggest me wit sum circuit or block diagram? i want to assemble it on my own..so what precautions should i take? should i use diode to stop backward flow of current from battery? should i use step-up transformer to get 220v? what about fuse or relays? please help me out...