Discussion in 'General Electronics Discussion' started by [email protected], Oct 8, 2012.

1. ### [email protected]

24
0
Mar 26, 2012
Dear SIR
I have a 12v, 20 Ah DC load and i want to purchase a solar panel to run this load. Please guide me how much watts of solar panel are required to run this load

Last edited by a moderator: Oct 8, 2012

1,301
57
Feb 26, 2011
3. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,505
2,852
Jan 21, 2010
That will get it running while the sun shines 100% on the panels -- which is pretty much never. (and assuming that 20aH means 20A).

You need to determine the number of hours of equivalent full sun you get in the worst part of the year. Here I get about 6 hours in winter. Then you need to allow for battery inefficiencies, and then for extra capacity to allow for rainy days.

So a rough guess for me would be 240 * 24/6 * 2 - 1920W -- I'd probably go for around 2400W of panels. -- then you have to think about the battery capacity.

4. ### [email protected]

24
0
Mar 26, 2012
Plz help

I have FIVE 12v 2ah DC fans and five lights of same capasity
whom i want to run and also a battry of 60ah to b charged simultanously.
now how many watts of pannel are required???????????????????????????

5. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,505
2,852
Jan 21, 2010
Fans are not rated in Ah.

Garbage-in/Garbage-out.

Until we know what the rating o the fans is, I can't give you any more information.

6. ### [email protected]

24
0
Mar 26, 2012
I have already replied that fan are of 2Ah

7. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,505
2,852
Jan 21, 2010
Look for something like 2A, 200mA 0.2A, or anything that specifies a current.

OR

2W, 6W, 0.5W -- A wattage os OK too.

Failing that, post a picture of the fan with the markings clearly visible.

Also, do you want them on 24x7? How many cloudy days do you want to tolerate? How fast do you want to charge the battery?

If you want details, then we need details too.

8. ### [email protected]

24
0
Mar 26, 2012
Thanks

Dear Sir i appriciate ur's guiedence and efforts

Sir here it is sunny day approximately 10 months 1 month is cloudy and 1 is hazy and i need solar energy to run my system in day hours and only a backup of 60AH now tell me what is the solution

9. ### BobK

7,682
1,689
Jan 5, 2010
You know, if you would answer ALL the questions, it would help.

Bob

10. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,505
2,852
Jan 21, 2010
I can't tell you until I know what power the fans require (and that's NOT "ah") and how quickly you want to charge the battery.

I also don't know if "day hours" mean you only want to operate the fans when the sun is shining brightly (say for 6 hours a day), or for an extended period (sunrise to sunset)

If you can tell me your latitude I can figure out a little more.