Making 1180 Watt Solar Power System

guyzz... Recently i purchased Many Solar Panels.. :-)And the Details Of Solar Panels are:-

1. I have 45 Panels of 18 Watt
2. " " 10 Panels of 37 Watt

And i am putting 20 Lead Acid Battries with 3KW UPS made by FISKERS and (2) UPS from APC about 1KW Each so the Total power i get is 5Kw...And i Get Aprrox 6 to 7 Hours Sunlight Per Day.
So the Items i am going to use Are :

1. 2 COLOR TV Around 120 Watt 4 Hours Max 6 Hours
2. 5 Fans 350 Watt 4 Hours Max 7 Hours
3. 5 Lights 300 Watt 4 Hours Max 5 Hours
4. 3 Desktop Computers 500 Watt 11Hours Max 18Hours Only 1 PC
5. 2 Fridge 1500 watt 24Hours But Let Compressor on for only 5 Hours a Day Max (After Opning 100 Times)

Almost 85% of Home i am going to Run From Solar!!!!!!!!

So Guyz wat u Sayy!!!!!! :mrgreen:


  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Making 1180 Watt Solar Power System

    i think it is highly questionable if the pvs you have will run all of that every day. i also question the wattage figures you've come up with for each item. would it work? i don't know as it does depend on the real draw and the location you are in with the time of the year as a big variable many forget about. even your batteries i question as it depends on their ah capacity to judge even if this is sufficient.
    do note that one hour of sun to a pv is at the intensity rating of 1000w per meter squared. it may be bright and sunny, but not at the intensity to rate it at a full sun hour. for instance, 4 hours of a 250w intensity gives 1 full sun hour.
    also be advised that duplicate posts are unnecessary as it will be answered with one posting if it is answerable. i have deleted your duplicate posting.
  • BB.BB. Super Moderators, Administrators Posts: 33,085 admin
    Re: Making 1180 Watt Solar Power System

    Need to know, approximately in what part of the world you are located (near major city)...

    Adding up your power (I am guessing that some of the numbers are wrong--2x120=240 watts for the TV looks fine, but 5x300=1,500 watt for lights look high):

    2x120x4=960 watthours per day
    5x350x4=7,000 wh/d
    5x300x4=6,000 wh/d
    3x500x11=16,500 wh/d
    2x1500 (per day?)=3,000 wh/d
    33,460 wh/d or 33.5 kWhrs per day... 1,000 kWhrs per month...

    My (near SF CA) grid tied system, not optimally aligned to the sun (little bit of morning evening shading--call it 5-6 hours of good sun per day) 3,500 watts Peak generates about 15 kWhrs per day from April through September (including cloudy weather, etc.).

    You panels add up to:

    45*18 + 10*37 = 1.18 kW peak...

    Even if you were able to double my systems ability to gather sun (very possible)--you probably are only 1/3 of the way to powering "everything"...

    Plus, once you add inverters and batteries--you are now down to:

    ~80% (lead acid battery charge efficiency) * 80% Inverter eff = ~64% efficiency overall...

    Meaning that you need to increase you solar panels by 1/64% by 1.56x more to make up for your losses.

    If you live in an area that allows grid tied solar (with reasonable terms), going Grid Tie costs less and is, overall, more efficient that going through the battery route.

    If you need batteries (no grid tie or want back up power), then you have to live with the losses.

    In the end, conservation of energy is always cheaper and recommended before trying to throw solar at the problem (change lites to CPFL and/or florescent, energy efficient appliances, using laptop computers instead of desktop computers, turn off everything using power strips to save standby power--cell phone chargers, microwave ovens, TVs, satellite boxes, etc...

    It is always difficult to give suggestions to somebody unknown living in an unknown state/country, with unknown weather and energy requirements. But I found it nice to have a goal for energy savings. It does not have to ever be achieved--but it helps to keep one focused on a goal.

    For example, I used 100 kWhrs per month as my goal. That is a 24 hour per day load of 139 watts. All of a sudden, the 8 watts that my washer and drier spend on standby ended up almost doubling their total energy use over a one year period.

    That laptop computer that takes about 20-30 watts all of a sudden looks much better compared with that desktop system at 120-500 watts running completely blew my entire power budget.

    I was (a family of four) was never able to hit 100 kWhrs per month--but I did get down to a few months of 175-185 kWhr a month during the summer (this is in a US house hold with central heat, washer, drier, 2 computers, network, UPS, several TVs, digital receiver, large fridge, two laser printers, kids who don't turn off lights, etc.).

    You did not give the actual "ampacity" of your batteries--but a good start is to size the system to store 3 days of energy down to a depth of charge of 50%... So:

    33,500 Whrs * 3 Days * 1/50% battery discharge / 12 vdc battery bank = 16,750 amp*hours (at 12 volts)

    If you have a 24 volt battery system (higher voltage is recommended--48 vdc charger/inverter would work well too), that would be 16,750 / 24 = 8,375 A*H at 24 vdc

    Those are not small battery banks... In general, it is not that difficult to build a system that will power, for example, a 1 kW microwave for 10 minutes per day--but building something that will supply (33.5kWhr/day / 24hours=)1.4 kW 24 hours per day for 3 days is something else.

    Did any of this help?

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • RoderickRoderick Solar Expert Posts: 253 ✭✭
    Re: Making 1180 Watt Solar Power System

    Sounds like a nice start.

    Do you know how you plan to charge the batteries in the UPS? Is some other charging circuitry involved? Or is there some input already suitable for solar?

    I think you may find that the lights, TV, and computer can use less power than budgeted. If you have other power coming into the house, then the worst that can happen is you end up not running as many things as you thought from solar. Even so, it's still an exciting prospect!

    6-7 hours of sun is very good. Where are you located?
  • BB.BB. Super Moderators, Administrators Posts: 33,085 admin
    Re: Making 1180 Watt Solar Power System

    Forgot to add... The Kill-A-Watt meter is probably the single cheapest and best meter for measuring power usage on your appliances (only works on 120VAC at 60 Hz--US style 3-prong plug).

    Looking at appliance name plates is not the best for estimating true day to day power usage.

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2System2 Posts: 6,290 admin
    Re: Making 1180 Watt Solar Power System

    Some questions about the panels - - what voltage are they? All 12 volt? And, what is their open circuit voltage? Were they sold as "not requiring a regulator"?

  • System2System2 Posts: 6,290 admin
    Re: Making 1180 Watt Solar Power System

    Hi SO I Am from INDIA (NEW DELHI ) and i am not using any other power resources expict SOLAR PANELS and soon i am Sending some photos and Few Video Clips and other Questions please fell free Bub bye :-)
  • System2System2 Posts: 6,290 admin
    Re: Making 1180 Watt Solar Power System

    OK SO Let me Explain U some things

    1. 3Kw Friskars UPS Runs on 48 Volts DC
    2. 1Kw APC " " " 24 Volts DC
    3. 1Kw APC " " " 24 Volts DC

    Am i have All Panels of 12Volts Wich Usally Givs 17 to 18 Volts... :roll:
  • System2System2 Posts: 6,290 admin
    Re: Making 1180 Watt Solar Power System

    Needs to run those post thru the spell checker

  • System2System2 Posts: 6,290 admin
    Re: Making 1180 Watt Solar Power System

    uh.. that 500w usage of the computer needs some clarification (or replacement) as well. thats horrendous. its probably wrong unless you have a huge CRT , 500w stereo system and laser printers running at full blast as [art of the equation.

    What I did recently is buy a little usb to IDE adapter very cheap: can modiffy a regular cd/dvd drive to be an external usb. this way i plug it in when needed.
    instead of keeping my computers dvd burner powered all the time (when its n use maybe 1/2 a % of the time - if that)
    having done some measuring i am quite shocked how much extra power the dvd burner uses. even idle! did i post those numbers here at one point?
    i forget.
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