Need help in calculation

[ulaw]

hello everybody, I'm new to this forum and I hope I can get some help. I live in the sunny Caribbean and we would like to have solar energy for our little house. our daily powerconsumption is around 5500Wh/day, but probably increasing in the near futur. can somebody tell me, how many panels we would need for that amount of watt/hour/day?
thank you, ursula

[freefuelforever]

Well, roughly you could figure out how many amp-hours you will use per day, then buy enough solar to trap that amount, less losses in the battery and so on. It is not really your peak demand, but your daily comsumption that you have to cover. For that, you need to know your hours of sun

But lots of people have done this already, and there is a program you can link to from my website, from the Canadian government, that has a worldwide database of weather. You input your demands, the panels you are using, etc and it gives you the size required. Now, I am using it for solar water heating, but they have it for electricity as well. It is linked here: (it runs under MS excel)

http://www.freefuelforever.com/index_files/Page701.htm

[Jim Franklin]

Ursula, I would consider a combination of Solar and Wind generation in your situation.

Most (but not all) panels are available in 120W units, but there are some about rated at 220W, and they do not come cheap when added together..

I would suggest that you generate about 2kW from Solar (10 to 20 panels depending on rating), and the rest from either a single or twin turbines. Twin would be best as it would mean generayion could continue whilst maintenance took place or it failed totally.

Further, I would suggest you calculate your total likely daily requirement, and then add 25% to allow for expansion, then I would at another 30% to this total and this is what you should look to generate. So based on your 5.5kWhr estimate above, you should look to have a generation capacity of about 8.9kW and thus storage. The reason being is that your actual usuage will go through peaks and troughs, and the peaks may be higher than 5.5kWhr. It also aloows for failures and maintenance of parts of the system.

Regarding the storage, I would suggest that you allow for the storage of about 24hrs worth of electricity if you want to be totally independant from the grid as this would allow you too absorb periods of high use and low wind..or even high wind when the turbines will not operate.

Then you need to consider the inverter, this should be rated at about 50% higher capacity that you would normally average as it would allow you to absorb the peaks without risking damage to the equipment, and allow some headroom for future increases in consumption.

Hope this helps.