How do I go about powering appliances from solar energy

Question

I would like to learn how to power some house hold appliances from solar energy.

I haven't had any experience with electronics but am eager to spent time reading and experimenting.

I've done a little Googling which has been interesting for a start but has also raised some more questions.

I've seen a wide range of specifications for small solar systems, batteries, converters and inverters but haven't been able to work out the best combination to use to power say, a TV, a caravan fridge, a laptop and a microwave.

Is there a formula that I can use to calculate the specs required for the solar panel/inverter/batteries and inverter?

A description of a working system with examples of what the system is powering and the sunlight hours required to keep it alive would be very helpful.

Answer 1

Take for example this solar cell. It has a maximum peak power output of 1W, and you can fit about 130 of them in on square meter. This would be 130W peak output. "Peak output" would be at the equator at midday on a clear day. You can adjust for latitude and time-of-day using simple trigonometry and add a factor for cloud cover. My feeling is that, depending on your geography and climate, you'd be lucky to get a tenth of that as a peak on any given day under regular circumstances.

All this conspires to require very large surfaces if you need to produce enough power to power appliances.

Answer 2

Solar cells can't generally be used to power appliances continuously (unless you have very big ones or expensive ones).

However, what you can do is use them to charge a battery. You can then use this battery to power your appliances directly if they are 12v (such as a caravan appliance) or via an AC inverter.

Depending on the amount of energy hitting the solar cell, the battery will charge very slowly. So after a full day of charging, you might only be able to power your appliances for around 5 to 30 mins at a time, also depending on the power consumed by the appliance.

If you had datasheets for the solar cells and batteries, and power ratings for the appliances, then it might be possible to more accurately predict how long you can power stuff for.