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You will need, A battery to store the electricity from the solar panel. The amount of electricity from the panel varies up and down as things such as clouds, position of the sun, etc. reduce the amount of solar rays hitting the panel. The battery stores it all, the ups and downs, and sends it back out at a steady voltage so you can operate your p.c. / appliance.

A minimum of 45 watts solar panel. 60 watts would be preferable. 45 watts will charge a battery in one day under ideal conditions. You turn the panel as the sun moves across the sky, no clouds. 60 watts will charge a battery in one day with out moving and regardless of clouds.

A controler to prevent the electricity from flowing backwards from the battery to the solar panel when the sun goes behind a cloud or sets at night and the charge drops below the voltage of the battery. A good controller will tell you the charge condition of your battery so you know when it is too low to operate your p.c. safely.

And finally an inverter with “True Sine Wave” capability to change the electricity from the battery into usuable power for your PC and other electronics.

Not all inverters produce true sine wave electricity. The electricity has static in it and will make your pc screen jump around and not function as it should. New digital T.V.’s also require true sine wave electricity to operate. Go the extra cost and get the inverter with true sine wave and be happy with the way your p.c. functions.

Figure out how many Watts your p.c. or appliance will draw. and match the Inverter to the need. Do not go too big, as they cost more and consume more of your stored electricity to operate. Save as much electricity as you can. You will be able to operate your p.c. appliance longer.

When not using your p.c., you can operate your T.V. or other low watt appliance.

Make Residential Solar Panels

I mostly agree with Ranger_co, except for the inverter.

Most laptops have an AC adapter which converts to low voltage DC. The nearest one at hand right now is a Lenovo which outputs at 20 volts by 3.25 amps. If the solar system has least 20 volts (24 most likely), then an extremely efficient system use a custom regulator which outputs at the needed voltage directly to the laptop. It might take some carousing in seedy electronic shops to find the right connector and regulator, but it would more than be worth the effort for the greatly improved efficiency and inherent high reliability.

Perhaps that laptop is atypical. This website says they have DC to DC solutions from 12 V for most laptops.

Make Home Solar Power

First off, you need to know how much power your laptop draws… they vary quite a bit.
After that, you have to figure on gathering near full power about 5-6 hours per day. Sure, you get some power for a lot longer than that but better safe than sorry.
Just for simplicities sake, let’s say your laptop draws 100W. That might be high, I can’t remember for sure.
Now, figure on your inverter being about 80% efficient. Again, they are probably a little better than that but you don’t want to get caught short.
Based on that, you now need 125W for your laptop.
You want to run it for 10 hours… if you only gather power for 5 hours a day (again, being conservative) you have to gather twice what you need to run the laptop so you are up to 250W from the panels.
Now, next to last but not least, how efficient is the charging process.
To be honest, this part I really don’t know much about…
I did find some information on the website listed below that suggests that charging efficiency is about 70%. That gives us 250W divided by .7 or 357W.
My existing solar panel array is rated at 9690W (57 panels at 170W each) and typically delivers about 8000W on a good bright summer day. I get nearly that in the winter too because while the angle of the sun isn’t as optimal, the temperature is lower so the panels are more efficient. 8000W/9690W is about 82% of rated output. I just realized that I already gave an efficiency of 80% for inverter efficiency. Based on this, that’s a good number but actually already includes panel loss so we are still at the 357W number.

We just added 7000W of PV power to our existing grid and the panels we added are 175W each. Two of those would give you 350W… pretty darn close to what we just calculated.

I’ve been fairly pessimistic in some of my numbers here so you might get what you need from smaller panels. You may do quite a bit better if you live in an area with good sunshine that isn’t as hot as where I am (Yuma, AZ). Either way, these are all things that you have to consider, you can certainly adjust those percentages up or down depending on the equipment you have access to.

Also, in my case I’m grid tied so I don’t have the battery concerns that someone off-grid does, we were fortunate in that we got a rebate back from the power company and there are pretty nice tax credits out there when you are grid tied, I don’t know how much of that works if you are off grid.

Good luck to you and kudos to you for being interested in green energy.!!!