I want...

[BrookValley]

...a solar system to power/charge my laptop. That's it. The battery on my laptop doesn't last very long (an hour or two) and so I pretty much leave the machine plugged in all the time. It's the one piece of electronic equipment (aside from our fridge/freezer) that stays "plugged in" all the time. And I'm sure it's a big drain--nevermind the fact that I'd like to be able to use it even if the power is out.

The problem is, the thing (according to the battery pack) requires 65 Watts (240 Volts) of power. That's not insignificant. The cheap little solar chargers made for laptops (those little backpack things) aren't going to cut it. And neither is any other small solar charging or generator system that I can afford. If my research is correct, I'd need a system that's going to put me out at least $300--probably more--to run this computer.

Any ideas? I don't want to spend more than, say, $100. I don't see why this thing would need such a complicated or expensive set-up...

 

[Urban Farms]

I have seen cheap solar generators at home depot

 

[big brown horse]

Same at Costco!

 

[PamsPride]

In order for me to use a solar generator I would need SUN!!! It is raining here AGAIN today! I think we have had 5 days of sunshine all summer!

 

[Urban Farms]

how about a wind mill?

 

[TanksHill]

Modern Pioneer was just talking on his journal about building something similar. He is using it for his cash register and stuff at trade shows. I asked him to post some pics when he has time. You might want to drop in and ask him some questions.

 

[xpc]

Your laptop charger probably says 65 watt 240 volt but that is the max it is capable of handling, you more than likely plug it into a 120 volt outlet and probably draws around 25 watts depending on the application running and when in sleep or power saver mode only a few watts.

Before I get into what you need let me first tell you that if you continuously ran the laptop for 12 hour a day for a full month it would cost about $1.50 in electricity at 15 cent a kilowatt and assuming a 30 watt hour draw. My Mac costs about a dollar a month to run for 8 hours a day.

Even with a $200, 45 watt solar pv cell you would still need a deep cycle battery for the dark and cloudy days. A 10 amp @ 20 hour battery will cost about $100, charge controller about $25, and a small inverter about $30, a smaller 15 watt solar cell at about $75 - Total parts about $230 for the 15 watt or $355 for the 45 watter..

If starting with a fully charged battery you could run the laptop for about 40 hours of continuous use, this is based on 30 watts usage with a Depth of Discharge of only 50% so the battery will last 5 years, a deeper DoD will shorten its life.

On a five hour sunny day the 15 watt pv cell will recharge approximately 75 watts or about 2.5 hours of usage, the 45 watt one will be about 225 watts or 7.5 hours of usage. The 12vdc to 120vac inverter will more than likely have a 15% efficiency hit so you have to de-rate by that amount, pure sine wave inverters are much more efficient but cost about $600.

At 50% usage the battery will need 1200 watts to fully recharge and will take 80 hours of sunlight at 15 watts and 27 hours at 45 watts. Even a big $1000 - 200 watt pv cell will take 6 hours to fully recharge it, without the laptop running.

I hope this makes up your mind.