jamius.com

Very soon I am planning to be living off the grid. Trouble is I am a computer programmer (I make video games) and I am going to need run a laptop (or two) most of the day.

I have two laptops, both are fairly low power, no cd\dvd drives, lots of low power options... the gaming laptop even has the ability to turn off the Nvidia graphics and switch to the low power Intel card.
A) 19V 3.42A output from the adapter (Asus gaming laptop, where I will write most of my code)
B) 12V 3A output from the adapter (901a EeePC, doesn't need to run all day, but my wife will probably use it from time to time, and it will act as a test server sometimes.)

It appears we can get 550watts out of pre-tabbed b-grade solar cells, bought off ebay for about $200. And I'm sure I could put together the casing for them (which we are still looking into), and a charge controller of some sort.
For a battery I am looking at this: http://www.mrsupply.com/mk-battery-gel-type-solar-batteries-8g34.html

I was thinking we could get more juice out of this by skipping an inverter and just making something like this Variable DC power supply: http://www.instructables.com/id/Variabl ... ly-for-15/

At this point I have looked at so many solar calculators and what not that my head is swimming with numbers and possibilities. How far do you think this would get me? I would love to here your opinions and ideas, especially from those of you who work off solar power already.

I like the idea of not converting DC to AC only to have it converted back to DC. Very good idea.

sjvsworldtour wrote:I like the idea of not converting DC to AC only to have it converted back to DC. Very good idea.

I like it too, but I'd be VERY weary of feeding unregulated DC into a computer. The bricks for laptops are part of their power regulation I think. So you'd have to build a nice stable power circuit with capacitors to even out the power and take away the ripples. I'm not very experienced in the area, but I'm sure someone on here is. It COULD be done, but I'd make sure you have EVERYTHING perfect before you go plugging it in. I'd consult an electronics forum first if I were you.

Also, why do you need a SOLAR battery? Wouldn't any deep cell battery work just fine?

Also, it seems like if you used all of your solar cells you'd have a lot of extra power. Even if they aren't operating at optimal efficiency, you only need @100 watts to power your computers.

corrado33 wrote:The bricks for laptops are part of their power regulation I think ... I'd consult an electronics forum first if I were you.

Definitely needs to take care of stabilization as well. Good idea, I'll ask around elsewhere before I burn the thing out

corrado33 wrote:Also, why do you need a SOLAR battery? Wouldn't any deep cell battery work just fine?

Yeah... it just happens to be labled SOLAR, but I picked it because it was the cheapest gel battery with that much power that came up in my searches so far. There was an AGM battery for a similar price... for some reason I thought those vented some kind of gas? I will double check.

corrado33 wrote:Also, it seems like if you used all of your solar cells you'd have a lot of extra power.

Excellent. I'd like to add more batteries as I go, the two laptops are just minimal power usage, lights, fans, a sewing machine, etc would be nice too. Although I expect they would need more batteries?

After further research, I definitely will be using AGM's instead of Gel batteries.

You are moving off grid as in you are moving to a remote rural area off grid? Or just disconnecting from the grid?

As I mentioned in another topic it is my opinion that "going off grid" by choice instead of necessity is usually not as environmentally friendly as reducing power usage and choosing net metered, grid tied renewable power. No batteries and if you need the grid it's there...

greenspree wrote:You are moving off grid as in you are moving to a remote rural area off grid? Or just disconnecting from the grid?
No batteries and if you need the grid it's there...

I always wanted to have my home connected to the grid, but only used when my own personal power (solar/batteries/whatever else) is unavailable. It's safer and you don't have to stress about your power usage all of the time.

And calvin, I was just looking at the power at what I'm guessing is maximum efficiency for the solar panels. In cloudy weather who knows what kind of power you'd get from them. So take my "you'll have extra power" statement with a grain of salt.

It's not about needing more batteries, it's about how your solar panels can keep up with the power usage.

More batteries = more energy stored = you can use more stuff for longer in dark/cloudy weather.

However, if you kept your power usage under the amount of power produced by the panels, you could get by with one battery. You'll want more though. I didn't actually look at the battery, so I don't know how long things would last say... at night. And what if you have a string of three or four cloudy stormy days in a row? That's where extra batteries comes in handy.

Think about it like a glass of water. If you're in the desert and you have a normal drinking glass that holds let's say a cup of water. This is your battery. Let's say there is a water source that drips water out slowly. This is your solar panels. So obviously you'd place the glass under the dripping water to collect water. (Hooking battery to solar panel). So as long as you don't drink more than that dripping water produces you'll always have water right? And eventually your glass will overflow since it can only hold so much. Well what happens if the water source dries up for a few days? If you had had a bigger glass you would have been able to collect more water and you'd be able to span those three days just fine. Right? It's the same way with batteries.

I'm sure you got the idea before my lovely metaphor, but I like to make things into unusual situations haha

greenspree wrote:You are moving off grid as in you are moving to a remote rural area off grid?

I am moving to a similar situation as Jaimie. In fact, in Vermont... and on his property. >_>

corrado33 wrote: In cloudy weather who knows what kind of power you'd get from them. So take my "you'll have extra power" statement with a grain of salt.

Right-o.

These batteries seem great for the price: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=360370158248&ssPageName=STRK:MEWAX:IT#ht_1615wt_1002

I can see Jaimie Cult forming right before my eyes.

I do think you should consider more forms of power than just solar. Wind might be a good choice since Jaimie is already getting into the water power business.