paul wheaton wrote:I think you can follow me on kickstarter. I've never used that feature, so I don't know how that works. Here is my last kickstarter.
Marcos Buenijo wrote:Listen to podcasts available at www.battery1234.com. Also note that Steven Harris has done about 15 such podcasts on The Survival Podcast hosted by Jack Spirco. These are packed with practical alternative energy information.
Steven Harris considers the hydrogen production from batteries to be neglible, but you'll have to listen to the podcasts to get his full discussion (starts at 65:45 of part 1).
Marcos Buenijo wrote:
Hi David. Where can you buy the computer you mention here, and what kind of pricing are we looking at?
Cj Verde wrote:Well, we run our whole house. We do have a sun frost fridge/freezer which we've had for like 20 years but the fridge part hasn't really worked work well for a few years & even new I wasn't totally thrilled for the price.
The point is reduce your energy consumption - big time! We do run our generator quite a bit during the winter especially to run our pump. A great thing we did last winter was to put the pump on a timer switch because we used to turn it on and if we forgot to turn it off it would really run down the battery if the pump kicked on.
There are things you should just do without like a frost free freezer or a toaster oven or AC or electric dryer or electric water heater....
We do have a DSL modem on all the time (sometimes I'll put a timer on it so its off for 6 hours while everyone should be sleeping - I've got 2 teenagers). I do have a small aquaponics setup and the pump runs 15 minutes / hour (15 minutes / 3 hours at night). My husband isn't thrill about that though. He thinks its a drag on the batteries.
Cj Verde wrote:No, that's not what I meant.
100 watts dc 12v is like 10 watts ac 120v!
I'm used to thinking in amps though. So my when my charge controller says we're getting in 40 amps on a sunny day that's great but the well pump uses 11 amps AC which is 110 amps DC! See?
Cj Verde wrote:Here's an important formula:
watts/volts = amps
Cj Verde wrote:One more thing for reference.
I have 17 panels of various wattage and the smallest chest freezer I can find. I only run it late spring/summer early fall so I'll be turning off soon. Of course, my whole house is off-grid, and I live in Vermont which I think gets an average of 4 hours over the year!
Cj Verde wrote:
David Taylor wrote:
One 100 Watt solar panel producing 80 Watts per hour (after system loss) for 6 hours a day is 480 Watts or .48 kWh per day. Right?
So (2) 100 Watt panels would be .96 and (3) would be 1.44; enough for the freezer and then some.
Not quite. I think you've forgot about converting 12v to 120v.
Marcos Buenijo wrote:
David Taylor wrote:Thanks Tom, I had forgotten about the loss in the charge controller and inverter. And did not know about only getting 6 hours due to the angle of the sun at morning and night. Looks like Ill be getting another panel. Had planned on it anyway, just need to do it sooner now =)
Hi David. A 200 watt off grid system is not nearly enough for 1.4 KWh per day. Also, the battery may have to be larger than you think as well. Also, please note that the battery losses can be substantial. Figure battery losses on the order fo 20-30%, inverter losses at about 15%, and controller losses at least 5%. Add other losses like transmission losses and dust/debris on the panels and you're looking at overall losses of nearly 50% for an off grid solar PV system. A conservative estimate of actual production can be found by taking the product (solar insolation)(PV array wattage)(0.5).
Marcos Buenijo wrote:Hi David. A 200 watt off grid system is not nearly enough for 1.4 kWh per day. Also, the battery is going to be larger than you think as well.