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$100 Amazon Credit, can start solar from scratch?  RSS feed

 
Morgan Louis
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Location: USDA zone 8b
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I have $100 in gift cards on amazon, I was wondering if I can build a small solar package with that amount.

Can you all help me build a little system? I haven't ever done or before so I need to get everything. Just enough to charge a cell phone or an led light bulb.

Thanks in advance!
 
Tobias Ber
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Location: Northern Germany (Zone 8a)
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hey... if you want to build it yourself, you could go for a 30-50 watt solar panel and a cheap (10-20$) charge controller.

battery would be far more expensive, but yout could try to find a used 12V car battery.

12V LED lamps (spots work well) should be around 5$.

like these: http://www.amazon.com/12x5730SMD-550-570LM-6000-6500K-LED-Bulb/dp/B00FAI40S0/ref=sr_1_8?ie=UTF8&qid=1447579762&sr=8-8&keywords=12v+LED+spot

or these: http://www.amazon.com/cutequeen-Holagen-Replacemnt-Camper-Trailer/dp/B00BLYCZA2/ref=sr_1_50?ie=UTF8&qid=1447579926&sr=8-50&keywords=12v+LED+g4


There are converters from 12V to USB-power which are designed to be plugged in the car-jack where the thing goes to light cigarettes. these can be found cheap, i got one in a 1€ store.
like these: http://www.amazon.com/Vafru-2P-3-1A-Certified-Charger-Technology/dp/B010KA3ZMY/ref=sr_1_14?ie=UTF8&qid=1447580007&sr=8-14&keywords=car+jack+usb

i started to learn things with this video

 
Troy Rhodes
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It is an education in itself to do an ebay search for "40 watt solar panel"

http://www.ebay.com/itm/HQRP-KIT-40-Watt-20-20-Monocrystalline-12V-Solar-Panels-10A-Charge-Controller-/151371011433?hash=item233e6a5569:g:M0QAAOSwnDZT2383

A hundred bucks will get you a panel, a charge controller and possibly some connectors.


The chinese have figured out how to make quite inexpensive solar panels. This is available through ebay, but hasn't quite trickled down into amazon. I find the amazon prices about double what the ebay prices are for equivalent panels in this size.

So, maybe buy 100 bucks worth of stuff that you need on amazon, and use the saved money to buy a kit on ebay.

The battery will run you another hundred bucks or so.

Automotive starter batteries are terrible, they hate deep discharge and it kills them rapidly.

Deep cycle batteries for trolling motors (sometimes referred to as marine batteries) are better.

golf cart batteries are much better yet.


If you manage the battery well, you can now almost make electricity for the same price as the utility will sell it to you.

So I would not view this as a money saving operation. But you do get some independence and learn some excellent skills. It's almost certainly better for the environment.

The utility electricity enjoys considerable subsidies, so the true cost is probably quite a bit better from the solar electricity.


 
Morgan Louis
Posts: 33
Location: USDA zone 8b
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Thank you both Tobias and Troy. I watched the videos by lds self reliance and found them to be exactly what I needed. And that deal on eBay for the two panels and charge controller is pretty nice. A few years ago I was looking on a site called alibaba or something and they had pretty cheap solar equipment.

Troy, when you said that this would not be a money saving operation, it confused me. Will I not eventually produce enough energy to pay for the equipment?
 
Troy Rhodes
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How much does your current provider charge for a kilowatt-hour?

Then we'll do a little two minute math problem and find out how long your payback would be.
 
Morgan Louis
Posts: 33
Location: USDA zone 8b
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My dome-yurt is off grid right now. I just charge my phone/laptop at work, But I looked up the rates in my area and the baseline is $0.77 per kilowatt-hour, but the total is like $1.19 after transportation and procurement costs.

 
Tobias Ber
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Location: Northern Germany (Zone 8a)
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morgan,
ok, then you would most likely save money with solar.

for your laptop there might be a 12V mains adapter. this would help to save on watts of panels and batteries for your solar system.

do you plan to build a bigger scale system? if yes, this might help you: [youtube]https://www.youtube.com/playlist?list=PLoHd6hGDqS06g0umrn4XO0Wk9JyZcTfMa[/youtube]

i ve learnt a lot through this series.

the big question is: how much electricity do you need and how much can you pay?
 
Troy Rhodes
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My what expensive electricity you have...

That's ten times what I pay.

Back of the napkin calculations...

40 watt panels only produce 40 watts under perfect conditions, and conditions are generally less than perfect. Let's say you can mount them at a good angle and in real life, you can collect 34 watts for an average of 4 hours per day.

34 watts x 4 hours = 136 watt-hours per day

but we need KILOwatt-hours, so

136 watt-hours/1000 = 0.136 kilowatt-hours per day

Again, round figures, let's multiply that times your rate of a buck a kilowatt-hour (holy crap, where to you live)

0.136 kilowatt-hours x $1.00 = $0.136, or let's call it 13 cents a day.

That's 13 cents x 30 days = $3.90 a month you'd save.

Let's say a hundred bucks for the panels and 70 dollars for a battery like this:

http://www.amazon.com/dp/B00K8E0WAG?psc=1

a thirty dollar, 400 watt inverter that you use sparingly. It's more efficient to use the 12 V directly than it is to convert it up to 120V:

http://www.amazon.com/Cobra-400-Watt-12-Volt-120-Volt-Inverter/dp/B001RNOHBC

Twenty bucks for other bits and pieces like wire, a fuse, some sockets,


100 + 70 + 30 + 20 = $220


$220 / $3.90 per month = 56 month payback period. Just a touch under 5 years, at which point the battery will be pretty much worn out, and possibly the cheap chinese inverter as well.

But you gain considerable independence and self reliance, and a whole new skill set, and a tiny bit of saving the planet, so there's that.


Bigger systems get quite a bit cheaper per kilowatt hour, but cost more up front.
 
Tobias Ber
Posts: 495
Location: Northern Germany (Zone 8a)
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troy, yay ... good calculations. i was on the same line of thinking there. and wondering how that can be so expensive. maybe he s in a remote location.

morgan, is there electricity already in your yurt? or would you have to pay to get it installed? i mean, is there a power supply or would the power company charge you to get it on your land?

would you have to pay a monthly fee with your electricity? like 30$ per month + cost per kWh

 
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