amuck-landowner

Anyone running solar powered stuff at home?

Neo

Member
Nothing, sometimes i use it to charge my Nokia 3410.


Yes, but there are also days which return you less power because its a cloudy day, in the Sommer yes.


So they ended up saying in a Forum 150WP minimum with 80AH Battery, which is enought to power a Raspberry PI B+ 350mA for like 7 Days without any sun and a Raspberry Zero which draws like only 100mA even longer like 21 days. 150WP Because there is also Winter and Cloudy days,


And that brings it to like 400-500EUR of costs, if you run that thing on grid its like 7EUR per Year.
 

drmike

100% Tier-1 Gogent
Solar ROI is still broken / not there usually.  Panels are rated / warrantied at 20 years often and lifespan able to be longer than that.  Problem is batteries are about 5 years on average, meaning factor in 4-5 battery purchases.   Controllers go also.  Low input and draw stuff like this shouldn't be too brutal on controllers so we should factor at least 2 controllers over system life.


Let's breakout some numbers on how solar competes.  We'll go with an ARM device with average draw of 5 watts.  


5 x 720 hours = 3600 watt hours or 3.6KwH a month.


@ 20 cents per KwH = 72 cents per month electric cost  = $8.64/year
@ 15 cents per KwH = 54 cents per month electric cost = $6.48/year
@ 10 cents per KwH = 36 cents per month electric cost = $4.32/year


Even when we extend these out to say 10 years, the ROI isn't there.  Top most costly (and an electric rate unrealized in the US at this point) yields $86.40 for a decade.. Compare that vs. panel + controller + wiring + batteries.


Soooo.... Solar remains good where you are:

  1. off grid or electric service is too expensive to run to your location (i.e. rural)
  2. using solar as backup redundancy in case of grid failure
  3. niche hobby applications with emphasis on smaller wattage panels and use

This is all even worse this year as I see solar panels have again floated up in price on small buys (i.e. one off 200 watt or smaller panels).  With China dumping the per watt price sunk well below $1, now it seems to be quite high comparatively.  $120 panel I bought last year has gone up a good $50.
 

Neo

Member
No price change here, Paying still 57EUR for 50WP with Shipping, 87EUR for 80WP or 100WP for 76EUR.


The Only thing that increased are the battery costs it seems.
 

drmike

100% Tier-1 Gogent
No price change here, Paying still 57EUR for 50WP with Shipping, 87EUR for 80WP or 100WP for 76EUR.


The Only thing that increased are the battery costs it seems.

Those prices are up... at least from this side of the pond.


87EUR for 80W works out to $1.21 USD...  So comparatively, yes an increase.  


Last year I was seeing commonly $1~ shipped per watt.  Sad I didn't pick up more panels for project :(
 

Neo

Member
Never had something different, 100WP is still like under 80EUR the rest was always priced like that.


Since 2 Years.
 

drmike

100% Tier-1 Gogent
Never had something different, 100WP is still like under 80EUR the rest was always priced like that.


Since 2 Years.

Probably good and proper import tariffs working on your side of the pond.   One of the rare times as a consumer the broken system may have had a financial benefit as a buyer here. Usually such is buying inferior goods and questionable workmanship and certainly no customer support.


China was clearly dumping panels and cells here in the States.  Import stuff over here is rather lacking.  One more reason I can support Trump in his presidential run.  Tariffs are vital to protecting domestic industries from sovereign economic warfare funds that demolish companies by dropping prices, taking market share and killing that competitor, then to possess the market for themselves.
 

MannDude

Just a dude
vpsBoard Founder
Moderator
Last year I was seeing commonly $1~ shipped per watt.  Sad I didn't pick up more panels for project :(

Where at? Any particular brands or just... eBay Chinese stuff?


All my 100watt panels are from Renogy, and my future ones will be as well. Can probably get them cheaper, can certainly get them more expensive, but Renogy seems like a good company and I doubt they'll be going belly up anytime soon. Support has been good and the product and reviews have been good as well.
 

drmike

100% Tier-1 Gogent
Where at? Any particular brands or just... eBay Chinese stuff?


All my 100watt panels are from Renogy, and my future ones will be as well. Can probably get them cheaper, can certainly get them more expensive, but Renogy seems like a good company and I doubt they'll be going belly up anytime soon. Support has been good and the product and reviews have been good as well.

Unisolar.   A defunct US manufacturer that has been parted to China I do believe.  They were up in Michigan.


Plenty of 'old stock' of their panels.  Notably flexible panels like these:
http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=unisolar&rh=i%3Aaps%2Ck%3Aunisolar


Single panel right now is a full $100 more than I paid last year for a 130W+ panel.


I like these panels since you can in theory bend them and shape things.  Also mounting is via adhesive backing.  So no crazy mounts (which add up and if you live in some zoning hell hole require all sorts of permits and inspections and massively build up on wind sheering effect on your roof).
 

Neo

Member
Still trying to get a RaspberryPI Zero, as i heard it only needs 65mA when it idles, which is perfect for my Solar setup.


Setup it with a 12v Monitor, neat but its really hard to get one. If you dont't want to spend like 50$.
 

drmike

100% Tier-1 Gogent
Still trying to get a RaspberryPI Zero, as i heard it only needs 65mA when it idles, which is perfect for my Solar setup.


Setup it with a 12v Monitor, neat but its really hard to get one. If you dont't want to spend like 50$.

Just so you know, most electronics internally are purely DC.  Might need to tap in where the wall wart was externally and remove that, might need to pigtail the internal power board and remove it from equation if power is done inside monitor.


Part of why I don't get guys with solar setups running computers and related on AC power - doing the multiple stages of losses.  Simple to pigtail things and BOOM on DC power and more efficient.


How big did you @Neo go on your monitor?  
 

Neo

Member
I am still having everything running on DC, even my Notebook and Netbook.


Well these losses when you running it from DC > AC > DC, to huge.


Just buy a Power Supply which runs on 12v and puts it up to 18-21v, which i am using on my devices.


I got some crappy from EBay, but the resultion is garbage, need to get some premium 7" TFT which runs also on 12v but that costs me another 60$.
 

drmike

100% Tier-1 Gogent
I am still having everything running on DC, even my Notebook and Netbook.


Well these losses when you running it from DC > AC > DC, to huge.


Just buy a Power Supply which runs on 12v and puts it up to 18-21v, which i am using on my devices.


I got some crappy from EBay, but the resultion is garbage, need to get some premium 7" TFT which runs also on 12v but that costs me another 60$.

Keep stuff running DC.  No reason to penalize yourself and draw power down doing unnecessary power conversion losses.


Monitors are hard to find advertised directly as DC.  They treat them like exotic or something.  Never understood the niche on pricing with DC monitors.  Check out the Lapdock Motorola put out.... might be a solution - know people did RPi laptops from those.  Then again, probably up there in cost.
 

MannDude

Just a dude
vpsBoard Founder
Moderator
Tomorrow I plan on switching my solar stuff over to my new battery bank and actually putting the system to some use:


homOyKK.jpg


xp3XK8w.jpg


Just 3X 100Ah 12V batteries right now. If I had a bigger bank I could fit four in there or if I rearranged them differently I could maybe get one more in there without having to buy or build a new cabinet for them.


The second photo is a 12V motion sensor tied to a 12V battery health meter... It works but it'd be more optimal to just wire the meter to a switch. Motion sensor draws power when idle, not a lot, but enough to make it worth just using a switch to power on the LED display. Just using it for shits-n-gigs now.


I'll update tomorrow after I get everything hooked up.
 

drmike

100% Tier-1 Gogent
Just curious, what's the lifetime for the batteries for solar? 6 years?

If even...  Depends on how you utilize your batteries...


If you keep them mostly full on charge (requires regular power in without overcharging them) and don't deep discharge (should discharge like 25% of battery ever or severely reduces life of battery) then with better batteries you can get 5+ years out of them.  Batteries are by far the most horrendous part of solar.  They are expensive, heavy, toxic and dangerous.  For off grid, about all you have as an option.   For grid tied, you can get a grid tie inverter.  That will distribute power to your main line and overflow - if you actually are 'producing' more than consuming - will go past meter (at least traditional ones) back to the grid.  Advantage to this is you get rid of the dreaded batteries and do not to go wiring things with alternative 12VDC plugs.  Disadvantage to utility company is people feeding back to powerlines can be a safety issue for utility workers, but on small systems, meh, overblown BS.


Guys with solar and interested in long haul (i.e. batteries that will last as long as their panels) should look at Edison batteries.
 

raj

Active Member
Disadvantage to utility company is people feeding back to powerlines can be a safety issue for utility workers, but on small systems, meh, overblown BS.

Many utilities require the use of grid tie inverters that feature a safety disconnect switch that will isolate your panels from the grid upon loss of grid power to prevent energizing de-energized portions of the grid from dispersed power generating resources.
 

drmike

100% Tier-1 Gogent
Many utilities require the use of grid tie inverters that feature a safety disconnect switch that will isolate your panels from the grid upon loss of grid power to prevent energizing de-energized portions of the grid from dispersed power generating resources.

Dealing with grid tie officially is nothing short of miserable. Permits, electrician, inspection, etc.


Everything they recommend should be done if you have a generator also....   Usually that's a facility entry main switch to drop the grid feed.  Today surely are automated ones out there that monitor both sides and have logic to auto switch.


I've never viewed grid tie as a good idea.  Lots of people bought into the hype with them as a utility generation plant and income model for what they didn't use.  I tend to size things small to just covering actual use... so amount I'd ever feed to the grid would be zero.  Grid tie here is sheerly for convenience of using 110v plugs anywhere without rewiring.


I realize the topic of grid tie like this is a tad rogue ;)
 
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