Winter and Solar Panels???

I'm not sure if I'm calculating this right but I'm trying to decide whether solar is really worth it. A 1KW system puts off 1kW per hour right? maybe i have that wrong.

If it's 1kWH for $7,000 and i'm paying my electric coop on average 6.5 cents per kWH then the way I see it I would have to get the full power out of that panel 24 hours a day 7 days a week for 12 years to just break even. That doesn't account for the system breaking down and needing repairs and replacements.

Short of the "going green" reason, I'm hard pressed to find a reason to go with a solar system at this point.

Of course, 90% of the HA stuff I've done in my home doesn't give me any return on my investment at all but I did it anyway. It's just cool! :ph34r:

Its like anything else, it depends on the situation...

I'll confess that I've always thought Solar was "Cool" :ph34r:, I've never really looked at it from a long term financial position (although many do..), I kind of look at it as being "my power" once purchased. My power here (AEP) works out to about $.10 per KWH (1000 watts for 1 hour is 1 KWH, as you said). Since I have both separate systems installed, it offsets what I do use (sometimes only 400 KWHs/month), and I can eventually tie-in the power from the new array to charge my other "back-up" system. To me, being able to stay warm and cozy when the power is knocked out during say an ice storm while the neighbors are sitting cold in the dark, is PRICELESS :o.

A lot of places in the country have alot higher KWH pricing too, which figures in as well in the economics of it, and prices have no where to go but up these days...

One other situation for Solar (a battery/inverter system) is for folks who say build a place not connected to the "grid" even though it may not be very far from a power line. The prices the power companies want per tenth of mile to connect you are astronomical! In these cases its cheaper to put your own solar installation (or other alternative) then to pay the electric companies to connect to their system.

But hey, first experiment with a small panel (10 watts or so) and battery if nothing else, and see what you might want to eventually do with Solar. A good quality panel is warranted for 20-25 years, and you never know when you'll have a use for it to power a light or something at the house or in the yard...
 
I'm not sure if I'm calculating this right but I'm trying to decide whether solar is really worth it. A 1KW system puts off 1kW per hour right? maybe i have that wrong.

If it's 1kWH for $7,000 and i'm paying my electric coop on average 6.5 cents per kWH then the way I see it I would have to get the full power out of that panel 24 hours a day 7 days a week for 12 years to just break even. That doesn't account for the system breaking down and needing repairs and replacements.

Short of the "going green" reason, I'm hard pressed to find a reason to go with a solar system at this point.

Of course, 90% of the HA stuff I've done in my home doesn't give me any return on my investment at all but I did it anyway. It's just cool! :ph34r:


If you go to bpsolar.com they have a savings estimator, and according to the estimator......
If I install a 1KW system the installation will cost me $2,844 after all the rebates and save me $16 a month.
So to break even it would take me 14 years to break even.

If I install a 5KW system the installation will cost me $16,750 and the monthly savings $82 month.
So to break even it would take me 17 years to break even.

I don't think the site has updated to the latest electric price jump, I am up to 22.5 cents a KW.
So, 5KW an hour * 4 ( 4 hours optimal for my area year round )
20KW a day * 23 days for a month ( assuming 7 days of non-optimal power due to weather ).
Thats 460KW a month * .225 is a savings of 103.50 a month.
So to break even it would take me 13.5 years at the current electric rates.

Any of them still seems a very very long time to break even, except prices keep going up. My electric went up 7 cents a KW on my July bill and they just passed another 3 cent increase within a couple of months with an additional 5 to 8 cents in a couple of years for the electric delivery.

This is all assuming I did the math right, I did flunk math in school :ph34r:.

StevenE
 
Yeah it really seems like solar panels are nowhere near ready for primetime. But if we don't have good folks shelling out the cash now for them then the prices won't drop near as fast. So you guys keep buying them up so folks like Steve and I can buy them for half price in 5 years. :ph34r:

I just thought of another aspect to this. Instead of buying a 5kW system for 17,000 you can take that initial investment and put it in some sort of cd or fund that gets a good rate of return and pay for your electric bills that way. :ph34r:

I think I'm missing the point though, the whole reason for this is to "save the planet" and what-not.
 
Yeah it really seems like solar panels are nowhere near ready for primetime. But if we don't have good folks shelling out the cash now for them then the prices won't drop near as fast. So you guys keep buying them up so folks like Steve and I can buy them for half price in 5 years. :ph34r:

I just thought of another aspect to this. Instead of buying a 5kW system for 17,000 you can take that initial investment and put it in some sort of cd or fund that gets a good rate of return and pay for your electric bills that way. :ph34r:

I think I'm missing the point though, the whole reason for this is to "save the planet" and what-not.


Cheaper photovoltaics are just now becomming available, Nanosolar claims that they will be able to sell panels for $1 a watt. I paid over $500 for 80 watt panels I bought around 1995.

Here are some links if you are interested on printed thin film photovoltaics.
http://en.wikipedia.org/wiki/Nanosolar
http://www.nanosolar.com/
http://www.nanosolar.com/blog3/
 
They claim they have a one-year production backlog!

Yes, but it might be a good solution if you can wait. It would be nice if you could really buy 5kw worth of panels for $5000.


I'm curious about what kind of longevity, and long term power falloff the "thin film" cells might have. Most "thin-film/amorphous" panels output drops off fairly significantly when new. Single crystal and Polycrystal Silicon are typically rated to no more than 10% power loss for the first 20 years.
 
They claim they have a one-year production backlog!

Yes, but it might be a good solution if you can wait. It would be nice if you could really buy 5kw worth of panels for $5000.


I'm curious about what kind of longevity, and long term power falloff the "thin film" cells might have. Most "thin-film/amorphous" panels output drops off fairly significantly when new. Single crystal and Polycrystal Silicon are typically rated to no more than 10% power loss for the first 20 years.

I would like to see info on that too, The first PV panels I bought were amorphous silicon, unframed squares I found at a Electronic surplus store, they lost about 20% of their original power in a very short period of time. I have an Arco Solar Monocrystalline panel that was used in a PV power plant here in California, they used mirrors on the sides to concentrate more light on it, it turned brown and is putting out about 30% less power than it used to.
Arco shut down the PV plant because the PV panels were degraded up to 10% per year.

http://ieeexplore.ieee.org/Xplore/login.js...+Schlueter%2C+L.

I bought new polycrystalline 80 watt panels and used them without noticable power drop for years.
 
Loss of output power over time is the main reason I went with THESE Mitsubishi panels (for a work related project).

They warrant the panel for less then 10% power loss over ten years, and 20% over 25 years.

MEUS additionally warrants for the Solar Panels that:

if, within ten (10) years from the date of manufacture printed on the module label, any Photovoltaic Module exhibits a power output less than 90% of the minimum Pmax at Standard Test Conditions as specified on the manufacturer’s Product Information Label affixed to each Photovoltaic Module, provided that such loss in power is determined by MEUS (at its sole and absolute discretion) to be due to defects in material or workmanship, MEUS will, at its sole option, either replace such loss in power by providing to the VAR additional Solar Panels to make up such loss in power; [2] repair or replace the defective Solar Panels; or [3] refund a prorated portion of the Purchase Price at an annual depreciation rate of four percent (4)% of the Purchase Price.

For the Solar Panels, MEUS further warrants that:
if, within a period of twenty-five (25) years from date of manufacture printed on the module label any Photovoltaic Module exhibits a power output less than 80% of the minimum Pmax at Standard Test Conditions, provided that such loss in power is determined by MEUS (at its sole and absolute discretion) to be due to defects in material or workmanship, MEUS will, at its sole option, either [1] replace such loss in power by providing to the VAR additional Solar Panels to make up such loss in power; [2] repair or replace the defective Solar Panels; or [3] refund a prorated portion of the Purchase Price at an annual depreciation rate of four per cent (4%) of the Purchase Price.
 
I sent the Enphase company and e-mail, as well as called. Their units ues communications over the power line to talk to their EMU device.

It's how they report all that's going on with the inverters. I asked to see how compatible this is with UPB switches, as well as if I can monitor the data myself (instead of uploading everything to them...don't really like the idea of someone besides me monitoring ... well .. me

--Dan
 
I sent the Enphase company and e-mail, as well as called. Their units ues communications over the power line to talk to their EMU device.

It's how they report all that's going on with the inverters. I asked to see how compatible this is with UPB switches, as well as if I can monitor the data myself (instead of uploading everything to them...don't really like the idea of someone besides me monitoring ... well .. me

--Dan

Let us know how that pans out with the Enphase Modules, as they do seem promising(at least in concept), if you want to avoid a "centralized" Grid-Tie Inverter. Seems a bit cheaper too, although I'm not sure how much the "monitoring" adds to the cost. I'm not exactly full of enthusiasm for central monitoring by Enphase (facts and figures for marketing?) , that is kind of like the aversion I have to using an "online" site to backup computer files...

The out of production "OK4" modules I have, just used an RS-232 arrangement with a interface device (small hub).

I have an "energy detective" too, but it pretty much screwed up X-10 AND Insteon for me, so I went with Z-Wave instead of Power Line stuff.
 
So far:

"Dan,

According to one of our hardware engineers the communication for our micro-inverters is at a higher frequency than the X10, which as you said is at 120kHz. He does not believe that the X10 will interfere with the communication of our EMU and micro-inverter. However, he is unable to conclude whether or not our products would interfere with the X10 communication because we have not tested them in the presence of such a system, and because that is dependent on the X10 receiver. If you have any more technical details on the X10, I would be happy to provide them to our engineers to see if we can get a more concrete answer.

Regards,
"

So, I sent technical spec. sheets detailing X10 and UPB (to the point to how long between bits, where they should arrive, the tolerances, etc.).

I also requested more information regarding their protocol. I'd like to satisfy myself as well!

Will post more as I get anything from them.

--Dan
 
So far:

"Dan,

According to one of our hardware engineers the communication for our micro-inverters is at a higher frequency than the X10, which as you said is at 120kHz. He does not believe that the X10 will interfere with the communication of our EMU and micro-inverter. However, he is unable to conclude whether or not our products would interfere with the X10 communication because we have not tested them in the presence of such a system, and because that is dependent on the X10 receiver. If you have any more technical details on the X10, I would be happy to provide them to our engineers to see if we can get a more concrete answer.

Regards,
"

So, I sent technical spec. sheets detailing X10 and UPB (to the point to how long between bits, where they should arrive, the tolerances, etc.).

I also requested more information regarding their protocol. I'd like to satisfy myself as well!

Will post more as I get anything from them.

--Dan

Still haven't received my DC Disconnect and take a "completed" pic of the Inverter setup, but after two weeks or so of operation under Ohio skies... I'm seeing a production total of about 76 KWHs at the moment.

Gotta check to see if where that Disconnect is... may be strapped to the back of a "Yak", and is still lost somewhere in the mountains...<_<
 
You have 6 120W panels?

I've been running some numbers to convince the wife, and as we are in NY, I figure your Sunny Ohio is similar (albeit slightly more sunny) then my house...

So, where is the 76KWh coming from? Maybe I threw a wrong number in somewhere...

--Dan
 
You have 6 120W panels?

I've been running some numbers to convince the wife, and as we are in NY, I figure your Sunny Ohio is similar (albeit slightly more sunny) then my house...

So, where is the 76KWh coming from? Maybe I threw a wrong number in somewhere...

--Dan
mdiehl said he had 5 x 200W panels. The 76 KWH would be a cumulative number, he cannot produce 76 KW, that little "h" is sneaky. ;)
 
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