Solar power anyone?

[Frunple]

damage, there are no batteries. the power generated is sent to the grid. thats why there are two meters. one is the meter you have now measuring your usage off the grid. the other is connected to the panels measuring their generation. the difference is either paid, if you use more than you generate of owed to you if the other way.
 
keep in mind, the panels do not need to be on your roof if you have land space. most systems here in the northeast are being installed on the ground these days. of course, as said, if you have the land space. could end up an eyesore if not.

 

[bpwwer]

I live in Northern California so sun is not an issue, especially
during the summertime. I also have a large roof facing the right direction to
take advantage of the sun.
For those who have done it: Is this a wise investment? Did
you ever break even and if so how long did it take? Is your electricity bill
$0? Were you able to negate the monthly equipment payments due to the reduction
in your electricity bill, or were you still paying extra?
Thanks for any insight.

We had solar installed about 4 years ago so it has not paid for itself yet. We have ~6kw system on the roof. For the most part we stay on tier 1 with 1 or 2 months where we'll generate more than we use. We expect it to take 9 - 10 years to recover our investment. Our house is all electric so that made the decision a bit easier.

We're in northern CA also. I've been tracking our use and production since the system was installed. PM me if you want to take a look at the charts.

 

[damage]

damage, there are no batteries. the power generated is sent to the grid. thats why there are two meters. one is the meter you have now measuring your usage off the grid. the other is connected to the panels measuring their generation. the difference is either paid, if you use more than you generate of owed to you if the other way.
 
keep in mind, the panels do not need to be on your roof if you have land space. most systems here in the northeast are being installed on the ground these days. of course, as said, if you have the land space. could end up an eyesore if not.

 
we have what's called net metering where only 1 meter is needed. when we generate more than we use, the meter spins backwards.

 

[tmbrown97]

You probably won't get direct power of the house via solar without batteries or something to balance the load.
 
RichardU - I'm adding Atlanta into the list of places I'd like to move when I leave CA  ^_^  Power here is stupidly expensive - I use about 2,200kwh/month peak in the summer... you?  (I'm sure your answer will make me sick).

 

[RichardU]

RichardU - I'm adding Atlanta into the list of places I'd like to move when I leave CA  ^_^  Power here is stupidly expensive - I use about 2,200kwh/month peak in the summer... you?  (I'm sure your answer will make me sick).

So you can make an accurate comparison, here are my rates this year.
 
WINTER – NOVEMBER 1 - APRIL 30 BILLING
 
Service Charge   @ $ 20.00   per mo.
First 900 kWh    @    8.891¢ per kWh
Over 900 kWh    @     9.165¢ per kWh

 SUMMER - MAY 1 - OCTOBER 31 BILLING
 
Service Charge   @ $ 20.00   per mo.
First 900 kWh    @    8.891¢ per kWh
Over 900 kWh    @   13.185¢ per kWh

 

[damage]

this is a good tool for estimating how much production per month you can achieve based on your location, array size, orientation, angle, conversion efficiency, etc http://goo.gl/w5nXi
 
Richard, those are super cheap rates.  our lowest tier is more costly than your highest rate.  somewhere over 900 kwh, we'd be paying 34 cents/kwh.

 

[dgage]

I was reading an article in the Feb 13 edition of Popular Science and it mentioned the issue of having a solar system pushing juice to the grid while employees are working on it.  They also mentioned that such a device to disconnect from the grid during a power outage were too expensive for residential use but that one of the people in the article had developed a device that they hoped to sell in the local hardware stores for around $500.  I guess I am out of the solar party until that device is made available for residential systems.  I can't wait...open savings account now for solar panels.
 
David

 

[RichardU]

They also mentioned that such a device to disconnect from the grid during a power outage were too expensive for residential use 
David

 
Why you couldn't you use a transfer switch which is used commonly for generators? They are not cheap, but they are readily available.

 

[gatchel]

RichardU - That is what I want the ability to do.  If there is a humongous storm where the power out for a week plus (Sandy recently), it would be pretty bad to have $10K+ in solar panels on the roof but still be without power.  I don't necessarily want a battery system but I would want the ability to disconnect/reroute so I can at least use solar if the power is out.  If I could figure that out, then it would be a no brainer (although when I get to it is another story).
 
David

 
Simulate a sine wave on the power lines and your solar inverters will begin to operate.
If you really want to know how things work search out MPPT or read this:
 
http://en.wikipedia.org/wiki/Maximum_power_point_tracking
 
A grid tied system provides a somewhat constant power production with the incoming grid power being a "capacitor" of sorts.
 
Your solar array may be able to provide X amount of watts of power with out the grid connected but what happens when the refrigerator starts up and pulls double or triple the wattage you are capable of producing?  That's where the batteries com in.
 
If you want power in  an outage you need an Islanding Inverter and storage batteries.
 
http://www.sma-america.com/en_US/products/off-grid-inverters.html

 

[dgage]

Part of this discussion focused on the DIY packages such as the Westinghouse system that Lowe's has available for order. The surprise was that the system would be out of commission if the power went out.  I'm sure if we rolled our own system that we could get an islanding inverter (didn't know what it was called before so thanks) but hopefully future packages will have it built in.  Then again, I'm the type of DIYer (as are many on Cocoontech) that would learn everything about the subject and be able to roll their own package from best of breed parts.  So thanks for sharing the links.
 
David

 

[RichardU]

Your solar array may be able to provide X amount of watts of power with out the grid connected but what happens when the refrigerator starts up and pulls double or triple the wattage you are capable of producing?  That's where the batteries com in.

 
The same problem exists for generators. But generators don't need batteries because they can run at night.

 

[tmbrown97]

When I looked at the westinghouse solution it looked like you could also get it without the microinverters - probably a better way to go if you're looking to introduce the battery backup as well.
 
Very educational thread for sure.

 

[dgage]

I read somewhere that microinverters were not as efficient as a single inverter when compared directly but as a system the microinverters were overall a better (opinion?) design due to individual panels working at their peak efficiency.  Having a single inverter puts the efficiency equal to the least efficient panel.  Also, more chance of a system being taken out if the inverter fails while only one panel will be affected by a microinverter  failure.  I'm sure I'm simplifying but it gets the point across although I'm sure there are other arguments that say a single inverter is a good solution too.
 
David

 

[wkearney99]

we put in a 3.7kw array almost 3 years ago.  net cost after rebates & tax credits was a little over 12k paid in full.  we use 600-750 kwh per month and the first 2 years, the panels generated 75% and 67% 

 
What was your initial out of pocket cost and how long until the rebates were paid?  Tax credits are great but carrying the expense until tax time is certainly an issue.  We're completing the build of a new house and I've space on the roof for PV panels.  But whether I'll have cash to spend on the panels has yet to be determined.  So I might actually postpone the installation of them until Fall of '13 when there's end of year cash available and I'm closer to being able to file the taxes for it.

 

[Westcojack]

We live in Los Angeles and had solar panels installed November 2012.
We researched for around 3 months and spoke to 3 larger local companies.
We settled on one company as they provided the following system:
9KW in panels, 1 inverter, 2 meters (a utility company requirerment), upgraded the existing panel to 200 amps (we have a 4000 sf home, no a/c and no electric cooking/heating or hot water)
We leased the system, paid no $ down. We are paying $.20 per kwh for the produced kwh's for the next 20 years (the rate goes up 3% per year.)
The solar company expects to provide 80% of our needs on a yearly basis.
So far some months we over produced (most summer months), and some around 40%-50% of what we use.
In total before solar we were spending $ 360/mo-$410 /mo to SCE (our utility company), now it averages $220/mo for solar and $70/mo to SCE. We are saving around $ 100 per month.
The over production turns our SCE meter backwards. 100% of the maintenance and repairs for the 20 years are included in our payments.
So far the upside is that we are saving $ 100/mo now, and expect that with the skyrocketing increases in the utility company bills we ill save more as the years go by. The downside are ugly solar panels on the front roof of our home.