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Cost of going solar?

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Racerx22b

@unplggdd on Instagram
Nov 17, 2014
922
1,031
West Palm Beach, FL
I was toying with the idea of going solar at my home. 3200sq ft with 200amp service. Our panel is about maxed out. House built about 5yrs ago. Several 220v breakers for 14/50 outlet, Pool equip (pump and heater), electric stove, electric oven, dryer, 2 AC units... Not sure if that is pertinent info. We have clear souther exposure in south Florida. 30% Federal rebates don't really help me (according to the contractors I spoke with) as I normally get a return when filing taxes.

Called a couple places and was provided a "ball park" quote of $55-$60k for a 12-15kw system. We were speaking in generalities. That would provide me with some minimal power in the event of a power outage. To get a full inverter system I was told to tack on another 30-40%.

Just wondering if this is in the ball park? I was thinking closer to half that based on my gut feeling. Obviously my gut needs to be recalibrated.

Jason
 
Whether you get a tax refund or not is irrelevant for the tax credit. The credit is subtracted from the tax due on your income for the year, regardless of what's already been paid in withholding and estimated taxes. If the contractors selling this stuff doesnt know that, I would be careful trustimg them with anything else.

Anyway the price seems too high compared to Texas, but it can vary by location. Our 7.5kW system was $25,000 last year but that's grid tied, no battery backup.
 
Called a couple places and was provided a "ball park" quote of $55-$60k for a 12-15kw system. We were speaking in generalities. That would provide me with some minimal power in the event of a power outage. To get a full inverter system I was told to tack on another 30-40%.

Just wondering if this is in the ball park? I was thinking closer to half that based on my gut feeling. Obviously my gut needs to be recalibrated.

Jason

DIY isn't too hard; I'm helping a friend with a 15kW DC project that's going to run ~$18k upfront.
 
The federal tax money you get is a tax credit. The money you currently get as a refund from the IRS is excess money that you had withheld from your income that they are returning to you. You probably still paid quite a lot in taxes that they did NOT return to you, and the tax credit would come out of those taxes paid. This means your amount refunded to you would include your normal refund PLUS the all or part of the amount of the tax credit. You will likely receive this tax credit even if you don't pay the amount of the credit in taxes in the year you have the system installed, as it can be carried over to future tax years.

I was able to install my own solar generating system, so my costs were considerably lower than those you list. I can't really help with deciding if the contractor you are working with is worth the amount being charged. The materials for a system that size are very roughly in the $25-30,000 range -- maybe that is what your "gut" is feeling.

I will say that the first step to putting in a solar PV system is to spend the money to decrease your consumption -- it is MUCH more cost effective than installing a system big enough to cover your wasteful ways. Insulate more than the minimum required for your area, install an ultra-efficient air conditioning system, install a solar hot water heater, insulated windows. etc.
 
I got a 10.26kw system for $37,500, installed, before and rebates/credits. Its 3 arrays, Enphase micro inverters, 38 Suniva panels, in Minnesota. My system seems to me that it should be on the expensive side per watt because of three arrays and microinverters. I THINK with a clear southern view you could potentially skip the more costly microinverters because no panels will be getting different levels of sun (shade, orientation, etc.) and have a central inverter.

Bottom line to me is that your price seems pretty high.

I changed to all LED lighting when my Tesla was on order. Seems to have helped a lot. My system makes about 1,000kwh/month and since February my bill has been between -20$ and 9$. I also get a once yearly check for 8 cents per kwh, regardless of use/generation.

It seems like somebody with a south facing roof in FL should be able to make the economics work quite easily. Remember too that the solar will help shade your house and reduce AC use.

As a side note, once you get solar and you realize that money is falling from the sky and you are smart enough to catch it....it just feels so sensible and cool. So don't forget the fun factor and also don't forget to add whatever costs you associate with fossil fuel in your calculations.
 
I have a 15.25Kw system in Central Florida, all electric 3500 sq ft home with a 1400 sq ft air conditioned garage. I run all the equipment you mention plus some. I am producing enough power to have a near 0 Net power bill even with driving the Tesla about 14k miles a year and charging exclusively at home except for long trips.
A lot of Florida homes like mine have tile roofs that hikes the cost of a solar install a bit,extra brackets,labor etc. so I think your ball park estimate is not far off if this is the case.
From what you describe and from my experience you will probably need to upgrade your service entrance from the utility to at least 300amps. I would suggest raising it to 400amps for just slightly more money than the 300amp service. None the less I expect that your ball park estimate doesn't consider the service upgrade costs. It's near impossible to estimate sight unseen the service upgrade cost because there are so many variables specific to each case but plan on at least $5K and as much as $15K of extra cost to do so.
I'm talking above about a grid tied net metered system with SMA inverters that allow for power outage supply to one duplex outlet located at each inverter for power when the sun is shining. A full battery backup system is another $20K or so but bulky with a large bank of batteries that require replacement.
 
In December of 2014 I had a 11.55 kW Solar System installed for $32,000 before the 30% tax credit. It consists of 42 panels SolarWorld 275 W each, 1 SolarEdge 12.4 kW inverter and 42 SolarEdge Power Optimizers with ZigBee wireless monitoring of the system. I chose 11.55 kWatt because our utility multiplies the raw DC output of the system by 85% for the inverter inefficiency which brings the "accountable" system down to just under 10kW (which is their lowest tier).

Last month (May 2015) I produced 1.9 MWh. I expect to produce about 20 MWh over the year.

My contractor is Harvester Solar, Wolfgang Beaugrand, 941-312-1221, or email: [email protected].

You might need to install a sub panel if your breaker box is already full. But because the inverter feeds its energy back to the grid, you won't need to upgrade your service from 200A to anything higher. I have a 200 A service and get along great with 1 Tesla, 1 BMW i3, 3 A/Cs and the other usual appliances.

By the way, I'm in Cape Coral, Florida. If you like to come over and visit my installation, please write me an email to [email protected].

Good luck!

Mike
 
Wow... Some great info on here. Thanks everyone. I took a look at my energy consumption over the past year and have inserted a screen shot below. The red line is the avg temperature and the green bars are energy consumption. I'm sure there is someone smarter than me on here that could give me a rough estimate on the size of the solar system I should look at given my monthly energy use. My peak usage appears to be in June. Somewhere around 2800kwh. Keep in mind I took delivery of my Tesla mid Feb 2015. Drive about 800 miles a month.

Screen Shot 2015-06-14 at 4.37.13 PM.png
 
You are very close to my usage pre solar and pre Tesla. You will need a 15 to 17Kw system if you want to be near or at Net 0. In my case this yields me a $9.06 FPL bill most months which are mandated taxes and fees for being grid connected. After 4 years I have yet to get an end of year reconciliation check from FPL but I have also not payed more than $200 a year for electric usage net taxes and fees. We are adding a Model X to the stable at the end of the year or early next so I'm now considering adding more panels to the existing system to cover it's power requirements. I designed/specified my system with oversized inverters from the get go (15Kw system sizable to 21Kw) so that adding more panels will be simple and less costly. Over specifing the inverters to add future capacity is a no brainer since the incremental cost of the inverters is minimal compared to later replacing undersized ones to add additional capacity I'm talking to my solar contractor next week about adding another 3Kw to 5Kw of capacity to cover the Model X.
By the way, if you do need to upgrade your service entrance, if you contract it through your solar installer the costs become part of allowable costs of the solar install and are eligible for the 30% Fed Tax Credit.
 
That would provide me with some minimal power in the event of a power outage. To get a full inverter system I was told to tack on another 30-40%.

I missed this statement (as did several others who responded, probably) in my first reading of your post.

This statement changes things entirely. A grid-tie system like what most, if not all, of the people who have responded have had installed, does NOT provide any backup power at all. If the grid goes down, so does your solar generating capability (and your electricity to the house).

If this capability was not included in your quote, then the quote is, as others who have more experience dealing with solar contractors have stated, perhaps high. However, if they DID provide some means of backup power, then perhaps the price you were quoted was reasonable, depending on what form of backup is included.

I suspect what you heard as a "full inverter system" would be an off-grid system, although the pricing seems a bit low for that type of system.
 
I would be interested in more information on the do it yourself version where did you order and any certain website you can recommend?

Best deals on solar modules

I've also had positive experiences with;

http://www.civicsolar.com

http://ressupply.com

Some lessons I've learned...
- Pay more for High Efficiency modules; Less work + More Power...
- Use grounding clamps;
- Shoot for the higher end of the MPPT curve when designing a system if 90F+ weather is common in your area.

Useful tool for system design