Charging with Solar.

[VickirScott]

I would like to charge my batteries with solar.  Does anyone know what amps and volts to purchase for the inverter?

 

[Fat Fusion]

I think it depends on when you drive your car.  If you drive during the day then you'd want to "bank" the solar power in the grid and draw it at night to charge.  If you drive at night I suppose you could go direct to the car.  You have plenty of light there in Gilroy that's for sure.  My friend recently put a home system on his roof in San Martin and is power neutral, so I plug in when I go there.  :woot:

[Kybuck]

Are you trying to install a home solar power system, or a small system just for the car?

 

The voltage depends on your charging setup - either 120 VAC for Level 1, or 240 VAC for Level 2.

 

Most people have a professional install a system for their house, which is a good idea unless you're a qualified electrician - but if you were, I don't think you'd be asking these questions.  So, I suspect you're trying to install a small system just for your car, which I'd honestly have to recommend against.  A small system isn't going to be anywhere near capable of supplying the power necessary to charge the batteries.  The lowest instantaneous power needed is the slowest (Level 1) charging option - 120 VAC @ ~12 A = 1.44 kW.  For solar power density, 14 W/ft2 is pretty good. which means a minimum of 100 sq ft of solar panels, assuming peak sunshine, ideal location, etc.  This isn't a system you should try to cobble together yourself with random parts.  Call a professional and get a quote for a full home system.

[JATR4]

My buddy has a TESLA and had roof panels installed for $8,000 with rebates.  He is in southern California.  The roof panels don't charge the car.  The panels turn his meter backwards.  He charges with a TESLA 240 charger station.

 

He actually is able to charge his car and pay for a portion of his AC bill with the electricity generated.

 

That would be the way to go but you would have to find a reputable charger

Edited July 13, 2014 at 11:09 PM by JATR4

[murphy]

I have a 10kW PV system (40 panels) on my roof.  It is grid tied which means when I am generating more power than I need it feeds back to the power company.  When it is dark outside the power comes back to me for free.  Once a year in May they pay me for whatever is in my banked power account at their regular price to compare.  Since the system was installed at the end of last September it has generated 8.9  mWh (mega watt hours) of power.  The Federal government paid for 30% of the system as a Federal tax credit.  The state of PA paid $7500.00 directly to the installer which reduced my cost by that amount.  My electric bill is $7.12 per month (the fixed charge for having an account).

 

In addition the state of PA gave me $1000.00 ( not tax free) for purchasing my Energi.  The power company gave me $50.00 (not tax free) for telling them that I purchased a plug-in car.

 

A comment:  No where in the USA is the voltage 220.  The voltage is 240 and is split in half for the 120 volt circuits.  The transformer on the pole has a center tapped 240 volt secondary winding with the center tap being the neutral.  The three wires feeding your house have 240 volts between the two hot wires and 120 volts from each hot wire to the neutral.  The neutral is connected to ground at the first panel, and only the first panel, in your house if you have more than one panel.

[123man]

Murphy, what was your out of pocket cost to you?

I've been looking into solar but don't expect the rebates from IRS or TN that you got.

Maybe no money left for us?

[murphy]

Murphy, what was your out of pocket cost to you?

I've been looking into solar but don't expect the rebates from IRS or TN that you got.

Maybe no money left for us?

Unlike the tax credit for the car, which has to be used all at once, it is my understanding that the Federal solar tax credit carries forward to future years if it can't all be used the first year.

My final cost was about $19,000.00.  The question I always get is what is the break even point.  They usually say it is about 8 years but since I can't predict future electric rates it's impossible to calculate.  They only thing I know for sure is that they aren't going down. 

 

There is also the carbon credit (SREC).  A credit certificate is issued for each megawatt of generation.  Those can be sold to entitys that need to offset their own carbon emissions.  I haven't sold any yet so don't know what they are worth.  There does appear to be an oversupply in PA at this time.

 

 

Break even was not a consideration.  It's an improvement to the house.  It would cost about the same to install an in ground swimming pool which not only doesn't have a break even point but continues to require more money forever.

[Sandroad]

Here are a couple of photos of my solar charging station for my ’17 FFE. One photo shows a ground mounted solar panel array. There are two arrays with six panels each, for a total of 12 panels. At 250 watts for each panel, I have 3000 watts of production capacity. The other photo is of the charging station showing the charge controller, inverter, master switch panel, and 120VAC outlets. Directly below the charging station (but not pictured) are eight deep cycle batteries with a total usable capacity of approximately 7.6Kwh, so the car can be charged completely using the storage batteries going through the inverter. This is an off-the grid system not connected to the utility. It has both level 1 and level 2 charging capabilities, but using the level 2 capability requires full sun on both panel arrays, as well as some additional stored power from the deep cycle batteries. 240VAC charging uses a LOT of power! The charging station was $3800. The batteries and wiring were $1800, and the two solar arrays were $1300 each. So the total investment was $6900. When I ran some numbers on the first year FFE usage for us, it looks like the system will pay for itself in about 7 years. That will be about the time I’ll need to replace the deep cycle storage batteries for another $1800, so total payback time will end up being a bit of a moving target, but likely less than 9 years. All that being said, I didn’t do this for the financial side, I did it for fun, educating myself about solar, and reducing my carbon footprint for transportation. We use the FFE for all local driving, occasional longer trips, and used a total about 25 gallons of gas in our first year of ownership. The rest of the miles were courtesy of the sun! I’ve had a couple folks ask about sourcing the equipment. I get all my solar equipment from Northern Arizona Wind and Sun. They offer both individual items as well as complete pre-built systems like mine.

 

 

Edited April 24, 2018 at 12:55 PM by Sandroad