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Has anyone tried using a solar array to charge their Volt? I'm thinking if 4 panels or so can charge my Volt a coupla times a week I might try it.
I'm figuring on using an inverter to provide 120 volt ac.
But I suspect, that since the amps would vary (0 at night for example) that it may trigger some internal Volt monitor that would automatically shut down charging and would require a manual re-set to start charging again. Is that true?
Is it possible to contact GM for questions like this?
Has anyone built a solar Volt charger? Any advice?
Thanks!
 

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Most of us use grid tied solar and a wall outlet to charge, thus achieving solar powered Volts without the complexity/effort. We did have a member building a fancy direct solar charging off grid setup in the early days, and I think he got it working, but he hasn't been around here recently.
 

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Here is a satisfied Volt owner using solar...
https://www.revisionenergy.com/solar-power-for-your-home/electric-vehicle-charging/

Some amazing facts:

Just 9 solar panels provide roughly enough electricity to power 12,000 miles of electric driving each year
Level II charging station delivers full vehicle battery charge in 4 to 8 hours depending on vehicle range
If you would otherwise drive a 20mpg vehicle, your solar electric panels charging your electric car will pay for themselves in around 2 years. Over 20 years, this will be like paying $0.32/gal for gasoline!*
One of our customers, who has a Volt, tells his story:

The Chevy Volt of Evan Sohm, owner of a solarized home in Londonderry, NH.

I drive from Londonderry, NH to Methuen, MA for work, Monday through Friday. It’s approximately a 37 mile round trip; the Volt will go approximately 40 miles on 10 kWh of charge. As a result, I’ve been driving the Volt to and from work without using any gas.

The PV solar panels on my roof produce 4 kW of power in full sun. So if the sun shines on my roof for 2.5 hours, that produces 10 kWh of energy which is enough to drive the car for 40 miles! On average our PV system produces 18.9 kWh/day. If you use all that energy to charge the Volt you could drive 75 miles per day with zero fuel expenses.

If we drove a regular car that gets 25 mpg for 75 miles, that would require 3 gallons of gas. So for us, it’s like our solar panels produce 3 gallons of gas per day, every day.

I couldn’t be happier, because in all honesty, I hate giving my money to the oil companies. Not only do I get to save money and help the environment, but I get to drive a really cool car! Everybody who takes a ride in it says it’s like a spaceship. But the Chevy Volt is not rocket science. It’s like any other regular car, only more efficient. So far, I’ve driven 7,000 miles and the lifetime fuel economy is 107 mpg. – Evan Sohm, Londonderry, NH
 

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Most of us use grid tied solar and a wall outlet to charge, thus achieving solar powered Volts without the complexity/effort. We did have a member building a fancy direct solar charging off grid setup in the early days, and I think he got it working, but he hasn't been around here recently.
I agree, a grid tied system is the way to go versus trying to solar charge directly. I've had a grid tied system for seven years. We now charge our Volt and a LEAF. We settle up with the utility once a year and I normally owe them $80 to $120.
 

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Has anyone tried using a solar array to charge their Volt? I'm thinking if 4 panels or so
What sized panels?

Almost every solar newbie woefully overestimates the generation capability of solar.

I'm not pooh-poohing the idea, I'm just saying that in order to provide the minimum of [email protected] to provide even a low speed level 1 charge on a Volt...you need a significant amount of square footage in solar panels.
 

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Has anyone tried using a solar array to charge their Volt? I'm thinking if 4 panels or so can charge my Volt a coupla times a week I might try it.
Thanks!
A single full charge on a GEN1 needs about 14kwh, about 18kwh for a Gen2

4 100 watt solar panels might make 2kwh a day, not account for how your convert to a method to charge the car

This doesn't even begin to get into how 400 watt peak solar can power a 1kw minimum EVSE at 8 amps 120VAC.
 

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A single full charge on a GEN1 needs about 14kwh, about 18kwh for a Gen2

4 100 watt solar panels might make 2kwh a day, not account for how your convert to a method to charge the car

This doesn't even begin to get into how 400 watt peak solar can power a 1kw minimum EVSE at 8 amps 120VAC.
Hundred watt 12V panels are expensive per watt anyway. Since he didn't specify, I was assuming he meant 4 standard big panels - 260-290W rated per panel, which means in ideal conditions he'd have enough power for 120V @ 8A charging. Of course, that's ideal conditions, and wouldn't be all day...
 

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Volt will attempt to draw a minimum of 8A @120V with the supplied EVSE. Or about 1000W. Even with 4x 300W panels, the chances that the inverter will be able to supply 1000W are slim to none. Five panels might do it for a few hours around local noon, if the panels are aligned properly.

I've been able to build a pulse charger, where even a single panel can charge a buffer battery (or even the Volt 12V battery), then the battery powers an inverter for a brief period to power the EVSE and charge the car from the J1772 input. A micro-controller (or some process) must monitor power in from solar, power out to the car, and cycle the inverter on and off, to make sure the buffer battery is not discharged. Not very efficient, not really worthwhile. Better to just put the same panels on your home roof.
 

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We are using solar grid tied and it works seamlessly. We of course charge our Volts religiously and get a bit of our home heating from from mini split heat pump. This in addition to all normal electric usuage results in a near zero dollar annual cost after covering the monthly $17 connection fee. I could not be happier.
 

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Discussion Starter #10
Solar Volt Charger

It looks like grid tie is the way to go. If I self created a 1500 watt system I would have excess power at times and would want to use it. That would open a can-o-worms for me and would greatly enlarge the $1200 or so budget target (don't laugh!). My impression is that turn-key grid tie systems are $20,000+ but I'll check on that. If I snagged an old Leaf battery, the pulse charge system would work great!
I love this forum! Hope you all would never think I would feel smug when a fancy ICE Mercedes passes me! Way too shallow.
Thanks.
 

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I have a solar array on my home, which generates on average ~30kWh per day. It generates enough energy to fully charge my Volt & power all the needs of the house (including HVAC). I'm very happy with the setup.
 

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I have a solar array on my home, which generates on average ~30kWh per day. It generates enough energy to fully charge my Volt & power all the needs of the house (including HVAC). I'm very happy with the setup.
Awesome, but what did it cost...and how much does it generate on a rainy/cloudy day?
 

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I still don't see roof solar as an option for me.

- I already get 100% wind power from my provider, so, no ecology help there.
- The cost of roof solar is more than buying grid power.
- I buy wind-generated power at 6.9c/kWh plus delivery and taxes.
- We get lots of hail.
 

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It looks like grid tie is the way to go. If I self created a 1500 watt system I would have excess power at times and would want to use it. That would open a can-o-worms for me and would greatly enlarge the $1200 or so budget target (don't laugh!). My impression is that turn-key grid tie systems are $20,000+ but I'll check on that. If I snagged an old Leaf battery, the pulse charge system would work great!
I love this forum! Hope you all would never think I would feel smug when a fancy ICE Mercedes passes me! Way too shallow.
Thanks.
In December 2015, the Consolidated Appropriations Act extended the 30% credit for residential solar to the end of 2019. It then steps down over two years and expires completely at the end of 2021.

30% for systems placed in service by 12/31/2019
26% for systems placed in service after 12/31/2019 and before 01/01/2021
22% for systems placed in service after 12/31/2020 and before 01/01/2022
There is no maximum credit for systems placed in service after 2008.
Systems must be placed in service on or after January 1, 2006, and on or before December 31, 2021.
The home served by the system does not have to be the taxpayer’s principal residence.
 

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You would need 14-16 panels to be able to provide 3700 watts to charge at the full level 2 capability of the car's on board charging system... and then only at times around solar noon. you need to be grid-tied, or running a battery bank which could capture energy over a longer period of time which can also deliver the power.
 

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Awesome, but what did it cost...and how much does it generate on a rainy/cloudy day?
It cost me $10k out of pocket (after figuring in all the rebates, incentives, etc). I figured my ROI was going to be ~7 years based on my electrical bills alone. Now that I've purchased the Volt and almost all mileage is exclusively electric from that move, my ROI should be considerably shorter since I'm no longer spending that gas money for the prior ICE commuter car. Doing a quick recalc based on prior average yearly cost of gas of ~$1500....mathmathmathguessworkmath...

...oh, looks like I've already passed the the ROI point and all that money I was spending towards electrical bills and gas is already going into my pocket.

As for the rainy/cloudy day question, I'm sure that could put a damper on things, but I live in southern California where that's not much of an issue. My calcs are all based on average annual figures...I suppose for a more cloudy/northern climate, the solution would be to increase the number of panels (which would introduce a higher initial cost), but it's still doable. After all, Germany has already done it, and they're climate isn't always sunny.
 

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I would really like to see more research into improving solar efficiency. Perhaps someday we will reach the point a solar panel covering the Volts roof, trunk and hood will be enough to top off during the day sitting outside.

Alternative means such as wind might be possible for some.
The local power company claims to use Solar and Wind to offset your cars charging. I'm not sure how much they generate via solar as the two local "farms" are rather small.
 

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I, too, have a grid-tied solar system. September marked the two year anniversary of it going live. When we were planning the array I had it sized for 110% of our useage from the three previous years, hoping to use it for an EV in the future.

Numbers:
System size: 5.6kW, producing 32kWh per day averaged across a year
Comprised of 16 360W Sunpower panels + 1 6kW inverter
Cost: $30,000 full cost
-$9,000 (federal renewable energy rebate)
-$3,000 (state renewable energy rebate)
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$18,000 - our final cost

Aside from not having an electric bill, we were receiving a check for ~$25 every month for the excess power purchased by the local utility company. The system would have paid for itself after 9 years.

I purchased the 2017 Volt mid-January 2017. In the 10 months that we have had it, it has cut into our excess production somewhat. Instead of a check every month from the utility company, it is just about every other month (any time the balance goes over $20 in credit). Looking at the latest 10 month data, I have figured out that our system will pay for itself after 10 years. The panels have a 25 year warranty, so hopefully we'll have a number of years beyond 10 where the system will really pay off. The inverter is guaranteed for 10 years and that will be an expensive unit to replace. Hopefully future costs will be lower. Already within the last two years, a system such as ours can be purchased for around $26K now.

Lastly, my daily commute is 53 miles each way. I am charging every weekday at home on an L2 (4 - 4.5hrs). I can just about make it to my office; the last 5-6 miles uses the ICE. I charge at the office (sometimes using the 1 available L2, sometimes with the 110V outlet) and I can make it all the way home with 15% charge remaining. I have been getting 2,000 to 2,700 miles per tank of gas. :)
 
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