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What would need to happen so that one could set up a car-port with solar panels and charge the Volt JUST from them? Meaning, no other system/inverter/transformer... meaning, when clouds go over, the car just takes in less power. Is this possible?
 

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There are two kinds of solar installs:

a) On Grid - This has to "see" utility power. It will only work with utility power present.

b) Off Grid - This is what you would be looking at.
 

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Be kind of tough to buffer the solar with a car alone. EVSEs are pretty picky about their voltage and grounding. Also, your car would need to be parked during the day. Otherwise electricity is generated but not used.

There are probably full kits out there by now.
 

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Not possible as designed.

The only way the Volt has to put power into the car is through the J1772 plug. That is connected to the charger module, and it expects to receive 100-250V 50-60Hz AC power.

Photovoltaic panels by their nature are DC devices, outputting 60V DC each in the typical consumer panel.

So clearly some sort of electronics will be necessary to marry the two. The output of the solar panels is variable depending on the conditions - a system large enough to charge the car in the early morning our late afternoon will be producing more power than the car can take at noon, and the car isn't designed to handle the disruption when a cloud floats overhead.

Is it possible to build a stand alone system just to charge a car? Yes. But it is far more practical to build a solar system that's tired to the grid and connect the car to that. (Unless you're in a place where the grid isn't available or reliable.)
 

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What would need to happen so that one could set up a car-port with solar panels and charge the Volt JUST from them? Meaning, no other system/inverter/transformer... meaning, when clouds go over, the car just takes in less power. Is this possible?
At the very least you'll need panels, an inverter, and an EVSE. In theory it should be possible to adjust the charge rate on the fly by adjusting the pilot signal sent by the EVSE (probably a custom unit based on OpenEVSE)

Assuming you had 4000 watts available you could have a 16 amp pilot signal and the Volt would charge at full speed. If cloud cover reduced the available power to 2000 watts the pilot signal could change to 8 amps. I'm not sure of the actual granularity of the Volt's onboard charger, but I believe you can adjust the charge current in steps of 2 amps or less.
 

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What would need to happen so that one could set up a car-port with solar panels and charge the Volt JUST from them? Meaning, no other system/inverter/transformer... meaning, when clouds go over, the car just takes in less power. Is this possible?
Here you go: I think they cost $30 - $40k ____ Self-Contained Solar EV Charging Station

 

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What would need to happen so that one could set up a car-port with solar panels and charge the Volt JUST from them? Meaning, no other system/inverter/transformer... meaning, when clouds go over, the car just takes in less power. Is this possible?
It would cost a lot because you'd need a battery bank to even out the power when a cloud passes by etc....

MrEnergyCzar
 

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Discussion Starter #8
clarify

I guess I should clarify. I live off grid on solar power, bought one of the first Volts and have gone 20,000 miles on 11 gallons of gas - the rest is all from the sun!

But I already had a solar power system on my house.

What about for people that don't have or want (the extra expense) of all that seemingly unnecessary equipment?

What would need to be added or modified so that someone could simply throw 9 solar panels on the roof of their garage and whatever power comes in, goes in the car. If it's super cloudy, it just doesn't get much power that day. Super-simple.

Because I can tell you as an early adaptor, even with my fairly large PV system on my house (5kw) (and I charge at 240v - fast charger) you really don't want to charge the cars battery from your houses batteries too much (such as early morning or cloudy times) - it's too hard on the batteries and will harm them, costing more than you saved on the gas you didn't have to buy.
 

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I guess I should clarify. I live off grid on solar power, bought one of the first Volts and have gone 20,000 miles on 11 gallons of gas - the rest is all from the sun!

But I already had a solar power system on my house.

What about for people that don't have or want (the extra expense) of all that seemingly unnecessary equipment?

What would need to be added or modified so that someone could simply throw 9 solar panels on the roof of their garage and whatever power comes in, goes in the car. If it's super cloudy, it just doesn't get much power that day. Super-simple.

Because I can tell you as an early adaptor, even with my fairly large PV system on my house (5kw) (and I charge at 240v - fast charger) you really don't want to charge the cars battery from your houses batteries too much (such as early morning or cloudy times) - it's too hard on the batteries and will harm them, costing more than you saved on the gas you didn't have to buy.
You might want to search for DCFusor's posts about the "bang bang" controller he built for his off grid solar system. It basically only runs the car charger once the house batteries are full.

I still say if you are on the grid, a grid tie system with net metering is the most effective way to offset you Volt's consumption. No batteries required and you get the full benefit of the watts even if the car is fully charged. It also allows you to use those watts at a time different than when they are generated.
 

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Isn't there a huge need for this? There should be! If someone wants to charge their car with solar power, why should they have to buy a whole separate bank of batteries when the car already has a huge battery?

Someone clearly needs to sell a device (GM?) that can go between solar panels and a EV simplifying the system and sending the power directly to the cars.
 

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Isn't there a huge need for this? There should be! If someone wants to charge their car with solar power, why should they have to buy a whole separate bank of batteries when the car already has a huge battery?

Someone clearly needs to sell a device (GM?) that can go between solar panels and a EV simplifying the system and sending the power directly to the cars.
The down side to that is the car has to be there when the power is generated. Otherwise there is no place for it to go and the photons give you nothing for your expense. This is where grid tie solar comes into play, you get to run your meter "backwards" and then consume the power when you want, not necessarily when the sun is at its peak output. In effect the grid becomes your 100% efficient storage.
 

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Yeah but where many people, myself included, live there is no grid-tie option available.

Solar Dave - how big is the system on your house? Do you charge your car at night? Level 1 or 2?
 

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Yeah but where many people, myself included, live there is no grid-tie option available.

Solar Dave - how big is the system on your house? Do you charge your car at night? Level 1 or 2?
Well my system is 12.5 Kw and I pretty much charge the cars in the daytime, but I am retired now finally (I hope it sticks). We have a pair of L2 chargers. One of the reasons we try to use daytime is that the TOU/net metering plan here doesn't allow moving generated watts between day and night hours. Both cars are set to charge immediate but they tend to get used in the daytime hours.

Where do you live?
 

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Voltsoundz, The biggest challenge are the requirements of the Volt for its input. First, the Volt expects to do a negotiation with its input device. So you would need a device which does the the same negotiation as the EVSE. Next you need an inverter which outputs the appropriate voltage since the Volt expects AC input. Finally, and perhaps the most challenging, you would need a method to start up charging when sufficient current is available, stop it and when current drops below necessary level, and start charging back up when current levels return. Each time the charging is to resume the system would need to renegotiate with the Volt. If you wanted to get really fancy the system could start charging at 120 8 amp, then as the panels increase output, shut down charging, then renengotiate at 120 12 amp, and of course you could have another level going to 240 volt.

Although such a system could be developed, I doubt there is much demand. For those on grid, which is the large majority of Volt owners, a grid tie system is more practical. So this solution would be for those off grid, whose cars are usually at home during the day (a minority), want a system separate from their home system and own a Volt.
 

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12-8-6 amps
 

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New SMA Grid Tie inverter with 1.5KW backup outlet could be a standalone option

I guess I should clarify. I live off grid on solar power, bought one of the first Volts and have gone 20,000 miles on 11 gallons of gas - the rest is all from the sun!

But I already had a solar power system on my house.

What about for people that don't have or want (the extra expense) of all that seemingly unnecessary equipment?

What would need to be added or modified so that someone could simply throw 9 solar panels on the roof of their garage and whatever power comes in, goes in the car. If it's super cloudy, it just doesn't get much power that day. Super-simple.

Because I can tell you as an early adaptor, even with my fairly large PV system on my house (5kw) (and I charge at 240v - fast charger) you really don't want to charge the cars battery from your houses batteries too much (such as early morning or cloudy times) - it's too hard on the batteries and will harm them, costing more than you saved on the gas you didn't have to buy.
Hello,
have you heard about the new SUNNY BOY 3000TL-US inverter with backup outlet?

Here are two links:
http://www.youtube.com/watch?v=fF461YYNbtw&list=PL840A5336CAC32332&index=30
http://www.sma-america.com/en_US/products/grid-tied-inverters/sunny-boy/sunny-boy-3000tl-us-4000tl-us-5000tl-us.html

It is a new Grid tied inverter with a 120V backup outlet that provides up to 1500W when the grid is down.
If I understand that concept correctly, it will provide AC power without any AC voltage being detected on the grid side. In case of a power outage it manually needs to be switched to the SPS mode (secure power supply). I guess, you could install it stand alone with PV panels connected and it will provide 120AC as long as the sun shines.
It should work safely with the LVL 1 VOLTEK charger at 8 AMPS, which draws about 900W continous.

Minimum number of panels I guess would be 6x250W to get close to the 1500W at peak time. The smallest inverter model can handle 3000W when it is grid tied, which means you can go probably up to 14x250W panels, depending on where you live. This would sustain the 1500W SPS outlet for many hours during the day, I would think.

If my math is right, under ideal conditions you could get one full charge per day for a VOLT on the SPS outlet.

Also it might be an option to use your 5KW Off Grid system as "the Grid". So, if you don´t charge the VOLT, you could feed additional 240V AC power into your existing system during the day. I have never tried this, but technically I can´t think of any reasons, why this should not be possible. The grid tied inverter should sync to the AC sine wave of your existing inverter, and provide more AC wattage, which would free up some DC load for battery charging right?

I haven´t checked any prices. SMA ist the first company that just came out with this option. I bet that others will follow.

Best
Roland
 
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