Off-Grid Volt Charger

Fatawan

This is a brainstorming question. What would it take to make an off-grid charging station for a Chevrolet Volt? I ask because my utility limits backyarders to 10kW systems(which I have) before they bump you into a "generator" class where your costs skyrocket. So if I am maxed out on my grid tie, what could I do to provide the 8.8kWh/day it takes to charge up the Volt? Would panels + inverter + batteries do the trick?

Thanks

BB.

Re: Off-Grid Volt Charger

Probably not worth the cost of batteries+inverter+maintenance.

Any way I have cut it, a "off grid" battery based system will cost you around $1-$2+ per kWH (in the US--assuming 20 year life, replacement of inverter/charger/battery bank around year 10)... Or about 10x what most people pay for grid power.

Your better bet is usually conservation... A 10 kW system should be able to generate quite a bit of power in a day (40-60+ kWH per day 9 months of the year?).

If you can figure out how to reduce your grid power load (A/C, heating, lighting, electronics, well pumping, etc.)--Then look at alternatives.

There are several good options that you can put your money into that may save you quite a bit of power (again, depends on where you live, your existing utility connections like natural gas, weather heating/cooling loads, etc.).

• Lots of ceiling insulation, wall insulation, double pane windows
• Heat pump A/C and Heating systems (air source, ground sourced)
• solar panel powered well pump (pump to cistern, use small AC or DC pump for local pressurization)
• Solar Thermal systems (domestic hot water, space heating)
• Look at entertainment systems (many consume lots of power--frequently left on by kids, sometimes lots of "standby" power for DVRs and Sat Receivers)
• Look at computer usage (turn off when not needed, use laptops for day to day web surfing, turn off printers when not in use, etc.).

Anyway, this thread has lots of various projects and information sources that may give you some good ideas.

Working Thread for Solar Beginner Post/FAQ

-Bill

Fatawan

Re: Off-Grid Volt Charger

Thanks for the fast response Bill. We live efficiently now, but there is always room for improvement! I will keep digging.

My main system has been up for 2 months, and I have banged out a bunch of mid 60's kWH days(best of 68.6). I am way ahead on the utility meter for now.

BB.

Re: Off-Grid Volt Charger

Much of the equation regarding costs will be based on your local utility's net metering plan (1 month, 1 year, tiered rates, etc.).

1/2 the "engineering" of Grid Tied solar systems is playing MBA with the utility rate plan(s).

We have 1 year net metering (yea), tiered power (5x cost differences between cheap night and peak/heavy user summer peak--boo; except I would get paid 5x for GT generation; yea).

-Bill

solar_dave

Re: Off-Grid Volt Charger

I own a Chevy Volt and my 12.5 kW system is more than enough to charge it, run up to three 3 ton AC units, run a VFD swimming pool pump and only have to buy just about $200 annually from the utility off peak for night time AC usage during the worst of the summer months (read that as real cheap electric). Here in AZ the AC is a huge item but conservation is your friend. We still cook with electric (some induction, some standalone appliance like crock pot, griddle, lots of outside grilling, ...) but have converted to solar hot water. So far since May we have used 0.6 gallons of gas in about 2800 miles of driving the Volt. Hell my barbecue grill has used way more fuel.

We had all of this in mind when we scaled the system 2.5 years ago. It has worked out great. The guys on this site have been the best when coming up with ways to conserve, the off gridders still amaze me. Not knowing your location I suspect if your net metering is setup correctly, you have a TOU plan and load shift to give you the kWh, and do the max conservation routines you will be way OK charging your Volt.

Last month I still had 1300+ kWh of on peak excess on my utility TOU plan and we moved the Volt charging to anytime we want (immediate charge at plug in). That being said we should also be able to charge a second Volt with no issues.

My second Volt (red tint coat, neutral leather interior, polished wheels, fully loaded) is now on order:
10/03/2011 (2000) Order accepted by GM. Dealer used allocation to place order into production.
10/04/2011 (2500) Order preferenced. Order pulled to the production system.

Nothing like Driving for FREE with no OPEC FEE!

rollandelliott

Re: Off-Grid Volt Charger

"my utility limits backyarders to 10kW systems(which I have) before they bump you into a "generator" class "

just curious how would your electricty company know if you added to your pv system and made it bigger? It's not like they can just drive by and say, that looks like a 12kw system and not a 10kw system. Of course if you make it a 20kw system it would be obvious due to it being very very big.

icarus

Re: Off-Grid Volt Charger

rollandelliott wrote: »

"my utility limits backyarders to 10kW systems(which I have) before they bump you into a "generator" class "

just curious how would your electricty company know if you added to your pv system and made it bigger? It's not like they can just drive by and say, that looks like a 12kw system and not a 10kw system. Of course if you make it a 20kw system it would be obvious due to it being very very big.

My guess is that pulling an electrical permit would trigger the utility knowing that your system is changing. Not pulling a permit would likely jeopardize your insurance.


Tony