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Is anyone using a residential level 2 charging station powered by a PV system? If so, what has been your experience? I like the idea of generating enough solar power to at least charge the car. I realize everyone's break-even for the PV system will be a little different, but with the federal and state incentives and for other reasons, it seems like a good way to go. Thoughts?
 

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California PV PG&E systems take about 8-11 years to break even - you'll most likely get a grid tied system - which means extra power you generate during the day is pushed back into the grid - and the grid becomes your battery - you then pull kWh's out of the grid at night at a lower cost - you are credited power at day time rates and use power at night time rates - it normally works out pretty well. Look at your monthly bill and get a local solar installer to provide you with an estimate. With out details as to your location, which way your house/roof face and how many panels you can afford to install (afford in this case means both $$$ and space on your roof) you really can not get any answers from the forums…

basically it comes down to installing a solar system means you write a check up front for some amount of power you're going to produce over the next 25 years (the life of the system) - for myself and my neighbors and friends it basically pencils out to $0.25/kwh over the 25 life of the system - if you're paying more than $0.25 kwh for your power Solar is a win, if you're playing less than $0.25 kWh for solar then it's cheaper to get your power from the power company.
 

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I've had solar since about 2004 - and it's worked out well for me - in CA with PG&E I was breaking into different tier's of power - which meant power I was using over the course of the month was getting more and more expensive - Tier 1 and Tier 2 power was pretty cheap but Tier 3 & 4 were down right expensive ($0.65 kWh anyone) - installing the solar system did _NOT_ wipe out my electric bills but I stopped breaking into Tier 3 & 4 on a monthly basis which dramatically lowered my PG&E bills (at the cost of installing a solar system) - turns out Tier 3 & 4 were all more than $0.25 kWh and Tier 1 & 2 are less - so I stopped chasing "zero" because given the cost of the system to install PG&E is delivering Tier 1 & 2 power cheaper than I can produce it myself with my own system. However I am now a 3 eV family - and my power usage is once again creeping up - so I'm upgrading my system so I can once again get cheap Tier 1 & 2 power from PG&E and offset my usage by over producing during the day and avoiding monthly bills that use Tier 3 & 4… I've also recently moved to a EV-A plan from PG&E - where off peak power is 0.12/kwh between 11 pm & 7 am and most of the day on weekends - run the house 24 hours a day and only charge the cars during off peak - add in a little solar production and my bills should be quite manageable for the next several years regardless of what happens to actual retail power rates.

basically it all comes down to: how much are you paying now, most residential power providers these days will NOT pay you for over production - so the best you can do is "zero" out your bill. If you're bill is $120/month, the most a solar system can save you is $120/month - which is $1440/year - if you install a $20,000 solar system then it will take 13.8 years to break even at a savings of $1440/year- if you're paying $6000 year then the payback is quicker - but it depends on the size of your system and how much power it can offset. Summer produces more power than winter (longer vs. shorter days and different angle of the sun) so the power production is not constant through out the year. Modest systems that offset some of your power are quite affordable, systems that overproduce and take care of _ALL_ of your power usage are normally quite expensive as chasing those last few kWh's on the monthly bill require more panels.

I have 48 panels on two separate roof's on my home and the system produces approximately 9 mega-watt hours a year - and I use about 12 mega-watt hours a year - so I end up paying for 3-4 mega watts on my annual PG&E bill. Sunny winter days my system produces 18 kWh's/day - and sunny summer day it produces 45 kWh/days - and anywhere in between on a sine-wave curve as the earth transitions around the sun - cloudy days or rainy days I'm lucky to produce 8 kWh's - and some days I produce next to no power - using the grid to make up for the loss.

my panels are sharp panels that were 180 watt panels (best case 180 watts) each, but they produce less in morning/afternoon and only produce peak for 2-3 hours a day during the summer - 24 panels * 180 watts = 4320 watts peak production - in 12 hour days you would get 51840 watt hours in a. 12 hour day - but because the sun rises and sets you typically get about 40% of maximum production across the course of. day - so 24 180 watt panels will do 20'ish kWh's on sunny day…and 10 kWh's on a winter sunny day.

new panels are 280 - 320 watts - so the same 24 panels these days will do 7,680 watts peak production - 12 hours @ 7,680 would be 92,160 watt hours - discount by 40% and you should get 36,864 watt hours on a typical summer day and half that on a winter day. So a 24 panel install would produce 35 kWh's day 6 months of the year - or about 1 mega watt a month for spring/summer - and 1/2 mega watt a month for fall/winter.

or about 9 mega watts a year…

so it comes down to - how much power are you using? what is your annual bill - what is the approximate cost per kWh annually for all your power usage - and at $15-$30k install cost for a solar system when will you break even.

If you drive 60 miles a day in a bolt you're going to use 15-20 kWh's/day so add that to your bill and see if it all makes sense.
 

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PV experience

I have had residential PV for a decade and am now powering my second EV (ny first was a Leaf). My PV system is enormous compared to the usual residential system - mine is 10kW. Most are under 4kW. The annualized output of this 10 kW system in the SF bay area is a bit under 50 kWhrs per day. If you fully charge your car each day - you're talking over 100% of the output of a very large system just to power your car. If you're expecting to be able to "plug into your panels"...nope. It works in the summer when my system puts out upwards of 75kWHrs in a day, but not in the winter. Can you mitigate your travel by using solar - yep. Those numbers should give a reference point to make the financial calculations and evaluations. My own personal choice to do solar and to drive an electric vehicle is much more philosophical than it is monetary. I am determined to leave the planet without significant damage in my lifetime - a gift to my grandkids.
 

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David and I were posting at the same time. He has 48 panels @ 180 = 8.6 kW nominal. Mine is 44 panels 10.3 kW nominal. )I actually have 2 systems using a mix of 230 and 330w panels).
 

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I have a 4.94 kW system. We've had it for about 5 years now. We generate about 6500 kWH per year. Our PG&E bill went from an average of $250 a month to basically nothing but mandatory minimums now. In fact, the past couple of years we've had to walk away from un-used energy credits. I expect our bill won't go up much with the Bolt since we have un-used credits to start with, plus the manadatory bill minimums that also get applied to any usage first.
 

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I have had residential PV for a decade and am now powering my second EV (ny first was a Leaf). My PV system is enormous compared to the usual residential system - mine is 10kW. Most are under 4kW. The annualized output of this 10 kW system in the SF bay area is a bit under 50 kWhrs per day. If you fully charge your car each day - you're talking over 100% of the output of a very large system just to power your car. If you're expecting to be able to "plug into your panels"...nope. It works in the summer when my system puts out upwards of 75kWHrs in a day, but not in the winter. Can you mitigate your travel by using solar - yep. Those numbers should give a reference point to make the financial calculations and evaluations. My own personal choice to do solar and to drive an electric vehicle is much more philosophical than it is monetary. I am determined to leave the planet without significant damage in my lifetime - a gift to my grandkids.


i'm with you on that ... forget about the $avings ... it's about being green ... you drive electric, you produce your "own" electricity ... that completes the circle pretty good!


I have 28 panels and average 1 Me / months ... expect to pay $1k per panel installed before rebates/tax credits


don't wait around to long, many states/cities are working on changing inter-connect agreements that could negatively affect your finical benefit depending on how much you produce ... so make sure you get grandfathered in before that happens ...
 
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