I am charging at 25A vs 48A. I drive less than 20 miles per day so I am using roughly 10kwh. Yes it is half as fast as my wall charger but I am asleep while it charges. This setup was also to have additional power when the power goes out and not buy a standby generator.How long does it take to charge your S and what’s your starting SOC?
I have 30 panels for 12kW of power and at peak sun, output just over 9kW. My 240v portable charger (not Rivian) consumes 8.9kW of that and will charge my S at around 30 miles of range per hour.
That means my system provides 18kW in 2 hours to my S. I can’t imagine yours is capable of charging your S from this array, but surprise me.
Nice.This was more of a science experiment but I added 10- 400 watt panels, eg4 6000xp, and eg4 14kw battery. Two days in and I am maxing out the battery which provides enough charge for the car. In total the project cost about $8k, so a 15 year payback.
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My girlfriend drives a M3 and I could up the R1S charge to 85%. I have not figured out what to do when I am out of town. I may just turn the system off. Or I could add a transfer switch and run the house.What do you do with the extra electrons that don't fit in your EV? Assuming it's standalone and doesn't feed into your home.
I wish payback was that good. I am at .12/kwh. So about 600/year. But it beats paying $600/year on a service contract for a standby generator.Nice.
You should be able to get 15 to 20 kWh per day out of that. Depending on your cost of electricity that would be about $5/day so about $1500 to $2000 a year if you use it every day.
That's about 40 miles of driving a day which is more than average.
Good design.
I have a 70 year old roof and I know it’s only a matter of time before I need to replace. At that point I will add whole home. I could fit a 12kw system and I can now save about $10k as my off-grid has battery backup.$8k on a standalone EV charger? My home rate is $.05-$.10KW it would take 107MWH to break even. Better to spend more on a whole home solar setup.
I am very interested in your setup. I have been considering something similar and would like to know more details of what and how you did your project, if you would be willing to share. I elected to not do whole house generator for same reasons you mentioned.This was more of a science experiment but I added 10- 400 watt panels, eg4 6000xp, and eg4 14kw battery. Two days in and I am maxing out the battery which provides enough charge for the car. In total the project cost about $8k, so a 15 year payback.
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If you're paying for install it's going to be usually 3x the material cost (that's average contractor rule of thumb), maybe more for solar since most everyone jacked up prices with the tax rebates. Panels themselves are less than $1/watt (sometimes way less) and being not grid-tied saves a bit of complexity.How the heck did that whole system cost only 8k? All the estimates I've found for getting solar on my home (maybe 14 panels?) comes to at least 30-40k, and that doesn't include battery backup...
10 panels - 1kI am very interested in your setup. I have been considering something similar and would like to know more details of what and how you did your project, if you would be willing to share. I elected to not do whole house generator for same reasons you mentioned.
Thanks.10 panels - 1k
6000xp - 1500
Battery - 3500
Parts/materials/labor - 2000
I could have bought a bigger inverter but I knew I would not exceed 6000 watts on this off-grid setup. Also I am only charging at 25A so I am ok with the slower charging. All in all this set is sufficient if you drive less than 40 miles/day.