You just have to do a calculation, What is the cost per KWH over the remaining life of the battery. A new power wall costs $6,700 and has 13 KWH that can be cycled daily for 10 years. so 3650 days times 13KW = 47 megawat hours for $6,700 or 14 cents per KWH.
DO the math on the used battery. If it is much less then $0.14/KWH buy it So if the price is $1,200 and it still can store 7,000 watt-hours and has a 5 year remaining life it would be useless in a car but it works out to $0.09/KWH and would not is a truly horrible deal. So it is possible a battery that is usless in the car could be used for a house. Better is to keep the battery in thr car and use the car for short trips, less than 100 miles. round trip Cell become usless in a car when you reach about 1/2 capasity but if the price per KWH is OK they can work in a house. FOr a house, you might need the cells for multiple salvage cars. On Sun, May 19, 2019 at 9:32 AM Dave Cole <linuxcncro...@gmail.com> wrote: > I do have to wonder though... if these Tesla cells were no longer usable > for a Tesla, why would anyone think they would be good in a stationary > application unless they were derated by quite a bit. > $1200 is far from free. > > Dave > > On 5/17/2019 12:24 PM, Kirk Wallace wrote: > > > > Here is a fairly common surplus Tesla module: > > > >> https://www.ebay.com/itm/262333679871 > > > > If these have have not been abused after they were removed from the > > car they should last many thousands of deep cycles. They are 6s but a > > 7th s can be added in order to cycle them deeper on a common 24 volt > > system. > > > > My system (single, living in an RV) is close to this except I am using > > two Johnson Controls modules rewired as 7s: > >> https://www.mobile-solarpower.com/tesla-solar-battery-diy.html > >> https://www.ebay.com/itm/123187038180 > > > > This technology is changing so quickly that it is hard to keep current > > and reviews become stale in a month or two. > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
