But why are you so determined to use batteies when the cost of grid power is ditrt cheap.
a 1kwh deep cycle lead acid battery might cost $100. It will store 10 cents of electricity per day. After one year it is SHOT. that is $100/365 days or about 27 cents per kWh. So you are paying TRIPLE the cost of electricity just for a battery compared to just getting it from the grid? And this does not even mention the cost of solar panels. This is purely battery storage costs. Even if you find magic battteries that can do 1000 discharges before replacement, that still is 10 cents per kWh storage cost and still does not even count the cost of solar to get the energy inthe first place. AND, unless you do a full cycle of thebattery everyday, to use y our incoming solar, then you are not fully using your array.investment. Sure you can throw away all kinds of money at this problem, but nothing canbeat being grid-tied and a net meter. Just do it. Do a small system at contractor prices... then add panels at your leisure and at 20% of the cost. bob On Sun, Jul 14, 2019 at 10:50 AM Peri Hartman via EV <ev@lists.evdl.org> wrote: > Actually, I am proposing something simpler than a power wall - that does > not feed back to the grid. Maybe that simplification doesn't reduce the > cost of the battery system much, but it would reduce the legal paper > work down to a normal electrical permit. > > Peri > > ------ Original Message ------ > From: "Willie via EV" <ev@lists.evdl.org> > To: ev@lists.evdl.org > Cc: "Willie" <wmckem...@gmail.com> > Sent: 14-Jul-19 7:30:58 AM > Subject: Re: [EVDL] Solar off grid with an EV? (transformers) > > > > > > >On 7/14/19 9:06 AM, Peri Hartman via EV wrote: > >>How hard would it be to build a battery system that normally supplies > 100% of the domestic power but, when depleted, switches over to supply > domestic power from the grid ? Also, I think it would be safe assumption, > or at least a reasonable simplification, to assume that the battery is > always sufficient for the load, except when depleted. The battery would > always be charging from a solar array, never from the grid. > >> > >>It seems to me, a system like this would completely circumvent any > negative conditions imposed by power companies. Of course, once the solar > panels fill the battery, excess production is lost. > > > >You have described a PowerWall. The battery is one or more units that > will supply or charge 5kw and holds 13-14kwh. If about 11kwh will carry > you over night and if you don't use more than 5kw over night, a single > battery unit will serve you. With good sun, day time self power use can be > around 20kw, including car charging. > > > >In 5 or so months, I have bought less than 10kwh from my utility and sold > them something like 10,000 kwh. That is with one battery unit. > > > >Cost installed was about $13k. For smooth operation, I am highly > dependent on the utility to accept my excess power. > > > >_______________________________________________ > >UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > >http://lists.evdl.org/listinfo.cgi/ev-evdl.org > >Please discuss EV drag racing at NEDRA ( > http://groups.yahoo.com/group/NEDRA) > > > > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > Please discuss EV drag racing at NEDRA ( > http://groups.yahoo.com/group/NEDRA) > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20190714/9cbd7158/attachment.html> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
