The 350 - 450V spec of the PowerWall tells me that this is simply just the battery, very similar to what is in the Tesla vehicles, only lower capacity and current. BMS must be included, but it looks like it is geared towards the typical grid-tie solar which has a 600V inverter and about 12 panels in a string, delivering around 400-500V. That DC voltage still needs the inverter to create 120 or 240V.
I spent only a few bucks to get something that has similar utility: I installed a 3kW inverter in my EV, so I can power select appliance in my home when the grid goes down by unplugging them and rolling out an extension cord to my EV. Not so fancy, but I am carrying my inverter (and my EV pack) everywhere, whereas the Powerwall is stationary. I am wondering how expensive the total solution (powerwall + inverter) is going to be and I am at a loss why only the battery is introduced, since you need the inverter to make it work... Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com Email: [email protected] Private: http://www.cvandewater.info Skype: cor_van_de_water XoIP: +31877841130 Tel: +1 408 383 7626 Tel: +91 (040)23117400 x203 -----Original Message----- From: EV on behalf of jim via EV Sent: Fri 5/1/2015 6:24 PM To: [email protected]; [email protected] Subject: Re: [EVDL] Tesla plugs into new market with home battery system Regarding possible life of a lead acid battery system, we are on our 3rd lead acid battery for our wind and solar home power system. First two batteries were used telephone company batteries and one of those suffered from broken cases rather than actual battery function failure. The second one was used for almost 12 years until we moved and decided to junk the battery rather than take the chance of moving it a few hundred miles. We made money as the salvage value had gone way up. Our current set was bought new in 1999 and is similar to a fork lift truck style of battery, 12 cells (2v each) at 1500 amp hours and cost about $4000 new. Today it might cost $5000 for the same thing. At 15 years old it is still going strong and I can't detect any loss of capacity, although we seldom discharge it below 80% and never below 50%. (and I haven't made any real accurate assessment of capacity) Tesla's battery is supposedly 350 to 450 volts, maybe 400 volts nominal (?) and appears to incompatible with anything that I currently own. I'm not excited about replacing charge controllers and inverters that are working perfectly well. Also I notice that the Tesla battery has a 2 kw output, 3.3kw surge, so a single battery wouldn't run a lot of things that my 4kw Trace inverter handles easily. So although the Tesla battery sounded interesting until I started learning details, I guess I will stick with my lead acid set up and my monthly battery checks and water additions. Maybe something more usable to my situation will be on the market in another 5 to 10 years when my lead acid set needs replacement. Jim, in western Wisconsin -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20150502/0d47233c/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/ms-tnef Size: 4756 bytes Desc: not available URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20150501/3100a5e1/attachment.bin> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
