My backup is a complete 85kWh pack from a 2014 Tesla Model S which is hooked to a 15kW split-phase inverter made by Bel (out of production), but with some crafty software on my controller I can go open my main breaker on the meter and turn on that system. It fires up the whole hose, then when (if) the sun comes out, my SMA 7.7kW grid-tie solar inverter "thinks" that the Bel inverter is the grid and begins pushing back into the Tesla battery. When the Tesla pack hits 85% SoC, my controller "burps" the AC by switching to 50hz for one cycle, then back to 60hz. This causes the SMA to disconnect and wait 5 minutes. It will keep repeating this until the SoC is below 85%. The controller is based on an ESP32 so it has a web page and will send out low SoC warnings to my phone. My house is heated/cooled by a LG multi-zone mini-split heat pump, so it runs fine on the off-grid system. I also still have the house's original natural gas furnace if needed, but I normally don't run it.
I told myself I'd automate this with a big 250A contactor on the main AC input, but it's a lot of expense/work and the power isn't out here but maybe a few times a year, and I can handle the manual switchover when it's needed. I have all my critical gear on a 2kVa off-line UPS hooked to a 48v 280Ah LFP bank, so that will stay up anyway. Picture of the Tesla pack in my workshop: https://ingineerix.com/pic/?tesla-super-powerwall Bel 15kW inverter: https://www.belfuse.com/product-detail/power-solutions-custom-value-added-solutions-emobility-350invch150-inverter-charger On Tue, Jan 16, 2024 at 6:13 PM Phil Hochstetler via EV <ev@lists.evdl.org> wrote: > Portland Oregon area just experienced a wind/cold event that took away > power from 150,000+. > I have a new in the box 7500 watt tri-fuel generator but had not set it up > yet (of course). > My model 3 was charged, but not setup with an inverter yet due to lack of > motivation, but our Rav4 Prime > had a full tank of gas and the 1500 watt built-in inverter that runs off > the high voltage pack. > I wired a short cord on the furnace (NG furnace) so we had heat as it was > 12F out and ran a cord into the house > under the garage door so we could run a light or two and the 2 burner > countertop induction stove and refrigerator. > Pretty sweet. In on mode (with doors locked with key), the rav4 would turn > on when the battery got low and recharge the battery. > After 24 hours, it used 1/8 tank of gas but we were warm and had > light/food. I went out and got 10 gal of gas to fire up the generator > and the power came on before I got back. Still fun. > > Phil Hochstetler > > On Mon, Jan 15, 2024 at 5:58 PM Mark E. Hanson via EV <ev@lists.evdl.org> > wrote: > > > Hi Folks, > > > > I was reading Otmar's inverter connection to a Tesla-3 and looks like > Tesla > > makes it really difficult to run a 1500W 12V inverter from their EVs. My > > Bolt shows 130A available from its DC-DC converter, just clamp the Harbor > > Fright inverter (have 1500W with 200A inline breaker, short aligator > > clamps) > > on the battery & the Leaf appears to be rated about 90A, so probably not > > enough to run my mini-split at 12A, 120V. Presently if the power goes > out > > - I just put another log in my wood stove, but thinking it would be nice > to > > run one of my EV's as the 64KWH power source incase the power goes out > for > > awhile. I have a Bergey wind turbine on LiFePO4 7KWH batteries, but that > > would only last a few hours running the Pioneer mini-split. Has anyone > > done > > this successfully? The Bolt has to be *on* in neutral or park with the > key > > in to keep the DC-DC converter alive. Would rather not have a Kerosun > for > > backup... > > > > Subject: Model 3 Inverter Power Connection - Otmar's Variety Blog > > > > > > > https://www.cafeelectric.com/blog/2020/06/08/inverter-power-connection-1/ > > > > > > > > Have a renewable energy day, > > > > Mark > > > > Mark E. Hanson > > 184 Vista Lane > > Fincastle, VA 24090 > > 540-473-1248 phone & FAX, 540-816-0812 cell > > REEVA: community service RE & EV project club > > Website: www.REEVAdiy.org (See Project Gallery) > > UL Certified PV Installer > > My RE&EV Circuits: www.EVDL.org/lib/mh > > REEVA Demo: http://youtu.be/4kqWn2H-rA0 > > Fincastle Solar Weather Station > > > > > > > > _______________________________________________ > > Address messages to ev@lists.evdl.org > > No other addresses in TO and CC fields > > HELP: http://www.evdl.org/help/ > > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20240116/6e56ff04/attachment.htm > > > _______________________________________________ > Address messages to ev@lists.evdl.org > No other addresses in TO and CC fields > HELP: http://www.evdl.org/help/ > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20240116/1d935d1b/attachment.htm> _______________________________________________ Address messages to ev@lists.evdl.org No other addresses in TO and CC fields HELP: http://www.evdl.org/help/
