[Jimbo69ny]

Hey guys,

Anyone here also into home energy? What are the good dc/ac inverter options out? EVTV has some for sale but they are $15k! Its hard to believe there arent cheaper and better options out yet.

I have a Tesla pack and I am looking to install an inverter so it can power my home.

 

[Jimbo69ny]

grid tied or not? non-grid tie is more diy friendly, just an inverter (some igbt and inductors and control logic). but grid tie you might be able to offset your existing bill.

Even if I was off grid solar, I'd still have some sort of generator handy, could even be the motor/generator out of an old prius or something that already makes enough bus voltage for the inverter.

edit, don't forget about mppt and battery management.

Hello Steve, thanks for your post. I am currently grid tied. From what I have heard, it is illegal to disengage from the grid in my area. I am not sure if its a nationwide thing or just shitty NY. I want to install a switch to go back and forth myself.

 

[Jimbo69ny]

If its illegal then fight to make it legal. In the mean time you can have one thing connected to show you use the power and then disconnect everything else. You end up paying a minimum bill to cover paper costs but it keeps you legal. Nothing illegal about having an OFF GRID system that does not connect to the GRID.

True, can you recommend an inverter that is designed for a whole house? I would have to check my breaker box but my guess is that I have at least 200 amp service. I live in the US so it is 240 volts.

My battery pack is made by Tesla with a peak voltage of 386 volts. The fuse on it is 350 amps.

 

[Jimbo69ny]

Here is my energy usage.

https://photos.app.goo.gl/G537nac4zDHbA5zr1

I dont have solar panels yet but I plan on adding them soon. When I do I want to add an electric hot water heater and range. Currently both are propane.

An auto switcher that goes back to the grid once my battery is used up is fine too. As to the comment about selling back to the grid, Id rather use it myself from my battery than sell it back to the grid. Follow me here, if I make the power and sell it to the grid they give us pennies, something like $.06 per kw. Then when I need it, they sell it to me for $.12 per kw. Why bother with that? I like Jack Rickard's idea of "selfish solar".

 

[Jimbo69ny]

Is that an external fuse that you added, or is that internal to the pack?

It seems like most of the internal Tesla fuses that we have seen posted have been rated ~650 Amps and the datasheet shows I2T ratings could handle 1500 Amps for ~20 seconds.

Has anyone ever read or heard of a tesla main pack fuse blowing during operation--i had never seen that reported over a couple of years while following the tesla club forum.

i'm interested in the home solar/inverter technologies also and in what you find will work.

It is the internal fuse. Rav4 EVs were detuned because its only front wheel drive. Its already a lot of power for the car as it is.

Yes I have heard of one Rav EV losing power on the highway due to a blown fuse.

 

[Jimbo69ny]

Hi Jim
That was your monthly usage

You need to get down and dirty and into your usage by the hour to see what you actually need!

On a monthly basis you used a maximum of just over 2 Kw continuous - but that does NOT tell you what you need

Get a piece of paper or a spreadsheet and walk around your house looking at what's on and writing down the usage at that time

Lay it out and think about it

Maybe you can lock certain high power usage items out - and only use them at certain times so they don't get used at the same time as some of the other high power devices

Charging the car
Electric cloths dryer
Electric Hobb
Electric heating

If you want to use an inverter with it's limited output you need to understand what you are doing

OR you can use a grid tie system like the one I have where the solar inverter just feeds the system and the grid is there to cope with any large power calls

Yes I do need to dig into it more. I dont have $15k for an inverter right now so it isnt a pressing task. I am interested to hear what you guys are using and how much you have spent. If it would only cost me a few thousand I might dive into it more.

 

[Jimbo69ny]

My inverter was about $2000 - 5Kw
But I have seen them for about $1500 - and that's NZD so about $1100 USD
So I would say that $15,000 is about a factor of 10 too high!

How do I know how large of an inverter I need? Add up everything that could possibly be on at the same time? Seems like that would make it artificially large.

 

[Jimbo69ny]

I dont have any shade where I plan to install. I dont currently have solar panels so that was all good info.

The last option of power flowing through the battery first wouldnt work for me because I also plan on using the battery for longer EV trips. I have the battery on a trailer and connect it to my car for longer distance road trips. But when I am home I would like to plug it in there to use to power the house. So the battery would have to be a removable part of the system.

If anyone has a page with products that you would recommend I would love to see them.