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Old 07-10-2021, 07:48 PM   #9
FlyingScot
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Quote:
Originally Posted by mswlogo View Post
My point was, he HAS a generator.

I have solar in MA. I love it. But I have absolutely no need for a battery because it is NOT viable. Period. Because I have net metering. The grid is my battery. I plan to have solar in NH too.

I also have a Tesla and a Volt and produce enough Solar to cover both cars and the house and enough credits to cover the electric bill in NH. Basically I pay zero for any fuel. This isn’t about that.

It’s the assumption a car battery can be your sole source of backup power in the event of a long power outage. Quite simply it sucks at that task.

What people don’t get is Solar works based on averages. On average, year round you can generate enough power to run your house. If you can store the excess you generate in the summer and use that excess you produced in the winter. You can’t depend on it, on some schedule.

There is no battery big enough to store summer over production for winter. Except the “virtual battery” ( called the grid with net metering).

Now you can use a battery to collect solar during the day and use it for the rest of the day when sun is gone. But often during peak (over) production you still won’t use it all. It’s only during certain parts of the year it works. Hate to clue you, batteries are wicked expensive. So you have to have huge savings to cover their cost. You won’t save that much in MA or NH because Net Metering is WAY better than a battery.

For power backup. A modest generator (~$1000) can do what the Ford truck can do. And it’s more reliable because you’d have some reserve of fuel for it (not guaranteed with an EV). The OP already has a 7kw generator. A ford truck buys him very little in term of added power security. The generator is probably his best insurance.

What if you just came home from a long trip and the battery is at 20% and you lose power. Or What if you lose power for a couple weeks (like was suggested). You are screwed. Chances of that are probably low, but it can happen.

You can’t depend on Solar. It’s usually there, but sometimes it’s not. And there is a whole lot less of it winter and much more common streaks of low output. I clean my panels in winter. Pretty stupid move actually. I probably gain $2.00 of energy for 1hr of work and risking damaging my panels. Smart people leave them alone. They can easily be covered with snow and ice for a solid month.

If you wanna go that route, for backup, go for it.

I have Solar. It’s doing great and have no regrets. But if I put that money into the stock market. I’d be in about the same shape. I’ll break even in about 6 years. That means my $30K I spent will be covered. But I end up with a Solar System now worth say $20k (because it’s 6 years older). If I put $30K in an S&P index fund that earns roughly 10.5% compounded. Then my $30K would be $50K. 2X Stock market, I don’t think so. Perhaps if your a bad investor.

Curious what EV’s you own and what you have for Solar? And how your numbers look.
I own a Tesla S and 18kWp of solar on my Mass house. Returns on my home solar are better than 15% IRR.

When we think about the return on solar compared to the stock market, it is important to keep in mind that the past ten years or so have been extraordinary for the stock market, and the stock market is much more risky than solar, which is similar to a bond in terms of risk. On a risk-adjusted basis, solar is much better than stocks. If your retirement portfolio is 60/40 stocks/bonds, you'd do really well to sell some bonds and put the money into solar on your roof.

Nobody has asserted the Lightning should be your only backup if your power is unreliable or that battery backup is a driver for either solar or EVs. But it would be a great feature for those (like me) who do not own a generator. So it's kind of weird that a Tesla driver would throw so much shade Ford's way
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