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Comment by malfist | Hacker News Reader

To put it in perspective why a 5kWh generator isn't a range extender: my lightening has a range of 331 miles and 135kWh battery. If we assume a spherical cow (60mph, and I get every single one of those 331 miles), the truck buns through the battery in 5.5 hours, which equates to 24.5kWh to keep up.

In actuality, at highway speeds I'll burn through 80% of the battery in 3 hours which equals a run rate of 36kWh. If we ran a 5kWh generator the whole time and assume perfect charging efficiency, it'd extend the time to charge by 28 minutes.

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My Chevrolet Bolt actually shows me the real-time kW draw from the high voltage battery and, while it's highly dependent on driving conditions, it seems to require around 12-15 kW to maintain 60 MPH on a flat dry road using cruise control and with the climate control turned off. It's not the most efficient model on the market, but it's also far from the least; as you noted your F-150 would need significantly more energy under the same conditions.

The lightning is ridiculous, it weight 70% more than your bolt and is huge.

My partner and I honestly bought it to be a whole house backup battery. My regions get ice storms and we have hundreds of gallons of aquariums we'd need to keep powered through a long duration power outage. 135 kwh of battery storage cost more than the 135kwh battery truck, so we got a whole house battery backup system with wheels and cruise control. It can backstop 80 amps for 3 days.

If it were me I'd just get a whole house generator in that situation, seems like it would be a lot less than the truck with batteries or the batteries. The bonuses are I wouldn't need to replace an expensive truck with another expensive truck in the future if I didn't want to. 3 days is impressive, but I had an ice storm leave my family without power for 3 weeks once.

It's pretty strange that 135kwh of stationary batteries are more expensive than 135kwh with a truck attached, seems like some one must be running a screw job on the storage batteries.

Regulations!

We've had pretty poor experiences with generators in the past. A whole house generator is very expensive, especially with a transfer switch. Without a transfer switch you have to run the generator outside and route power inside through a window left ajar, which is not great when the ice storm has happened. The truck is parked in an insulated garage and is easy to route power from.

3 days is impressive if you're pulling maximum you can from the truck, if you pull anything less than that your time is greater. Our aquariums do not require all 80 amps. Max length power outage for us has been a week and the truck will easily last that long.

And totally agree about the cost of battery power banks. This was a few years ago, so things might be different now.

You can't drive the truck during that week? So you need to keep a spare car for the time your battery bank isn't mobile?

Rather, for all the other time when the power is working, you can use your generator for transportation!

I don't know about you, but I'm not driving very much during or after an ice storm.

Besides, the aquariums are fine without power for an hour or three, so technically I could if needed.

For what it's worth you get fairly similar results if you assume an efficiency for a ICE engine (25-40% depending on a lot of things) and work backwards from the energy density of the fuel and the milage you achieve over a trip.

But charging at the service station will take 20 minutes after a 3 hour drive which seems reasonable

We did a 12 hour driving trip just recently. Did 15-20 minute breaks for charging about every 2 hours. Perfect timing to get out, use the bathroom, get a new beverage and get going. Barely felt like we were stopping to charge anywhere except when walking to the bathroom since chargers tend to be on the edges of a parking lot instead of near the entrance.

As a bonus, Ford pushed out an update last year that allowed the truck to charge at 185kws for the first 15 minutes or so of a charge before things heat up, so we took full advantage of it. By the time the charge rate was slowing down we were unplugging to go.

I think you mean kw. The kWh rating is basically just how big the gas tank is.

Technically correct for the rating of the generator output capacity, I was just meeting OP where they were at and they used kwh as a unit for the generator. At the end of the day, that nuance isn't all that important

Using the right units is definitely important. I don't know why we've just decided they don't matter in this regard.

that's kind of like saying you have a 500 horsepower gas tank, or a 10 gallon engine, though.

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