Revisiting small 12v heater discussion

Two things here; I agree that further gains may theoretically be possible (watch for the Gen 4) but I don't have the engineering skills (the numbers) to achieve it, and I question anyone who thinks it's just as simple as running the engine for shorter times. We simply have to assume that Toyota knows what they're doing.

Exactly.

 

i think this discussion is somewhat polluted by a lift back mindset. i would love to find out more about the 600w heater. that's half my wifes blow dryer on low, and you that that would be detectable inside a car at 20 degrees.

 

Maybe you would; maybe I would, but the point is that Toyota made the judgment call. Is it possible that the electric-heater idea may have a fatal-flaw that you may have overlooked?

I'm no engineer, but I know it takes a lot of watts to blow a small amount of warm air.

 

As Chap says, lots of ways to come out ahead, depending on the circumstance. Consider mine:

• I do not want to use the usual cabin heating in my (v)agon for the first 10 minutes of a drive on a cold winter day. The advantage to me is quicker ICE warm-up which lets me P&G and brings the ICE up to efficient operating temperatures earlier**. A 40 watt blanket for 10 minutes costs me under 7 Wh of electricity, which is about 0.00060 gallons* of fuel.

GREAT DEAL

*Assuming 36% thermo efficiency of the ICE, paid back when the engine is nice and warm.
** Figure a 5 minute savings of driving at 50 mpg rather than 25 mpg. If the 5 minutes is 2.5 miles, the fuel savings is 0.5*2.5/50 = 0.025 gallons.

 

Value choice. If you want to forego interior heat for a few cents off your fuel costs, and that gives you satisfaction, you apparently win both ways.

Personally, I choose to consider the bigger picture, and it's not worth all the agonizing over small things for small potential gains. I derive more satisfaction from driving a vehicle which was designed to be more efficient under normal driving.

 

Correct -- value choice.
The engineering and physics, however, are pretty straightforward.

 

You can't argue with the economics of a bicycle, either. You can always trade comfort for economics; you don't need engineering or physics for that.

 

We are not discussing bicycles, we are discussing use of electric heat rather than ICE heat.

 

But that's the logical endpoint of your argument. At some point, it looks like a lot of time, expense and discomfort just to save a little bit of fuel.

My Dad always said, "Why spend $10 to save $1?"

 

it costs me nothing to not turn the heat on, and you can take that to the bank.

 

And it costs me less (in pollution, money etc) when I use less. Isn't that amazing ?

 

it's complicated, but worth the effort.

 

It costs much less to ride a bicycle.

 

your insight amazes me.

 

It keeps me from being distracted from the bigger things by the tiny things.

 

Another value judgement.

Lots of PiP owners, Bisco included, wonder why they paid thousands of dollars for a plug-in when the damn ICE runs for short winter trips.
I am happy to save small amounts: they add up. If they were multiplied by the 100s of millions of people who have a choice, they would be huge amounts.

 

all i have is tiny things.

 

I think PiP has electric heating element. I have seen ICE running for heat and a battery pip dropped. So it was using both for heat.

Co-generation is what allows PiP to be so efficient with either fuels. A regular Prius (rated 50 MPG) turns on ICE for heat and PiP is no exception.

Yes, short trips that need heat stinks. But how often do you really run into those?

Using electricity for heat is also a bad idea, especially from the battery.

 

Oh! So sorry!