Gas on to heat car - does it defeat the purpose

that's considering you have defrosted your windshield (because scraping it just refreezes the windshield) that's 6kw depleting the battery just sitting in your car waiting for the windshield to clear up

 

btw, Volt owners debate this topic as well. many want to have the option to force the ICE on for heating the cabin at the start of their commute. many have been using the remote start feature and pre-conditioning the cabin while it is still plugged into a charging station, that way they don't reduce the EV range as much by having to warm or cool the car immediately after unplugging.

 

the front windshield defroster is 1.4kw, it could run while the PiP is still plugged in on 110V and not reduce your EV range. Turning the heater on to HIGH is a beast, and 6kw is more than the PiP or Volt will draw from a L2 charger so it will draw down the EV range. I haven't gone through a winter with the Volt yet and my garage is insulated and winters are mild in Austin. If I needed to pre-condition I would probably have the heater set below HIGH and do a remote start 10 minutes before I wanted to leave and get the cabin toasty before unplugging. My summers are the challenge, with 110 days I pre-condition the cabin for 10 minutes before unplugging using the remote start from my phone.

 

that's the thing tho. the PIP doesn't have the option to stay plugged in and heat electrically

 

I'm sure (well, just guessing) the windshield defroster is electric. ok, maybe I'm thinking the rear window and the windshield is defrosted by the cabin heater.

 

ok, let's see the data

a cheap and dirty way to check is, see if your EV goes down when you turn on the front windshield defroster

of course in the summer, the A/C is used, which is electric

 

yea, but the A/C is relativly effecient compared to an electrical resistance heater.

 

agreed, what has Toyota optioned to do? heat from ICE? or A/C?

 

I don't think Toyota or GM are using the A/C for heating (a heat pump). Toyota is heating with the ICE and GM (Volt) is heating with both the ICE and electric, but electric while in EV mode, then ICE when it kicks into range extended mode.

 

Has anyone thought to contact Toyota to see what they say about this subject?

 

You are correct. The engine will at least have to idle.

However, it won't be the same as a cold start in the normal Prius because it'll only run it enough to provide the warmth. But then, since it's running anyway it will use the energy as best it can. I'd expect 0.02 gallons per hour, offset with reduced electric use.

As far as I understand it the small electric resistance heater is just to take the edge off any cold air coming in until the engine can provide enough heat.

 

I have not had a chance to read all the responses, but I am thinking cold winter is when the PiP may shine versus Volt and EV's. You would rather use gaso to supplement heat to interior rather than EV electrons. I am thinking if you want to put the heater on in a Volt, that may drop your MPGe down to as low as 20 MPG on a fossil fuel equivalent basis. So in winter PiP may acheive almost 2/3-rds as many EV miles as a Volt, due to the ability to use gaso engine to help on heat. Alternatively, the Volt driver is freezing his or her buns off to get good MPGe, but how much fun is that?

 

It gets so cold here that 10 minutes wouldn't warm the car (any car) anyways. For trips that short, I just keep the warm clothes on, and don't even bother with the heater.

 

Here is what I would say (but I don't own a PiP)
...if you do NOT plug in, the PiP has an EPA rating in the range of 50 MPG combined.
...if you DO plug in, you can get higher gasoline MPG, but that just means you have decided to switch over to electricity as your fuel source. Depending on your local elec costs and power plant fuel mix, fuel switching to elec may or may not cost less, and may or may not be any better than 50 MPG from a CO2 emissions perspective.

Hyper-miling techniques allow even better MPG and may help you manage battery charge.

 

The car gets about 100 miles on 34 kW of electricity, so you need extremely high electric rates before gasoline is cheaper. Most people pay around ten to twelve cents per kWh, some higher, some lower.

But even at 20 cents kWh, electric-powered PiP driving is still cheaper than gasoline, and hopefully few people pay that much for electricity.

 

Would that be a "high wear" event on the ICE? I have made an assumption, perhaps not a good one, that starting up the ICE contributes to engine wear, especially in the cold, albeit that not exercising the ICE for months has other consequences.

So what would be better .... exercising the ICE twice a day and getting some cabin heat, or not exercising the ICE for a month and using some of your daily excess EV range to heat the cabin? This question may not apply to the PiP since the notion of excess EV range is somewhat muted.

 

Sure, but engines are made to be started. The electric motor greatly reduces torque required of the engine at low starting speeds. But, at any rate, Prius engines aren't failure-prone. I've read through this board for two years -- I've seen people need battery, inverter, and transaxle replacements, but no engine replacements. I'm sure it's happened, but it's very rare.

 

I was thinking more about the frequency of needed oil changes rather than engine replacement. Does the PiP have a oil change indicator based on ICE usage or just vehicle mileage?

 

interesting you bring that up......since the ICE is not running most of the time, the mileage interval between oil changes would be higher, right?