Prius Plug-in Hybrid Update

My point is that it is a matter of perspective. To me it is a bit silly to compare the PiP to other *EVs through a "pure EV miles" lens. It obviously is the bottom of the barrel.

As a petrol car that beats the pants off even a Prius however, it is outstanding. Yes, you do have to plug it in.

 

Now if that's the case then that would make a significant difference for me.

Yes, that is my opinion. However, getting the EV miles up over 20 would close that gap considerably, at least for me.

 

every consumer will make an ev choice based on ev range, or range and mpg. it's not like buying a gasser. the pip is appropriate for some, the volt for some, leaf, tesla, etc. the more variety, the more people will be drawn into the circle. but there is always a tradeoff for more ev miles.

 

Yep. And be outfitted with an ~ 7 kWh battery of which some 5 kWh is usable.

 

Yup. Not knocking some of the other choices and indeed 50 miles of EV range with 40mpg will work well for a large number of people.

But a PiP with 20-25mi EV range and 55mpg is a better bet for many. 20-25mi EV fits many commutes. If, like me, 50% of miles are road trips way beyond EV range, the PiP will use considerably less gas. Plus there is better seating and room for cargo...

 

and then i think, it's not really cost effective to buy a phev to cover x% of your driving in ev, and a whole hybrid system too.

 

It has always been silly to argue which EV range is 'best.'
People match the car to their driving patterns.

And while some consumers choose a car that makes most of their days 'EV,' I am more interested in reducing my overall liquid fuel consumption.

 

that can be a complicated equation for many people. there needs to be a sticker with simplified graph of average driving habits and how much that vehicle will reuse your consumption.

 

Average is pretty useless. It is definitely very inefficient.

As for complicated, that is why we have calculators. Arithmetic can be difficult ...

 

Adding longer ev range does this to your hybrid; a difference of 4mpg: Compare Side-by-Side

 

A valid choice depending on your commute and EV ratio desire.

The efficiency of EV mile would decline as the pack gets bigger.

I think it is important for EV miles not to exceed gas emission. 80 MPGe EV mile is about as clean as 40 MPG gas.

100 MPGe vs 50 MPG gas
110 MPGe vs 55 MPG gas
120 MPGe vs 60 MPG gas

Etc. I hope EPA comes up with emission profile that can easily compare EV and gas miles.

My 2012 PiP is got 148 MPGe on EV and 61 MPG on gas on the last tank. EPA failed miserably at their rating as it predicted 95 MPGe (combined) without EV and gas efficiency breakdown.

 

Hi Dennis,

How is that ratio derived ? By my arithmetic it only holds if most of the marginal fossil fuel use is natural gas.

Calc:
According to CleanTechnica NG burned at the plant has 469 grams of CO2 carbon intensity per kWh at the 50th percentile.
7% of energy is lost by transmission. So a kWh in the battery lead to 469 * (1/0.93) = 504 grams of CO2 emissions.

An MPGe is 33.4 kWh, so 40 MPGe miles would consume 16.7 kWh,
and lead to emissions of 16.7*0.504 = 8.42 Kg of CO2, equal to 18.5 lbs.

A gallon of combusted petrol is about 1.2 gallons of oil, so 24 lbs of CO2 emitted.

If we presume marginal electricity is 50% NG and 50% coal then a generated kWh = 0.5 * (469+1001) = 735 grams CO2/kWh and therefore 735/0.93 = 790 grams at the wall. The 16.7 kWh used to travel 40 miles then has emissions of 16.7*0.735*2.2 = 27 pounds.

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By my numbers, an 80 MPGe EV fueled from the 'grid' is about equal to a 36 MPG petrol car.

 

From "Beyond Tailpipe Emission" site last I checked. As a reference, 100 MPGe is as clean as 50 MPG hybrid. This is using Us grid average weighted by kWh.

 

Do they show the calc ?

I added mine to my earlier post

Addendum: I looked at the website you mentioned. It shows 'national average' emissions as 220 grams per mile for a LEAF rated as 114 MPGe. So an 80 MPGe vehicle would have associated emissions of 313.5 grams per mile.
Over 40 miles that is 40*0.3135*2.2 = 27.588 lbs CO2

The 40 MPG petrol car is 24 lbs CO2 per 40 miles.

The plug-in has a bigger petrol tank but goes a shorter distance than the hybrid.

 

Perhaps on one of their more technical sites.
Beyond Tailpipe Emissions

It uses the average grid mix from 2007 or 2009. So the higher percentage of coal means more CO2 per kW.

The Energi has a different gear ratio for the EV mode.

 

One more data point, from a 2015 paper by CMU:

And weighs more I presume, which I think is more to the point.

 

Grid got cleaner and they updated to reflect that. Noted mentally, 115 MPGe = 50 MPG.

 

right, but i think most of us have typical drives. work, school, errands, friends and relatives. looking at theses distances would help the consumer to make an informed choice, especially when combined with epa data that's dumbed down to the likes of me.

 

Work can be anywhere from 3 - 100 miles away. Relatives, next door or across the country. The SD is huge.

I was thinking about the driving my household does:

• 5 days a week between one and two trips a day of 10 miles each trip
• 2 trips a week of 90 miles each r/t trip to work. Presently no charging offered at work
• During this summer a 500 mile r/t to Albuquerque twice a month. I could charge every 250 miles

Forget the calculator. America needs a spreadsheet.

 

i mean each individual needs a form to fill out with their typical driving habits, not the average for the whole country. if that were the case, we'd only need one drive train and multiple looks.