Poor And I Mean Poor Mpg, And Tyre Pressures In Winter Tyres

[Joseph D]

Nooooooo! Let me clarify: The point of being able to force the car to run on the diesel ICE only is so you can pre-charge the battery as much as possible. When you get to a NEZ, you then have the maximum charge available to run on electric only for the maximum amount of time.

With the HSDs, you have no control over the battery charge so even if you know you are heading into a NEZ, you can't tell the car to keep running on the ICE and charge the battery as much as possible so you might end up in the NEZ with only 1 mile of charge left, at which point the ICE will kick in to charge the battery.

I do understand what you are saying - it would be nice to drive in a NEZ for as long as possible on electric, but putting aside the efficiency for the moment, by pre-charging with the ICE you are just shifting the pollution problem from within the NEZ to outside it, so the net effect is no change to the overall level of pollution.

From my experience HSDs do a damn fine job of managing the HV SoC, and yes, it is annoying arriving at a point with a lower SoC than you would like, but if that is the case the the preceding terrain has been such that there was little opportunity to syphon off any excess energy to the store in the Battery. C'est la vie.

I can't believe you don't see the huge advantage of being able to pre-charge the battery - I guess I'm just not very good at getting my explanation across :(

It's not that I don't see it, believe me I do, It's just I do not agree with you. Like I said you are just shifting the location of the pollution problem.

If you'll forgive me for using hills in the example again; It would surely be more efficient to extract charge for the battery while cruising on a flat motorway rather than while trying to climb said hill where you really want the ICE AND leccy motor working together instead of loading everything on the ICE?

Again, from my experience of the HSD, this is exactly what it will do, if it can, so there is no need for a manual override. Again, I would say it actually goes counter to the objectives of lower emissions and higher fuel economy. Both will take a hit. The only thing in favour is to move the move pollution problem from A to B.

If you are aware of the impending situation, you can prepare, adapt and optimize for it - This is what a good driver does, and being given the ability and tools to do so can surely only make a good driver better rather than everything being dumbed down.

When you see how intricately the computers (which have been programmed to contain a high level of knowledge from years of R&D) are juggling the ICE and MGs second by second to provide the best combination of efficiency and fuel economy, I do not think it is humanly possible to do better over the long run. I do not think it is a case of being dumbed down, more boxing up the cleverness and distributing to the masses. When you understand that the HSD could not work but for the speed and precise control of computers, I dare say it'd be a very clever person to do it manually. Yes, I do sound a little fanatical, but I have owned a Prius for over 8 years now and I'm still amazed at how it all works together.

I'm not sure what point you're trying to make about the efficiency of charging the battery via the ICE vs regeneration tho' - Ignoring the energy from the plug-in side of things, ALL the energy in the battery comes from the ICE in a hybrid. Where do you think the regeneration energy comes from? Momentum which, ultimately, comes from the ICE! And yes you get energy back from going down hills, but I guarantee you it is nowhere near the amount of energy you expended climbing up the hill in the first place with, yes, the ICE!

The main reason hybrids are more efficient is that they recapture energy that would otherwise be lost, but that energy still comes from the ICE in the first place - It doesn't magically come from thin air! With the plug-ins you do get some from the grid too, but that is a tiny fraction compared to the total potential energy you get from the ICE.

You are absolutely correct and I concede that point, all the HV energy is ultimately generated at a loss from the ICE. You are right again in that hybrids are more efficient in that they recapture energy that would otherwise be lost and also that the energy does not magically come from thin air. You'd be a rich person if you could make that happen! :) However, the amount of energy recouped vs expended can be better in one scenario over another. For example, I know from experience that if i start at an altitude, go up and over a hill back to the same altitude on the other side, that, if one direction, I climb more steeply up and then descend at a more gentle gradient down, I will recoupe more energy on the downside of the journey out, compared to the journey back. I guess that is what I was trying to get at, albeit a little clumsily.

[Grumpy Cabbie]

The PIP has an option to force the engine on doesn't it? Or at least not use your charge until you get to the city.

I think the Prius hybrid and the plug in Prius are being mixed up and compared to the plug in Volvo.

The traditional Prius is a petrol car with electric assistance (sort of, but I'm keeping it simple).

The Plug In Prius and the super expensive Volvo plug in both need charging up at home to go about 10/30 miles on electric and the remaining time on their respective fuels.

Personally think these plug in cars are way too expensive for their own good. The Volvo is about £45,000. I'd pay another £5,000 and get the Tesla and never have to go to a filling station ever again.

[kithmo]

The reason why I chose the 15's on mine or one of the reasons for the t3. Much more forgiving on curbs ;)

Funny you should say that, but it doesn't seem to make a difference with the Prius.

I kerbed the Gen 3 rear wheel (145 45 17") on a corner kerb and the tyre actually contacted the kerb without touching the rim.

lol you weren't going fast enough ;)

I'll go and have another run at it with the +

[aCactus]

The PIP has an option to force the engine on doesn't it?

I've not found that option - there is a HV/EV switch which only works if you have suffiecient charge in the Battery to run in EV mode otherwise you just have a "normal" hybrid.

With the recent colder weather and having heating on and heated seats during my usual short journeys my car is using the ICE more and as a result is slowly charging the traction Battery.

[Grumpy Cabbie]

The PIP has an option to force the engine on doesn't it?

I've not found that option - there is a HV/EV switch which only works if you have suffiecient charge in the Battery to run in EV mode otherwise you just have a "normal" hybrid.

With the recent colder weather and having heating on and heated seats during my usual short journeys my car is using the ICE more and as a result is slowly charging the traction Battery.

You'll know more than me. Doesn't the PIP have a 'hold' function which holds the ev range for later? If it doesnt, it was going to.

I was after a PIP until Toyota UK priced and specced it the way they did. The US market has a 'normal' spec AND the fully loaded spec like the UK. As such, the lower one is much much more affordable and priced about the same as the UK t4 spec. Far from £32k before incentive :)

[aCactus]

The HV/EV switch is al there is (plus an extra ECO switch). By selecting HV (which I do most of the time as the car defaults to EV) I found during the "Summer" that the main Battery gradually lost charge - opposite to what it is now doing. I suppose that means in Spring & Autumn that means HV mode is a "hold" function.