The Lemon Fool

i took a test drive today in the 1.3l dig-t turbo cvt automatic - 157 bhp.

very nice quiet smooth drive , loads of power , plenty of space for us , should be a very good car if nissan have overcome the reliability issues (mostly dud starter batteries ) that plagued to 2016 version.

what puzzles me is it never runs on the battery alone , the petrol engine is always running .

the salesman said the (lithium) battery complements the engine during acceleration .

so what is the point of such cars as regards climate change - DAK ?

I think it basically makes it a bit more economical, by recovering energy into the battery during deceleration. This is then later (re)used to assist the petrol engine.

So some decrease in fuel consumption (therefore CO2 emission).

Scott.

In theory energy that is typically wasted as you brake for the traffic lights is stored in a small battery sand then released to help you pull away again when the lights change. this leads to less fuel usage and less CO2s being released into the atmosphere.
However the battery in this case is so small the saving are marginal, Nissan are claiming "up to 4g/km" savings, this is for a car that has a typical output of around 140gm/km so minimal savings in the real world one would think.
Smells of Green Wash to me.

swill453 wrote:I think it basically makes it a bit more economical, by recovering energy into the battery during deceleration. This is then later (re)used to assist the petrol engine.

So some decrease in fuel consumption (therefore CO2 emission).

Scott.

===========================

yes , i can see there would be some advantage there , but would that outweigh the significant extra weight permanently pulled around - ie the lithium battery , electric motor and transmission shafts etc ?

jackdaww wrote:so what is the point of such cars as regards climate change - DAK ?

It helps the car meet the latest emission standards, but as it uses a cheap 12v system not the more expensive 48v system then it meets the ‘price point’ Nissan and their customers want.

PhaseThree wrote:In theory energy that is typically wasted as you brake for the traffic lights is stored in a small battery sand then released to help you pull away again when the lights change. this leads to less fuel usage and less CO2s being released into the atmosphere.
However the battery in this case is so small the saving are marginal, Nissan are claiming "up to 4g/km" savings, this is for a car that has a typical output of around 140gm/km so minimal savings in the real world one would think.
Smells of Green Wash to me.

4/140 is about 3%. Over the last 50 years there have been a lot of similar small improvements in fuel economy. As an automotive engineer if you can pick up a little bit and the cost* is not too great you go for it, and then look for the next 1%. It all adds up. The consumer is better off looking at the overall characteristics of the car, instead of particular details of the valve timing or electrical system or how much sloping the A pillar another degree reduces drag.

The marketing department may end up hyping relatively insignificant details. It's what they do. Ignore them or accuse them of Green Wash if you like.

* Costs include warranty costs and reputational cost. Engineers pay attention to things lasting the life of the car or being a service item. They sometimes get it wrong, but they do try.

PhaseThree wrote:In theory energy that is typically wasted as you brake for the traffic lights is stored in a small battery sand then released to help you pull away again when the lights change. this leads to less fuel usage and less CO2s being released into the atmosphere.
However the battery in this case is so small the saving are marginal, Nissan are claiming "up to 4g/km" savings, this is for a car that has a typical output of around 140gm/km so minimal savings in the real world one would think.
Smells of Green Wash to me.

=========================

" UP TO " -- usually under ideal circumstances .

more likely to be around half that in practice.

every little helps , but arent hybrids being sold as a major upgrade ?

nissan are bring out their " E-PWOWER " qashqai model next year .

it is totally different .

a petrol engine drives a generator which charges a battery which supplies a motor driving the wheels .

since all the power comes from the petrol engine , i can not see any significant advantage for global warming .

same applies to pure EV's , until the national grid is very substantially upgraded to carry mostly renewable power .

jackdaww wrote:every little helps , but arent hybrids being sold as a major upgrade ?

No, up to now hybrids were mostly sold to company car drivers for the lower tax due to the way they could legally 'cheat' the emissions test.

For the future hybrids are a dead end in mass market cars.

jackdaww wrote:same applies to pure EV's , until the national grid is very substantially upgraded to carry mostly renewable power .

Fossil fuel is the minority fuel source for UK electricity production, which is around 40% renewable, 40% fossil fuel, and 20% nuclear.

PhaseThree wrote:However the battery in this case is so small the saving are marginal, Nissan are claiming "up to 4g/km" savings, this is for a car that has a typical output of around 140gm/km so minimal savings in the real world one would think.
Smells of Green Wash to me.

That's €380 a vehicle in reduced emission fines in Europe, or upwards of €80,000,000 a year minus costs. System weighs 22kg.

jackdaww wrote:a petrol engine drives a generator which charges a battery which supplies a motor driving the wheels .

since all the power comes from the petrol engine , i can not see any significant advantage for global warming .

The advantage is that the petrol engine is kept constantly at its most optimally fuel-efficient output level. No wasteful bursts of acceleration, no excessive fuel-guzzling at high speeds. And the energy is then stored for release through the highly efficient electric motors. The same principle, in fact, as a diesel-electric locomotive.

BJ

9873210 wrote:

PhaseThree wrote:In theory energy that is typically wasted as you brake for the traffic lights is stored in a small battery sand then released to help you pull away again when the lights change. this leads to less fuel usage and less CO2s being released into the atmosphere.
However the battery in this case is so small the saving are marginal, Nissan are claiming "up to 4g/km" savings, this is for a car that has a typical output of around 140gm/km so minimal savings in the real world one would think.
Smells of Green Wash to me.

4/140 is about 3%. Over the last 50 years there have been a lot of similar small improvements in fuel economy. As an automotive engineer if you can pick up a little bit and the cost* is not too great you go for it, and then look for the next 1%. It all adds up. The consumer is better off looking at the overall characteristics of the car, instead of particular details of the valve timing or electrical system or how much sloping the A pillar another degree reduces drag.

The marketing department may end up hyping relatively insignificant details. It's what they do. Ignore them or accuse them of Green Wash if you like.

* Costs include warranty costs and reputational cost. Engineers pay attention to things lasting the life of the car or being a service item. They sometimes get it wrong, but they do try.

Full disclosure - I have worked in the automotive industry for the last quarter century primarily as a chip designer supplying the majority of the Europen car industry. I would like to think that the teams I have worked in have been at least partially responsible for the incremental gains seen in CO2 reduction in this time period.
What I do know is that just about every other manufacturer has decided to use 48V systems for their mild hybrid offerings (Think BMW, Merc, Ford, VW group, Kia,Volvo etc) and see/quote an average of 15% improvement. It may be that the engineers at Nissan have managed to engineer their 12V mild hybrid system in such a way that they can extract useful gains from such a system. Personally I would expect the torque generated to be too small to be of much use and the real world gains to be minimal. Unfortunately such gains are notoriously hard to measure in real conditions.
So why would anyone fit a feeble hybrid system to their latest and greatest automotive product ? The answer is unfortunately that the majority of the public will see the Hybrid logo on the back and look no further.

AF62 wrote:

jackdaww wrote:every little helps , but arent hybrids being sold as a major upgrade ?

No, up to now hybrids were mostly sold to company car drivers for the lower tax due to the way they could legally 'cheat' the emissions test.

For the future hybrids are a dead end in mass market cars.

I wouldn't fully bank on that, because the other major advantage of a hybrid is it can be greenwashed and sold to undiscerning people as "environmentally friendly" but still running on petrol, so without the hassle of having to plug it in and wait to charge it. So there will be quite a big market for them for a while yet, until the truth penetrates.

They used to be marketed as 'self-charging electric' cars IIRC, but iIve an idea that was stopped somehow...

AF62 wrote:

jackdaww wrote:every little helps , but arent hybrids being sold as a major upgrade ?

No, up to now hybrids were mostly sold to company car drivers for the lower tax due to the way they could legally 'cheat' the emissions test.

For the future hybrids are a dead end in mass market cars.

jackdaww wrote:same applies to pure EV's , until the national grid is very substantially upgraded to carry mostly renewable power .

Fossil fuel is the minority fuel source for UK electricity production, which is around 40% renewable, 40% fossil fuel, and 20% nuclear.

====================

that sounds good , and it seems there will be more wind farms etc quite soon.

but i wonder how much the national electricity grid has to be upgraded to handle all the oil based power that is currently used on the roads .

is it double ? triple ? DAK ?

Don't forget that some manufacturers only provide buyers with a couple of choices ie......mild hybrid or plug in hybrid. There is no offering of full electric or non hybrid for some models. Therefore some buyers will be buying hybrid by default.

jackdaww wrote:that sounds good , and it seems there will be more wind farms etc quite soon.

but i wonder how much the national electricity grid has to be upgraded to handle all the oil based power that is currently used on the roads .

is it double ? triple ? DAK ?

Seems not. See https://www.nationalgrid.com/stories/jo ... les-busted

Enough capacity exists

With the first of these, the energy element, the most demand for electricity we’ve had in recent years in the UK was for 62GW in 2002. Since then, due to improved energy efficiency such as the installation of solar panels, the nation’s peak demand has fallen by roughly 16 per cent. Even if the impossible happened and we all switched to EVs overnight, we think demand would only increase by around 10 per cent. So we’d still be using less power as a nation than we did in 2002 and this is well within the range of manageable load fluctuation.

Scott.

swill453 wrote:

jackdaww wrote:that sounds good , and it seems there will be more wind farms etc quite soon.

but i wonder how much the national electricity grid has to be upgraded to handle all the oil based power that is currently used on the roads .

is it double ? triple ? DAK ?

Seems not. See https://www.nationalgrid.com/stories/jo ... les-busted

Enough capacity exists

With the first of these, the energy element, the most demand for electricity we’ve had in recent years in the UK was for 62GW in 2002. Since then, due to improved energy efficiency such as the installation of solar panels, the nation’s peak demand has fallen by roughly 16 per cent. Even if the impossible happened and we all switched to EVs overnight, we think demand would only increase by around 10 per cent. So we’d still be using less power as a nation than we did in 2002 and this is well within the range of manageable load fluctuation.

Scott.

=========================

so does this mean that all our road oil based traffic power is just 10% of the power used for homes , factories , business's etc ??

that surprises me .

Cars need much less power to maintain speed than to accelerate, a Reliant Robin can manage 80mph with 40bhp and bravery, eventually.

The advantage of a hybrid is it allows the manufacturer to use a small, light, low power efficient engine which is supplemented by the motors for acceleration, whilst also gaining power from regeneration.

Nissan also do a version which isn't a hybrid at all, but a BEV with an onboard generator that jeeps the battery topped up. This has the advantage that the engine can run in its most efficient state all of the time.

A friend of mine develops engines for Ford. They used to tune engines for performance in all conditions, efficieny was simply a byproduct. Not these days, and he says thermal efficiency is now so high they have to have seperate heating systems, and modern 3 cyl units can be carried by 1 person. Small turbo engines are the current choice for power and economy balance, fewer moving parts means less friction and more economy.

Apparently the biggest hurdle these days to making the vehicles more efficient is peoples' insitance on buying ones with twice the frontal area than 20 years ago.

jackdaww wrote:but i wonder how much the national electricity grid has to be upgraded to handle all the oil based power that is currently used on the roads .

is it double ? triple ? DAK ?

In relation to EV car users you have to consider when most people will be charging their car, and how frequently.

Already most charging happens overnight because that is when the cheap electricity is, and it is cheap because there is a surplus as others don’t want it (offices, shops, most homes, etc.) - although whether it stays cheap with increased EV demand is a good question - but if it doesn’t then that will be a bit of an issue for those with storage heaters who also rely on cheap overnight electricity, but then that will blow a hole in the getting rid of gas boiler government policy.

Charging overnight is convenient for most people; plug the car in and go in the house and next morning the car is ready. Less time actually doing anything than you would spend at a petrol station.

Then how frequently - my EV has a range of 240 miles, which if you think that 8,000 miles a year is on average 155 miles a week, then on average it only needs charging once a week with around 35kWh.

So the amount of charging done at peak times is far lower than the consumption off-peak - some people charging at work (usually because it is offered free) or people needing to top up on long journeys. But most people will choose to charge at 5p/kWh at home and not 50p/kWh at a motorway fast charger.

And then the other factor is that to get the grant to install a home charger it must be a ‘smart’ charger that is installed now. Already I plug my car in at 6pm and tell it I want a full charge by 7am, but to use cheap electricity, and let the charger decide when to do it. Do I care which four or five hours it charges in the 13 hours between 6pm and 7am or whether it is 30 minutes here and an hour there; no, provided the car is charged by 7am. So rather easy for the network to balance the load across all the cars connected to the grid if it needed to.

As it is I can see from the charts provided by the charger that it usually gives the car a half hour charge at the start of the cycle, I assume to check the information it is getting from the car about the battery status is accurate (the car and the charger are linked both through mobile phone networks to talk to each other), and then gives the bulk of the charge later in the charge period.

AF62 wrote:

jackdaww wrote:but i wonder how much the national electricity grid has to be upgraded to handle all the oil based power that is currently used on the roads .

is it double ? triple ? DAK ?

In relation to EV car users you have to consider when most people will be charging their car, and how frequently.

Already most charging happens overnight because that is when the cheap electricity is, and it is cheap because there is a surplus as others don’t want it (offices, shops, most homes, etc.) -

The big overnight electricity users used to be 24hr manufacturing plants, streetlights, and offices/shops (as for some reason they leave their lights on). With the witch to LED, and mant streetlights being off from 00:30 - 05:30, overnight demand is even lower, so spare capacity for charging vehicles is there but ONLY if we use wind or nuclear (or gas/coal, which we should be moving away from). Oddly it is less windy on average at night (someone could explain why, but farmers are usig GPS to giuder machines and shifting towards night spraying as it reduces 'drift' issues due to lower winds) but even so the surplus is there.

so does this mean that all our road oil based traffic power is just 10% of the power used for homes , factories , business's etc ??

that surprises me .

It used to be that transport was about 5% of either emissions or energy use (I can't remember), but yes, a surprisingly small amount.

The most concentrated users were heavy industry, steelworks etc, of which there are now very few.

The issue is still distribution, with domestic supplies capped or bundled into groups of homes with (say) a 150A supply as it is assumed that everybody doesn't draw their 60-100A all at once. Modern homes tend to have a higher rated supply, especially new builds where the underground infrastructure is newer, but some old rural places on overheads might still only have 30-45A supplies per property.

Paul

Paul