The lifespan of Telsa batteries seems to be very many cycles, and of course ultimately an industry that refurbishes them will develop, to extend their life even further. Financially it would be a very bad move for me to go off grid in the connected house as I'd need an expensive battery charger, and a battery, and at the moment my electricity bill is in credit, on average over a year. Thank you long suffering Australian taxpayers, but that's what you voted for.
Is the Diesel dead for autos?
#201
Posted 07 March 2018 - 23:15
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#202
Posted 08 March 2018 - 11:45
And to be honest why would I read car reviews?
Because it's fun! The Citroen DS 5 might not rewrite the rulebook like the original Citroen DS, but don't you think it (or a reinvented Alfa Romeo Giulia) or whatever is very interesting?
#203
Posted 08 March 2018 - 21:39
The lifespan of Telsa batteries seems to be very many cycles, and of course ultimately an industry that refurbishes them will develop, to extend their life even further. Financially it would be a very bad move for me to go off grid in the connected house as I'd need an expensive battery charger, and a battery, and at the moment my electricity bill is in credit, on average over a year. Thank you long suffering Australian taxpayers, but that's what you voted for.
Is that because your "feed in" tariff is heavily subsidised? I know some early adopters in Queensland are still paid 44c/kW.hr which of course is ridiculous.
#204
Posted 09 March 2018 - 03:33
Is that because your "feed in" tariff is heavily subsidised? I know some early adopters in Queensland are still paid 44c/kW.hr which of course is ridiculous.
I'm getting a feed-in tariff of 28c/kWh, which is much the same as the regular power tariff. New solar systems will only get 8c/kWh, however.
#205
Posted 09 March 2018 - 03:49
Ask Tassy about hydro! The HEC has nearly run Tasmania over the decades but no water= no electricity.
I suspect the Snowy Scheme is probably safer but not by much.
The problem is with all 'renewables' is that they are not base load. And never will be.
I beleive similar has happened in the US as well with the Colorada River?
As far as I recall, it has only happened, to any major degree, when we were joined to the mainland with the Basslink cable.
In trying to maximise the dividends to the government, the Hydro sold power to the mainland at a premium, running down the reserves. And then the Basslink cable broke.
There was a coal fired power station in the north of the state, near some heavy industrial power users (including Comalco), which was changed over to a gas turbine plant using both open and combined cycle turbines. It has been used so little in recent years that the AEMO had to order it to fire up last year (along with some others on the mainland).
The problem with the Snowy II scheme is that it is to be a pumped storage facility, which has huge capacity but is too centralised. Smaller pumped hydro systems in various locations would be better, and probably cheaper. The idea of using the sea as the lower reservoir is good and would avoid the problem of finding water to store. There are a few sites being investigated now.
Regarding South Australia's Diesel generators, are they running on Diesel fuel or natural gas?
#206
Posted 09 March 2018 - 14:13
The lifespan of Telsa batteries seems to be very many cycles, and of course ultimately an industry that refurbishes them will develop, to extend their life even further.
Lead acid battery recycling is/was a simple process.
* Can the cell be rejuvenated? This is about applying short time recharges to the cell and testing whether the cell can hold a charge at desired voltage after a few minutes. Can you repeat it many times? Have you tried to rejuvenate the cell before the plates were damaged?
* Bust the case open and ideally take care of the waste acid. Send the lead to the scrap yard.
The batteries in a Tesla comprise many cells. I presume that they are not designed to be disassembled for replacement of individual cells.
In the long term, there might be standard-ish batteries with standard-ish cells. Fixable stuff. In the mean time, electric vehicle manufacturers are making tech up.
#207
Posted 09 March 2018 - 18:03
Is that because your "feed in" tariff is heavily subsidised? I know some early adopters in Queensland are still paid 44c/kW.hr which of course is ridiculous.
Yes, my feed in tariff is subsidised by me and other tax payers in the People's Republic of Victoria. It is currently at 17c /kWh for the first 12 kWh per day, and 12c/kWh thereafter. This seems to be averaged over the billing period. That's a new rate that was set at the start of the year, roughly. I average something like 20 kWh per day over the year. In the depths of winter I probably will not hit that 12 kWh limit, particularly now I have reverse cycle heating. I could get a heat pump hot water system as well (currently on solar/ instant gas) at which point if I got a new cooker we could kill the gas connection.
Regarding South Australia's Diesel generators, are they running on Diesel fuel or natural gas?
SA's new generators (they are gas turbines) run on diesel at the moment, but in a couple of years time the dozy idiots will have managed to organise a gas supply. The supreme idiot has just announced a 75% renewable energy target.
@V8 I don't read car reviews because I have met many motoring journalists, and I have read what they write about cars that I know very well. Their job is to sell fish and chip wrappers. I do read Clarkson, because he makes me laugh.
@Charlieman - if somebody can fix a $1000 iPhone, somebody will figure out how to fix a $5000 Powerwall. I'd guess the on board diagnostics even tell you which cells are bad- the cells are dynamically linked so that bad cells are not used.
Edited by Greg Locock, 09 March 2018 - 18:10.
#208
Posted 09 March 2018 - 18:42
@Charlieman - if somebody can fix a $1000 iPhone, somebody will figure out how to fix a $5000 Powerwall. I'd guess the on board diagnostics even tell you which cells are bad- the cells are dynamically linked so that bad cells are not used.
If the bad cells next to you, either side, are bad, how do you explain that you are a bad battery cell?
#209
Posted 14 March 2018 - 17:56
On a related note, I see a press comment to the effect that the supply of household solar generation is becoming so great that the price will drop. The industry needs to be very careful here, the falling price of batteries is nearing breakeven point, and when that happens, large numbers of people will desert the grid, seriously disturbing the pricing model that sustains the retail, distribution and production of electricity (the latter two will be most affected). Already standing charges are becoming a much more significant part of the electricity bill, and as these and unit prices are increasingly used to offset falling demand, the maths lean more towards the off-grid solution. When the crossover occurs the retailers will see the number of consumers starting to fall, and the distributors and producers will see their demand falling. This then sets up a classic death spiral of increased price leading to reduced demand leading to increased price and so on. I find it difficult to see how to prevent this, the only questions are the timeframe for the initial phase, and the rate thereafter.
Electricity providers are already facing the problem of falling revenues due simply to improving efficiencies. All of the LED light bulbs and TVs replacing incandescents and CRTs (and all of the other efficiency gains) are actually reducing electricity demand in spite of increasing population and GDP. The utilities are starting to worry about being able to pay off the debt on their big new plants. And this is before people start dropping off the grid in significant numbers.
http://www.businessi...-impact-2017-12
#210
Posted 14 March 2018 - 23:13
Politician . . "Yeah but . . . . . . . . lets build some new coal fired power stations."
Electricity provider . . . "Only if you pay for them."
Edited by gruntguru, 14 March 2018 - 23:19.
#211
Posted 15 March 2018 - 01:11
I don't know how the Tesla battery pack's OBD works, I do know that it has a dedicated reserved group of cells that can be dynamically switched in to replace duds. This is essential in a large LiOn battery as bad cells can burst into flames or explode if you ignore them. We lost a solar car that way.
#212
Posted 15 March 2018 - 13:41
In wealthier nations, we see knee jerk responses to revelations of diesel emissions cheating. Customers have stopped buying diesel cars as much and legislators are looking at diesel car usage in cities. What would have happened if it had been demonstrated that manufacturers were gaming the emissions figures for petrol ICE cars?
When considering combustion factors for ICE design -- whatever the fuel -- you have the following:
* Fuel use efficiency -- with enough power and torque to operate safely.
* CO2 emissions. I'll ignore CO on the basis that it is so easily converted to CO2 in the natural environment.
* NOx emissions.
* Particulate emissions -- soot, unburnt fuel.
* Sulphur compound emissions -- probably not a problem with cars, certainly one for marine and farm use diesel in developing nations. I'll ignore this factor because it can be best addressed by cleaning up fuel.
In order to achieve the first on the list -- fuel use efficiency -- designers have to be creative whilst juggling the next three factors -- CO2, NOx and particulate emissions. It turned out that some people at car manufacturers found a few engineers prepared to create cheat systems for diesel engines. And so public opinion -- a significant part -- determined that diesel is "bad". Nobody considered whether similar cheats have been applied to conventional or hybrid cars with petrol ICEs.
NOx emission limits matter a lot. Hybrid engines in F1 cars achieve almost incredible thermodynamic efficiency (and consequentially low CO2 emissions) at a cost of huge NOx parts per million. Pumping NOx from the exhaust pipe at a race track or open country road isn't much of a problem. Like CO emissions, they are absorbed locally in open spaces. Mostly.
NOx is a city problem but so is urban planning. Streets surrounded by tall buildings -- canyon avenues -- create regions where pollution is never blown away or absorbed. Underground industrial plant for telecoms, power distribution or air conditioning increases temperature at ground level. That should be good for NOx recycling or absorption into the natural environment -- but there is insufficient wind or nature for it to happen.
I think that diesel cars have a place outside big cities. I also think that environmental campaigners need to think a bit bigger about how pollution happens.
I don't know which particular elements of badly run diesel engines I am breathing in, when I cycle across the city in traffic, but you can quickly tell when you are behind such a vehicle. Sometimes I literally have to take in a big breath of air and hold it until I get past certain cars, buses or lorries, because breathing in their fumes actually makes you want to retch. We need to get all diesel engines off the city roads, they can be really bad. It's when they are not running properly, but of course the driver doesn't notice that themselves.
I would say that half an hour's cycling in central Bristol is roughly equivalent to smoking two cigarettes. Something like that.
#213
Posted 15 March 2018 - 16:59
I would say that half an hour's cycling in central Bristol is roughly equivalent to smoking two cigarettes. Something like that.
We need to ban cycling as soon as possible. Not only are you breathing in all this pollution and becoming a burden on the NHS, but you are causing extra congestion, adding to the pollution from the delayed traffic. And cycling is really dangerous too, making cyclists a further burden on our hard pressed NHS when they get squished.
For your own good, we should ban it now - especially as so few BME and LGBT people cycle, showing that it is seriously non-diverse. Remember, the state knows best what is good for you.
#214
Posted 15 March 2018 - 17:16
The speed limit doesn't apply to cycles, and as Bristol has a limit of 20 MPH in most places, it's actually the cars that are slowing me down most of the time.
#215
Posted 15 March 2018 - 23:15
@V8 I don't read car reviews because I have met many motoring journalists, and I have read what they write about cars that I know very well.
I have noticed that Australian motoring journalism is usually sensationalised hyperbole, and I can't stand it.
I find that the relaxed demeanour of the British or Canadian provide the most well-rounded commentary. There is also the highly factual testing done by American anoraks such as Savagegeese, Saabkyle04 and Alex on Autos (Youtube video bloggers) which is usually of a high degree of quality and impartiality IMO.
Edited by V8 Fireworks, 15 March 2018 - 23:15.
#216
Posted 15 March 2018 - 23:17
We need to ban cycling as soon as possible. Not only are you breathing in all this pollution and becoming a burden on the NHS, but you are causing extra congestion, adding to the pollution from the delayed traffic. And cycling is really dangerous too, making cyclists a further burden on our hard pressed NHS when they get squished.
Nice satire.
London sure does have a HUGE air quality problem. It is almost certainly due to the diesel passenger car fleet, and would almost certainly be mostly alleviated by replacing the diesel fleet with a petrol-electric hybrid fleet as the policy of Los Angeles has shown so well by comparison to EU policy. BUT it is important the petrol cars are NOT direct injection, as those produce particulates as bad or worse than diesel cars. TLDR: Everyone should drive a Prius with a nice conventional port injection petrol engine.
Road and track magazine have a (seemingly unbiased) opinion piece here: https://www.roadandt...iesel-gdi-bans/
Edited by V8 Fireworks, 16 March 2018 - 02:52.
#217
Posted 16 March 2018 - 00:31
I remember (UK) Car magazine doing a glossy 4 or 6 page spread on the upcoming Elan. My friend read it with great interest, boy did his face fall when i told him the journo hadn't driven the car at all. When that article was published there were a few very ratty looking protos around and nothing fit for public consumption.
#218
Posted 16 March 2018 - 03:56
I remember (UK) Car magazine doing a glossy 4 or 6 page spread on the upcoming Elan. My friend read it with great interest, boy did his face fall when i told him the journo hadn't driven the car at all.
Was that mentioned in the article? I read CAR occasionally, and as far as I recall they always mention whether they drove it or not (or were driven), and whether the car was representative of a production sample.
#219
Posted 16 March 2018 - 07:06
Not that I remember. it certainly wasn't obvious that he hadn't driven it.
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#220
Posted 16 March 2018 - 09:25
The lifespan of Telsa batteries seems to be very many cycles, and of course ultimately an industry that refurbishes them will develop, to extend their life even further. Financially it would be a very bad move for me to go off grid in the connected house as I'd need an expensive battery charger, and a battery, and at the moment my electricity bill is in credit, on average over a year. Thank you long suffering Australian taxpayers, but that's what you voted for.
I did not vote, or have any chance to vote about solar rooftop tarriffs. Like a large number of people I am subsidising this very innefficient disaster.
Solar in large scale operation may be viable but the stupid subsidies are economically beyond belief.
Stupid governments with stupid so called Green ideas have quadrupled the cost of electricity in SA and not much better else where. And as we all know made it electricity far less reliable.
Even with 50 million dollar batteries, and the same in diesel,,,, yep [green!!] diesel generators SAs power is still knife edge. IF we have not lost so much manufacturing in this state blackouts would very regular. So they build trams to nowhere duplicating bus routes,,Drrrrrrrr
And today we find that the govt has approved a gas fired electricity generator. Much needed but they could of had it a decade ago by dealing with the Pt Augusta owners who wanted certainty then to spend up large to upgrade.
#221
Posted 16 March 2018 - 09:34
Electricity providers are already facing the problem of falling revenues due simply to improving efficiencies. All of the LED light bulbs and TVs replacing incandescents and CRTs (and all of the other efficiency gains) are actually reducing electricity demand in spite of increasing population and GDP. The utilities are starting to worry about being able to pay off the debt on their big new plants. And this is before people start dropping off the grid in significant numbers.
Having in the past few weeks replaced fluro light globes that did NOT last the advertised life, and a LED one too that failed [and was lousy light at best!]
Yet my power bill has gone up heaps, and I am a consistent user and fairly frugal as well. And seldom run heaters in winter or AC in summer. Rugs when cold and keep the blinds down and have decent eaves unlike so called dumb modern homes so may run AC a few times a month.
Talking to someone who owns a Tesla, he feels shonked as his meter runs really fast when the car is on charge. And the thing does not have near the advertised range either. He does live in a damp cold valley however so his solar panels are less than ideal as well.
#222
Posted 16 March 2018 - 09:36
As far as I recall, it has only happened, to any major degree, when we were joined to the mainland with the Basslink cable.
In trying to maximise the dividends to the government, the Hydro sold power to the mainland at a premium, running down the reserves. And then the Basslink cable broke.
There was a coal fired power station in the north of the state, near some heavy industrial power users (including Comalco), which was changed over to a gas turbine plant using both open and combined cycle turbines. It has been used so little in recent years that the AEMO had to order it to fire up last year (along with some others on the mainland).
The problem with the Snowy II scheme is that it is to be a pumped storage facility, which has huge capacity but is too centralised. Smaller pumped hydro systems in various locations would be better, and probably cheaper. The idea of using the sea as the lower reservoir is good and would avoid the problem of finding water to store. There are a few sites being investigated now.
Regarding South Australia's Diesel generators, are they running on Diesel fuel or natural gas?
Jays Green diesel. At 100s of gallons an hour! And reputedly running very regularly over this summer. So much for Green Power!
As for Taswegia,, Bell Bay has been there for decades and was seldom used. The Basslink cable broke,, but where was plan B. The Hydro would not want any competition so yes they were on diesels as well.
Edited by Lee Nicolle, 16 March 2018 - 09:40.
#223
Posted 16 March 2018 - 18:22
London sure does have a HUGE air quality problem. It is almost certainly due to the diesel passenger car fleet
Nope. We've been through this before. London does not have a huge air quality problem. Agenda-driven activists have imposed targets that an Alpine meadow in springtime would struggle to meet. The air quality in London is now better than it has been since about AD1500.
What pollution there is (and I recognise that there is some and that we should be trying hard to reduce it) is due to buses, not cars. In the aftermath of the terrorist bus and Tube bombings in 2007, London's Oxford Street - the worst air quality in London - suddenly became pristine. Why? Because all the buses were suspended and no other traffic is allowed along that street.
But that fact is conveniently overlooked in the continuing campaign aginst the car which is of course the root of all evil.
#224
Posted 16 March 2018 - 23:06
As for Taswegia,, Bell Bay has been there for decades and was seldom used. The Basslink cable broke,, but where was plan B. The Hydro would not want any competition so yes they were on diesels as well.
The whole point of Basslink was to have competition in Tasmania.
And some industrial users did change to buying power from the mainland, while the hydro sold their power over there - at a premium, as "green" power.
Diesels were brought to Tassie just in case, but I don't believe any were actually used. Bell Bay was.
Edited by Wuzak, 16 March 2018 - 23:28.
#225
Posted 16 March 2018 - 23:30
Jays Green diesel. At 100s of gallons an hour! And reputedly running very regularly over this summer. So much for Green Power!
They may well have been running because there were several failures of coal fired generators in Victoria and New South Wales over the summer.
#226
Posted 17 March 2018 - 01:14
Well I'm sure the transparent and accountable government will release those figures over time. After the election.
#227
Posted 17 March 2018 - 03:05
Nope. We've been through this before. London does not have a huge air quality problem. Agenda-driven activists have imposed targets that an Alpine meadow in springtime would struggle to meet. The air quality in London is now better than it has been since about AD1500.
But that fact is conveniently overlooked in the continuing campaign aginst the car which is of course the root of all evil.
Everything you said is wrong IMO.
London does, however, still earn its nickname as "The Big Smoke" - because although PM2.5 is responsible for the greatest number of deaths worldwide, nitrogen dioxide kills more people in London, responsible for 5,879 deaths.
https://www.telegrap...her-cities.html
Edited by V8 Fireworks, 17 March 2018 - 03:06.
#228
Posted 17 March 2018 - 03:11
Yet my power bill has gone up heaps, and I am a consistent user and fairly frugal as well.
Install a taxpayer subsidised home solar system! The STC credits pay for half or even more than half of the system cost. I would suggest Sunterra, they are very reasonably priced. The panels last more or less indefinitely, just budget for a new Chinese inverter ($700 or so) every 5 five years (which is still cheaper than the German inverters which are $1500AUD+).
Even with the meagre 6c minimum feed-in tariff your power bill should go down drastically (from say $1000p/a to $200 p/a -- the more of your own solar power you use, the bigger the saving since self-use is saving 32 c/kWh), generating (pardon the pun) an incredible 20-40% return on "investment" and a very quick 3 or 4 payback period.
#229
Posted 17 March 2018 - 06:00
Having in the past few weeks replaced fluro light globes that did NOT last the advertised life, and a LED one too that failed [and was lousy light at best!]
Yet my power bill has gone up heaps, and I am a consistent user and fairly frugal as well. And seldom run heaters in winter or AC in summer. Rugs when cold and keep the blinds down and have decent eaves unlike so called dumb modern homes so may run AC a few times a month.
Talking to someone who owns a Tesla, he feels shonked as his meter runs really fast when the car is on charge. And the thing does not have near the advertised range either. He does live in a damp cold valley however so his solar panels are less than ideal as well.
I have used an LED light for 3 or 4 years now. It is, IIRC, an 11W globe and sits in a 40 or 60W fitting. The LED is way brighter than the old incandescent or fluoro lights I have had in the past. The incandescent globes failed frequently, the fluoros occasionally, but the LED has yet to fail.
One factor that has also increased power prices is the network costs. These can take up to 50% of your power bill, in some places maybe more. And it seems that the less power customers use, the higher the network fees become.
It isn't unusual that your Tesla owning mate doesn't get the advertised range, as that would be calculated under ideal conditions. I'm sure many people struggle to match the fuel consumption figures of non-EVs in the real world too.
Of course charging the Tesla at home is going to up the power bill. If he is charging from near empty, the battery will require 5 times, or more, the energy required to run a house for a day.
It would be interesting to see the comparison between his weekly power bill, for the car, against the fuel bill for his previous vehicle, assuming his vehicle usage is similar to before, or the same.
#230
Posted 17 March 2018 - 11:02
I would say that Diesel has its place, but due to the obvious complexities of trying to manage who drives what and where they do that(not in cities but ok everywhere else++).. diesel is dead for personal vehicles. It will be limited for trucks and haulers in the future.
Easiest is to tax them for private use and/or below a certain size.
In this modern day and age it should not be too hard to tax only diesel cars in automatic tolls too mind you. So taxing companies with diesel haulers in the cities is doable.
This might be a niche marked for Tesla trucks(hauling into the cities from drop offs outside of the cities, avoiding tolls entirely)
Edited by MatsNorway, 17 March 2018 - 11:03.
#231
Posted 17 March 2018 - 13:38
In this modern day and age it should not be too hard to tax only diesel cars in automatic tolls too mind you. So taxing companies with diesel haulers in the cities is doable.
You have to consider the accuracy of ANPR -- number plate recognition -- or other ways of identifying energy type. ANPR in the UK operates at about 97% accuracy. ANPR gets it wrong thousands of times a day.
#232
Posted 17 March 2018 - 14:04
I have used an LED light for 3 or 4 years now. It is, IIRC, an 11W globe and sits in a 40 or 60W fitting. The LED is way brighter than the old incandescent or fluoro lights I have had in the past. The incandescent globes failed frequently, the fluoros occasionally, but the LED has yet to fail.
Yep, that's how anecdotal evidence works.
Science suggests that if you keep a fluorescent bulb or tube alight constantly, it will still be alight when you pass away. You don't want to turn it off too many times but it will survive a few power cuts.
Flipping the switch on any light bulb shortens its life span. You have to determine the energy and life cost of turning it on and off; and cost the employment of somebody up a ladder -- the cost of bulb or tube replacement, plus sending an invoice internally or externally.
For a business it makes sense to buy long life, low power bulbs and tubes. For a householder, buy expensive low power bulbs for rooms where you live. Use displaced bulbs to light your loft or the spare bedroom.
#233
Posted 17 March 2018 - 19:58
Did you actually bothet to READ the article that you quoted?
It says that London is only the 2,516th worst polluted city in the world out of 3,226 cities. So I am right there. And given that London has more than 10 million people and the comparison is with all cities with more than 100,000 people makes its performance even more impressive.
The article quotes the Clean Air in London campaign and the Green Party - agenda-driven activists by any standards. So I am right there too.
There is then a dubious claim of 5,879 deaths due to NOx. Who says so? We aren't told of course. I would bet that there wasn't a single death certificate issued giving NOx as the cause of death. It is just some sort of guesstimated extrapolation for sensational reasons, doubtless emanating from the above mentioned agenda-driven activists. Those people suffered from conditions that MIGHT have been exacerbated by pollution but no-one knows if they wouldn't have died anyway.
So basically, everything that I said was right and everything that you have said is wrong.
#234
Posted 18 March 2018 - 02:59
Did you actually bothet to READ the article that you quoted?
It says that London is only the 2,516th worst polluted city in the world out of 3,226 cities.
Hoorah for London!
How many 3rd world cities in the top 710? How many first world cities in the worst 2515?
#235
Posted 18 March 2018 - 03:06
Yet my power bill has gone up heaps, and I am a consistent user and fairly frugal as well. And seldom run heaters in winter or AC in summer. Rugs when cold and keep the blinds down and have decent eaves unlike so called dumb modern homes so may run AC a few times a month.
Install a taxpayer subsidised home solar system! The STC credits pay for half or even more than half of the system cost. I would suggest Sunterra, they are very reasonably priced. The panels last more or less indefinitely, just budget for a new Chinese inverter ($700 or so) every 5 five years (which is still cheaper than the German inverters which are $1500AUD+).
Are you serious??? That would eliminate one of his favourite topics for a mindless rant!!!
#236
Posted 18 March 2018 - 20:51
Hoorah for London!
How many 3rd world cities in the top 710? How many first world cities in the worst 2515?
What? Am I supposed to be the only one who actually reads these reports? Look it up yourself, but here's a spoiler. Worse than London, with its 'HUGE air quality problem' are, amongst many others, New York, Chicago, Long Beach, Milan, Rome, Florence, Berlin, Dusseldorf, Dresden, Toronto etc.
And since this seems to be a bit of good old Aussie Pom-bashing, you can add your very own Federal Capital, Canberra.
#237
Posted 18 March 2018 - 22:59
Hello all.
"Is the Diesel dead for autos?"
An answer could be: "No more than the conventional spark ignition engines."
If what Mazda claims (with their SkyActiv-X HCCI technology) is true, the conventional spark ignition engines (those with the progressive combustion) have similar issues with the conventional Diesels.
Both, the spark ignition engines and the Diesel compression ignition engines, will be replaced by "compression ignition" HCCI engines.
#238
Posted 19 March 2018 - 02:31
I'm a bit astonished by the claim that the modern car exhausts (of whatever flavor) are the dominant cause of breathable nasties. Most times I am choking to death it is some old heap belching burnt oil past its oval shaped valve guides and paper thin rings, or some 20 year old diesel black smoking cos its owner tuned it for maw par.
#239
Posted 19 March 2018 - 05:20
Manolis.
Comparing PatBam and Mazda's SPCCI it seems that both seek to generate HCCI in a large part of the chamber by starting a small fire in the centre to raise the temperature and pressure of the remaining charge above its auto-ignition state. Some advantages of each system are:
PatBam
- No spark plugs
- Temp and pressure and turbulence increase when port opens
Mazda
- Timing can be varied
- Non-HCCI mode available
- Spark available for cold start etc
Watching the Mazda video, I don't share your confidence that PatBam can operate in HCCI mode over a wide range of operating points without fine control over AFR and EGR, and with a main-chamber CR significantly less than 16:1
Edited by gruntguru, 19 March 2018 - 05:34.
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#240
Posted 19 March 2018 - 14:27
Hello Gruntguru.
You write:
“Watching the Mazda video, I don't share your confidence that PatBam can operate in HCCI mode over a wide range of operating points without fine control over AFR and EGR, and with a main-chamber CR significantly less than 16:1”
In the auxiliary chamber the compression ratio is high enough to cause, at all conditions, the auto-ignition of the air-fuel mixture therein.
In the main chamber the compression ratio has to bring the air-fuel therein near, yet below, the threshold for auto-ignition, and depends on the fuel used.
With cheap low octane fuel (like the gasoline used a century ago in car engines having 5:1, or so, compression ratios, or like the n-heptane), the compression ratio for auto-ignition is low (~ 8:1).
The 8:1 is too low and spoils the BTE.
Similarly the 16:1 is too high and puts several limitations to the engine design (heavier parts, lower rev limit, vibrations etc), offering only marginal increase(?) of the BTE.
Around 12:1 to 13:1 compression ratios in the main chamber seem good. Using low octane gasoline (87RON or, preferably, lower if available) the running cost reduces.
Here it is shown the piston 10 degrees BTDC:
and here the piston at the TDC:
With, more or less, all the air-fuel mixture of the main chamber concentrated into the bowl, the transfer ports open and the burnt (or still burning) gas (yellow) from the auxiliary combustion chamber bursts / explodes / rushes / plunges / dives into the bowl.
With the air-fuel mixture into the bowl being below, yet near, the threshold for auto-ignition,
with a maximum distance of 20mm from the transfer ports to the ends of the bowl,
and with, say, 500m/sec speed of the burnt gas exiting from the transfer ports (and, say, 500/5=100m/sec mean speed into the compact bowl),
the time required for the burnt gas to arrive to the ends of the bowl is:
0.02m / (100m/sec) = 0.0002 sec = 0.2msec.
This time interval corresponds to 7 crankshaft degrees at 6,000rpm.
During the initial part of the above mass transfer of hot / burnt gas to the ends of the bowl, another phenomenon takes place.
The compressed, but not yet burnt, air-fuel mixture into the main chamber undergoes a rapid / abrupt / sudden increase of its pressure.
The pressure wave from the opened transfer ports arrives to the ends of the bowl with sound velocity (the sound velocity at the specific temperature).
Before the opening of the “transfer ports”, the molecules / atoms of the air-fuel mixture in the main chamber are at equilibrium, yet at an “unstable equilibrium” because they are near the threshold for auto-ignition (similarly, the standing playing cards in the video are at an “unstable equilibrium”: a small displacement of the basis whereon they are standing, and they all fall).
The abrupt increase of the pressure after the opening of the “transfer ports” causes the local increase of the temperature and the spontaneous ignition of all the air-fuel mixture in the bowl (similarly, the slight displacement of the basis whereon the playing cards stands, video, causes the simultaneous fall of all the playing cards).
It seems that the two dominant factors (pressure wave and mass transfer) are supporting each other, are complementary.
What is left unburned by the pressure impact, will be burnt by the mass transfer.
At the end, either an HCCI instantaneous combustion or a very fast combustion (completed in a few crankshaft degrees) have similar advantages over the BTE and the emissions.
The “fast combustion” is what Mahle is pursuing with their TJI.
According the following SAE / Mahle paper:
the average speed of the jet of the Mahle TJI is near 60m/sec:
This makes pessimistic my previous assumption for 100m/sec average jet speed (or "mass transfer" speed) when the transfer port opens in the compact bowl (~20mm maximum distance) of the above post PatBam HCCI.
On one hand the distance the jet of the burnt / burning gas covers in the PatBam bowl is short (say 20mm), on the other hand the pressure difference is way higher.
It is also a “converging” flow: at the first 10mm of their travel, the burnt gas molecules / radicals from the auxiliary chamber have reach the big majority of the mass of the unburned air-fuel mixture in the “main chamber” / bowl of the PatBam.
Worth to note: in the Mahle TJI the small chamber is permanently “open” to the main chamber (through the nozzle orifices):
while in the PatBam HCCI the auxiliary chamber opens after the combustion, which means substantially higher pressure differences.
It is the primitive / archaic geometry of the PatBam HCCI against the “fine” tuning, the delicate control, the sensors, the multiple high-pressure injections, the programming of the ECU of the Mazda SkyActiv-X HCCI (SP-CCI).
Thanks
Manolis Pattakos
#241
Posted 20 March 2018 - 14:52
Hello Gruntguru.
High speed operation of Mazda’s SkyActiv-X and of the PatBam HCCI:
Mazda uses a high pressure injector to directly inject (let call it auxiliary injection) a small quantity of fuel onto the spark plug to form a stoichiometric mixture locally surrounding the spark plug (while the rest cylinder contains lean air-fuel mixture), and only later it can ignite it with the spark plug, so that an expanding “fire ball” can be created in order to compress the rest mixture beyond the threshold for auto-ignition.
The advance (crankshaft degrees before the TDC) of the auxiliary fuel injection and the advance of the spark plug are variable by the ECU so that the HCCI (the instantaneous) combustion of the rest air-fuel mixture into the cylinder to happen just after the TDC (but always the spark is second and the injection first).
At lower revs things are easy.
A few degrees before the TDC the auxiliary injector injects on the spark plug, the turbulence and swirl are weak, the spark can occur soon after to create the “fire ball” which increases the actual compression of the rest (lean) air fuel mixture in the cylinder in order to cause its auto-ignition / instantaneous combustion (HCCI).
At medium revs things get tough: a bigger advance of the injection and of the spark, together with the increased turbulence and swirl make harder the creation of a stable fire ball.
At high revs thing get from difficult to impossible.
The spark requires a big advance, say 45 crank degrees BTDC (in the Ducati Panigale they were using even 60 degrees spark advance for stoichiometric mixture).
The auxiliary injection requires an even longer advance: 60? 70? 80? degrees in order to succeed to have the plug surrounded by fuel before the spark.
The increased turbulence and swirl in the cylinder (due to the high revs) cannot but wash the external periphery of the initially tiny fire ball...
The fire ball fades / evaporates / disappears before causing the increase of the temperature of the lean mixture above the threshold for auto-ignition.
And the engine misfires.
The only solution is the engine to switch back to stoichiometric mixture and to the conventional spark plug progressive combustion.
If the Mazda SkyActiv-X prototype cars are accused for something by the journalists who drive tested them, it is the noisy, the rattling transmission from the one mode (HCCI) of operation to the other mode (conventional spark ignition / stoichiometric mixture).
Instead, in a spark-plug-less PatBam:
At higher revs the sealing of the auxiliary combustion chamber is better (the time for leakage reduces).
The lean mixture inside the auxiliary combustion chamber cannot help auto-igniting.
The moment the “transfer port” opens, the burnt or still burning gas burst into the bowl wherein it is compressed all the rest air-fuel mixture.
The shock for the already compressed and slightly below the threshold lean air-fuel mixture causes its auto-ignition.
Even if for some reason the shock fails to cause the HCCI combustion, the mass transfer of burnt / burning gas into the unburned mixture causes its fast combustion (say, in a way faster mode than the TJI of Mahle causes the fast combustion in the F1 engines).
Either way, the combustion completes a few degrees (say, less than 15) after the TDC.
And there is no need for transition between different modes of operation (as in the Mazda SkyActiv-X).
Theoretically, it will ignite because it has not another choice.
And the higher the revs, the easier the ignition.
Thanks
Manolis Pattakos
#242
Posted 06 September 2018 - 02:56
I agree too, as far as that post goes.
The auto world is facing great change, and Musk is at the leading edge of that change. However that carries big risks, and it remains to be seen if, even though Musk is a great innovator, he can also be successful in this venture. For the moment though, it is clearly a case of 'so far, so good'.
https://www.drive.co...&trackLink=SMH1
That quote of mine was just over two years ago. Musk is increasingly prone to brain farts, Tesla is still struggling to get its game together, and the big boys are coming to play in his sandpit. This is not going to end well for Elon. If he is lucky, Tesla will be bought up by someone like Merc or VW.
If he is not, well he has other toys to play with.
#243
Posted 06 September 2018 - 14:51
The fact that a small start-up with non-existent resources compared to the large existing manufacturers got a significant technical leg up on them, held on to it for years, and still have it even after billions being spent chasing after Tesla for fifteen years strongly suggests to me that either Musk and Tesla are geniuses, or that the existing engineering departments of the big makers are really fundamentally incredibly and painfully limited at what they are capable of accomplishing. Most likely a slice of both.
#244
Posted 06 September 2018 - 20:44
The fact that a small start-up with non-existent resources compared to the large existing manufacturers got a significant technical leg up on them, held on to it for years, and still have it even after billions being spent chasing after Tesla for fifteen years strongly suggests to me that either Musk and Tesla are geniuses, or that the existing engineering departments of the big makers are really fundamentally incredibly and painfully limited at what they are capable of accomplishing. Most likely a slice of both.
You missed the third option. Electric cars were so niche until recently and the profit margins on Diesels etc so great that it wasn't worth bothering. Now that electric cars are gaining popularity and acceptance (thanks to a large degree to Tesla), the big boys are moving in to do the job properly. They'll manage it too because they can do several things Tesla currently can't, mass produce vast quantities of cars with a low probability of defects, distribute, sell and service them globally with a large cash stockpile. They also lack something Tesla has a monopoly of, a boss that can't be bothered to engage with investors and accuses people he's never met several times of being a paedophile.
#245
Posted 06 September 2018 - 20:47
Two ways of looking at that. (a) Getting funding for blue sky disruptive projects is rather hard. (b) the money is made by bringing the profitable version to market, and that is not usually going to be the first on the market. The second is actually the stronger reason. Either way it is mostly about money.
Quite simply Tesla has spent 4 billion dollars (ie accumulated losses to date) and makes a loss even now. His shareholders fund that, great. Non acolytes wouldn't. 4 billion dollars is a company sized bet for Ford. That's about 6 platforms that would have to be abandoned, and all that to build 1/4 million cars a year after 9 years.
I'm not saying Tesla will fail financially, although that is quite likely. They did one good thing, demonstrating that current tech is good enough for practical EVs for people who can afford them.
#246
Posted 07 September 2018 - 17:03
Tesla got a huge boost from the discovery that the whole ICE motor industry was cheating on emissions. WIthout that, we would still all be happily buying diesels and laughing at those silly people wasting money on expensive EVs.
But the downside for Tesla was that now the whole motor industry is developing EVs like gangbusters and they have the resources and R & D capacity to squish a minnow like Tesla. All not helped by Musk's increasingly odd behaviour.
#247
Posted 08 September 2018 - 06:46
I suspected VW was cheating on their diesels in 2009 when they came back to North America..... miraculously..... without the need for AdBlue or similar. Avoided buying one for that reason....plus I hate how they look.
#248
Posted 10 September 2018 - 17:33
Tesla might fail. But right now there is yet to be a better electric car out there in terms of spesifications such as range and safety level. They are also seemingly in the lead when it comes to driving assist features in traffic and "simpler" pleasures such as summoning.
Tesla might have sold their cars too cheap. There where for a period at least people buying more than one and then flipping them.
Edited by MatsNorway, 10 September 2018 - 17:36.
#249
Posted 04 October 2018 - 18:39
Sadly, I admit that Diesel for passenger cars is on its death knell in North America, and that blight is already spreading in Europe, the most resilient Diesel stronghold.
BUT #1:
History shows that all it takes is for crude oil to reach, say, USD$120/bbl - like it did in Dec 1979 in current dollars https://inflationdat...rices_Chart.asp - before we go scrambling again. Whether it will happen in any near timeframe is up for debate.
BUT #2:
Politicians will come and go, and I believe a point of realisation will come that the current hysteria over Diesel NOx (because NOx of contemporary pass. car Diesel, even over WLTP, is far less per kWh than industrial, fossil power generation, rail, and marine emissions) and soot emissions (with DPFs) were overblown and there will be renewed scrutiny on gasoline engine emissions (GDI particulates and cold-start HC, VOCs &CO ).
Unfortunately, it's probably too late for Diesel pass. cars, which is why I plan to keep my 20-year-old Audi A4 TDI Avant quattro that I personally imported to Canada from Germany for as long as possible, and I will also be looking to add another used Diesel car to my long-term fleet and look at replacing my wife's Dodge Caravan with over 426k km with a PH(EV) - since most of her driving is short, in-city trips - like a Mitsubishi Outlander, Chrysler Pacifica or Ford Transit.
Up until recently, my entire engineering career and education was in the automotive, specifically ICE industry. Now my focus is on power generation from renewable or waste sources, exploiting pyrolysis and gasification to produce fuels for cogeneration/CHP.
If anyone is interested, pretty much the entirety of my research bibliography, many with full-texts:
Edited by TDIMeister, 04 October 2018 - 18:41.
#250
Posted 04 October 2018 - 21:39
Thankyou David I read with interest your work on
Vortex-Stratified Combustion Process