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Author Topic: Should I turn off my engine?  (Read 3930 times)

Offline Don_1

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Should I turn off my engine?
« on: 11/01/2012 13:12:11 »
On a similar vein to Chris's thread here, I have an email from TFL (Transport For London, or as I think of them Tosspots F***up London):-


Dear Mr Don_1,

I am writing to remind you that leaving your engine idling unnecessarily can contribute significantly to local pollution levels.
 
If you know you are going to be stationary for more than a minute, turning off your engine will reduce harmful emissions. This small change can have a big impact so please help by turning off your vehicle’s engine whilst parked or waiting at the roadside. By doing this we can all breathe cleaner air.
 

We have updated our website with information relating to engine idling and improving air quality. For more information, please visit tfl.gov.uk/switchoffengine

TFL are also running a radio information campaign urging delivery drivers to turn off their engine when making a delivery.

What a bunch of plonkas.

If I were making a delivery in London, I would certainly NOT leave my engine running. Apart from the fact that it’s illegal to leave a vehicle unattended with its engine running, it would be inviting every thief for miles around to make off with my van and its contents.

As for leaving my engine running when I am parked, why would I do such a thing? I'm parked!!! You headcases at TFL may have the money to burn in such fashion, most of the rest of us certainly DO NOT!

Now for this bit, and in line with Chris's thread, "If you know you are going to be stationary for more than a minute, turning off your engine will reduce harmful emissions.
If I were to follow this advice, I would be turning off my engine every couple of hundred yards. I can usually reckon to be stationary in London for more time than moving.

For example, if I leave home at 5.30am I can be at Earl's Court in around an hour; leave at 6.30am and the same journey may take in excess of 2 hours. If I were to turn off my engine every time I stopped for more than a minute, would I actually use more fuel than leaving the engine running? Starting the engine uses more fuel than continuous running and constantly turning off and on the engine puts greater wear on the battery and results in 'coking' of the engine, which in turn, leads to reduced efficiency and greater emissions.

Could I also ask why TFL are wasting money on this sort of rubbish and not sorting out the real problems faced by London's ever increasing traffic volumes?
« Last Edit: 11/01/2012 13:14:39 by Don_1 »


 

Offline Sprool

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Re: Should I turn off my engine?
« Reply #1 on: 11/01/2012 15:34:47 »
Lol - did you think he's supporting leaving the engine running when you're not in the vehicle? I didn;t get that impression from the post, its just if you are parked, waiting, in traffic, etc. not when you've popped into a shop or an office !
 

Offline peppercorn

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Re: Should I turn off my engine?
« Reply #2 on: 11/01/2012 15:42:13 »
I got the email too!

However, (and maybe I'm being naive here, but) can we take it as read that there is probably some husk of truth behind this poorly communicated message?

Similar to the earlier communique from the TfL overlords (about remaining in gear whilst slowing in traffic etc) I expect that it may be that this is true for some (or even the majority) of the situations.  So, a guide suggesting that - after a minute of idling the balance of fuel used outweighs that which is saved otherwise - is about right on average.  - Yes, some additional fuel is consumed for a re-start, but actually very little - esp. on modern engines.

I've been hearing the line that 'a big lump of petrol is used up during starting/restarting' ever since I was first driving [many moons ago] but I suspect that whilst it was most likely true in the days of carb'd engines and no ECU, whether it is still the case to anything like the same extent seems somewhat less likely IMO.


On the other hand, as you suggest the additional wear on components might offset these small efficiency gains through the increased need for maintenance and replacement of parts.  I assume at least one of their supposed motivation for this advice is to reduce CO2 emissions (as well as pollutants) in the capital, but again it is highly questionable if anyone in government has bothered to do a full cycle analysis on this (including vehicle wear).

For some reason I'm guessing the dent to one's wallet resulting from more frequent visits to the garage is probably not high on TfL's agenda however!!
« Last Edit: 11/01/2012 16:02:11 by peppercorn »
 

Offline Don_1

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Re: Should I turn off my engine?
« Reply #3 on: 11/01/2012 16:17:34 »
Lol - did you think he's supporting leaving the engine running when you're not in the vehicle? I didn;t get that impression from the post, its just if you are parked, waiting, in traffic, etc. not when you've popped into a shop or an office !

You need to hear the radio ad to pick up this. Can't find it on the www though.
 

Offline CliffordK

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Re: Should I turn off my engine?
« Reply #4 on: 11/01/2012 19:28:17 »
Personally, I think one should shut off the engine when stopping at stores, rest areas, and the like.  I also tend to shut it off when waiting for trains.  Oh, and at fast food restaurant drive-throughs, I think it is just polite to turn off the engine, both for noise and fumes.

I don't know about traffic.  I suppose in a NYC type gridlock, one might as well just shut off the engine and get out and push!!!  That has the added benefit of separating the driver from the horn button.

I presume that shutting off in normal traffic would be of minimal benefit, and the starter would wear out faster.  I tend to restart my engine (after a train) at the last possible moment, but then get anxious as the traffic starts moving and my engine is still off.

Anyway, the "Blue Motion Technology" and the Hybrids manage this for a driver, and I presume all have more robust starter systems.

I wonder if one could put a clutch between the flywheel and the engine, and use the flywheel to restart the engine?
 

Offline Mazurka

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Re: Should I turn off my engine?
« Reply #5 on: 12/01/2012 10:30:06 »
This is driven by the risk of (£300million)  fines from Europe for failing to meet air quality targets.  As Bozza did not want to extend the congestion charge zone and low emissions zone,  thinner straws are being clutched at...
I agree that there are some technological fixes - such as hybrids and "blue motion" technologies  - that could help, but these are relatively new to the market  (as comapred to the averagte age of motor vehicles on the road) and the benefits of these will take time to take effect.

Ban cars and extend the sewer trains?
 

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Re: Should I turn off my engine?
« Reply #5 on: 12/01/2012 10:30:06 »

 

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