Welsh government changing residential 30mph zones to 20mph

[V]

https://gov.wales/introducing-20mph-speed-limits-frequently-asked-questions

 

Proving that they are morons that cannot do simple maths...

 

Sent to Welsh AM:

 

Most internal combustion engined vehicles produced since the second world war with transmissions that have four or more gear ratios will be geared so that 1:1 ratio is typically 4th gear in a 4-speed or 5-speed transmission.

If a vehicle cannot sustain steady drive-ability at 30mph in 4th gear, a lower gear is required to keep engine RPM sufficiently high enough to prevent stalling the engine.

An approximate guide for most vehicles is 40mph in 4th, 30mph in 3rd, 20mph in 2nd gear.

Consider the following example:

If a 40 mile journey for a car travelling at 40mph takes 1 hour, the same 40 mile journey at 20mph will take 2 hours to complete.

Knowing that the use of 2nd gear in a transmission makes driving at 20mph possible at the same minimum engine RPM to avoid engine stalling, an extra hour of engine revolutions is required for the same 40 mile journey. That extra hour consumes fuel that would not otherwise be consumed driving at 40mph at the same engine RPM.

Therefore driving at 20mph increases CO2 emission for the same journey by 100% when compared to 40mph.
Driving at 20mph increases CO2 emission for the same journey by 50% when compared to 30mph.

To comply with the CO2 budget reductions towards 2050 as set in the Environment (Wales) Act 2016 the speed limit should really be increased from 30mph to 40mph or even higher where safe to do so to enable vehicles with 6 or more speed transmissions to benefit from the fuel economy gains of using their overdrive ratios.

Local councils and NHS will very quickly prove my point empirically because the number of litres of fuel they need to purchase will increase by 50%. The increase cost will have nothing to do with the price of fuel, this is the actual quantity in litres that they will need to buy.

For those foolish people claiming fuel expenses, they will lose out. Their compensation will remain the same being mileage based, but their actual fuel economy could drop by as much as 50% leaving most of them out of pocket.

It does not make any difference if the vehicle has a manual transmission or an automatic transmission, as soon as the journey requires gearing with mechanical advantage, wheel speed drops for the same engine RPM.
 

Edited September 10, 2022 by V
Changed title from 'all' to 'residential' to reflect government's claim of scope

[TimC]

Whilst all of that may be true Vince, the stated aims of the change do not appear to include either reduction of CO2 emissions or the saving of fuel. It would seem that is a price the Welsh government is willing to pay. 

[Raakhee]

The reduction of the speed limit is to account for the ever increasing mobile toting zombies who don't watch where they are going. 

Carbon/Nitrous emissions not taken into account here. 

[V]

The Environment (Wales) Act 2016 does not permit increased CO2 emissions between 2016 and the Welsh government's 2050 target. So attempting to bring in a new law that can be proven mathematically to increase CO2 (assuming mileages stay constant) would possibly expose the government to prosecution from environmental groups.

 

I have a 20mph road near home that half of my journeys go down. Getting caught on camera doing 30mph in a 20mph is a year's driving ban for most - Katie Price excepted of course. I stick to the 20mph limit and often get overtaken by someone accelerating to 40mph to pass me. I just don't see the point in such ridiculously slow speed limits that are very difficult to keep to often resulting in me rumbling along as slow as 15mph too make sure I have enough time to react to the hysteresis of my speed due to my Jeep having a human based speed control system.

[V]

12 minutes ago, Raakhee said:

The reduction of the speed limit is to account for the ever increasing mobile toting zombies who don't watch where they are going.

Fortunately, outside of cities, the zombies are few in number in rural Wales due to poor mobile reception.

 

Some councils got rid of diesel school buses to save money. They went from having one diesel engine transport 53 kids to school to 20 to 50 vehicles doing similar journeys. Now all of those school runs are going to take 50% longer and cost 50% more in fuel. Parents not only have to leave earlier to get to school in the morning, but they will also have to leave work earlier in the afternoon to fetch their kids. I reckon accidents will increase as more drivers are under time pressure to be somewhere else and they can't do more than 20mph.

 

Some kids will have to be dropped off earlier in the morning to wait outside school before it is open so parents can get to work as their onward journey takes longer at 20mph. The same in the evenings, having to wait longer for their parents to collect them. I wonder how many kids are exposed to danger through that decision.

[Gerald F]

You will find that 20mph limits are increasingly common in Scotland, too. Most town centres, and many residential areas have them, even on major routes such as the A7. Every school has a 20 limit whenever the crossing warden is present, as well. It's just about safety for pedestrians. 

The clean air efforts, however, are quite stupid; in Aberdeen, an important route to the harbour is now an LEZ, and the only alternative is a long drive through residential streets. This means shoppers and office workers have less exposure during their intermittent visits to the town centre, but those living roundabout have continuous increased exposure. The City Council said they thought the town centre was more important, but then, the shopping in that town is dying away, and the offices closing, so perhaps they hope for better trade at the expense of the inhabitants' health!

[UKTJ]

The title of this thread is incorrect.  The second FAQ linked to says:

 

”Will this affect all roads that are currently 30mph? 

The change in legislation will only affect residential roads and busy pedestrian streets. We are working closely with highway authorities to identify potential roads where speed limits will be reduced to 20mph and those which should remain at 30mph.”

[digger]

I don't like it either for all the reasons stated.

However , in my opinion, this approach has been caused by the small number (10%?) of drivers who persist in driving like lunatics with no consideration for others. in response the often non driver bureaucrats come up with proposals like this.

I live in a small urban area which is a 20mph zone. Its not rocket science to see why!  Lots of parking ,nearby shops, schools etc.etc.  It never ceases to amaze me how some ''people''(morons) seem to be oblivious to everything except their apparent haste. Whilst some are, the majority are not ' 'boy racers' they are ordinary looking folk of many ages. I have to mention the awful stress/pressure that many seem to live with today!

Only yesterday, I saw a car being driven at, I believe between 50 and 60mph along our road!  ''Ah , he doesn't know what he's talking about!'' .  Well ,I think I do, having spent over 50 years around race tracks watching, timing all kinds of machines. I certainly know when something is going very fast!!

Of course , no police (too expensive and no time), no cameras (they don't collect enough tax in places like this and of course don't forget Wales is the place if you want to be caught by hidden (inaccurate) cameras with strict speed compliance), no anything!  We normal ,sensible folk just have to suffer a blanket 20mph which I've been warning would come for a few years now, but then, I'm just a dinosaur!

 

Edited September 10, 2022 by digger

[V]

7 hours ago, UKTJ said:

The title of this thread is incorrect.

I have changed the title from 'all' to 'residential' to match the government's claim of scope as pointed out.

 

As a high proportion of 30mph roads in Wales include residences, the claimed scope has the potential to make 20mph the most common speed limit in Wales. Industrial estates being the only other common 30mph zone without residential properties. The Environment (Wales) Act 2016 still makes it illegal for council's to increase CO2 emissions which this scheme will do.

[digger]

Interesting V.

Some years ago they made our town centre pedestrianised plus a lot of new 'one way' roads and buses only roads, I did a couple of calculations at the time and found that a number of destinations for me had considerably lengthened. In one case I seem to remember that a journey of one mile had become three! I agree,  so much for being concerned about emissions!

[Surfer]

Many town centres that became pedestrianised seem to be dying with the High Street being full of charity shops who apparently do not pay council tax while out of town shopping centres with plenty of parking are thriving and doing a booming business!  Says it all!