Speed Awareness Course

[Lons]

I agree that a lot of tourists stay in rented cottages, but having in my youth had to rent places, I can assure you those make a difference too. If those homes were rented out on long lets, there wouldn't be the scramble every spring, when "winter lets" suddenly throw out their tenants, causing a huge number of people to compete for the small number of properties available. There should be no such thing as "holiday homes" - either you rent the house out long term or you sell it. Tourism would still survive by using the alternatives you mention.

I absolutely agree, there are many areas around here where locals are priced out of the market for similar reasons.
We suffer from increased traffic congestion as well especially so from European cars heading through and on to Scotland, but I'm sure the Europeans say the same about English tourists.

 

[paulrbarnard]

I absolutely agree, there are many areas around here where locals are priced out of the market for similar reasons.
We suffer from increased traffic congestion as well especially so from European cars heading through and on to Scotland, but I'm sure the Europeans say the same about English tourists.

Slightly different where I live as we are in commuter distance of a city and that has resulted in a lot of city workers moving in to the village. No where near as bad as holiday homes but still has the effect of driving up the prices for those who live and work in the area.
There is a lot to be admired in the 15minute city concept. Though the majority of motorists seem to believe that’s a personal attack on driving.

 

[Agent_zed]

Far be it from me to agree with a petrol head but apparently Lons might be correct.
It's obvious really - at zero mph with an engine running you are getting zero miles per gallon. As you speed up the energy needed to run the engine itself is still greater than that needed to shift the car, up to a point, according to the whole vehicle design.
But it isn't the issue so Lons is missing the point anyway .
I was surprised by this graph too: Mpg For Speed - Fuel Efficiency Vs. Speed

I think there is far more to this than the graphs show. It depends what they are measuring and it is not clear from the graph or text what the parameters are.
For example the graph on here Fact #982: June 19, 2017 Slow Down to Save Fuel: Fuel Economy Decreases About 14% When Traveling at 70 mph Versus 60 mph shows a clear decrease in mpg between 40-50 which is completely the opposite for the graph that was posted.

If the mpgs take into account the average driving conditions then I would be more inclined to believe it. E.g 25mph average is likely to be on small windy roads with lots of stop and start. 40-50mph is going to be larger smooth roads. Nothing to do with the actual car and engine per say.

I don't have time to investigate further but I cannot feasibly see how a car doing 20mph on the same road would use more than a car doing 40mph.

Maybe if I am very bored and have time I'll test my car as I have to go through a lot straight industrial area (I won't make a special trip just the next time I need to go through).

 

[Phil Pascoe]

There is a lot to be admired in the 15minute city concept.

Yes, if new cities are designed for it.

 

[Phil Pascoe]

Cornwall doesn't suffer too much from heavy traffic outside of holiday times and holiday areas, but if my wife leaves for work later than 8 am it takes her an hour and a half to do the eleven miles. Just to add to the joy they're building at least new 4500 houses between here and there.

 

[sploo]

Can't disagree with that.

I'd even go further and say travelling at 20 mph all day would consume less fuel than doing the same at 30mph, IF the car was geared correctly. Unfortunately cars are set up to run economically at higher speeds.

Yep. I don't know at what speed the major load goes from friction in rotating components (internally, or tyre to road) to wind resistance; and it'll be different for different cars. But yes, a constant 30mph should use more fuel than a constant 20mph. A constant 10mph vs constant 5mph... dunno.

 

[Agent_zed]

Yep. I don't know at what speed the major load goes from friction in rotating components (internally, or tyre to road) to wind resistance; and it'll be different for different cars. But yes, a constant 30mph should use more fuel than a constant 20mph. A constant 10mph vs constant 5mph... dunno.

it's around 50-55mph. Wind resistance becomes the major factor. You can see the change on this Fact #982: June 19, 2017 Slow Down to Save Fuel: Fuel Economy Decreases About 14% When Traveling at 70 mph Versus 60 mph around 50mph the increase in fuel consuption increases at a different rate.

What's annoying is that the law hasn't caught up yet and allowed for cameras instead of wingmirrors. There is a 2-6% increase in drag from wing mirrors that could easily be lost by using form fitting cameras https://www.sciencedirect.com/science/article/pii/S1110016821004129

 

[porker]

Isn't the point though that travelling all day at 20mph doesn't get you as far as travelling all day at 30mph (actually one third less). The point is that it's miles per gallon that they are showing not gallons per hour. Cars are geared as said before to give maximum mpg at a particular speed. I would guess this speed is around 56mph because that is what the manufacturers quote to show the best possible number.

Also at speeds below about 50mph, the weight of a car has more effect than the aerodynamics, so low speeds like 20-30mph I would guess would have a small aerodynamic effect

 

[bilspe]

Cornwall doesn't suffer too much from heavy traffic outside of holiday times and holiday areas, but if my wife leaves for work later than 8 am it takes her an hour and a half to do the eleven miles. Just to add to the joy they're building at least new 4500 houses between here and there.

I would argue even outside the holiday season the main routes around Cornwall have increased considerably in traffic, but then that applies to traffic in general.
And whats all this I keep hearing in the media that we're not building enough houses ? Cornwall is becoming one big building site !

 

[Terry - Somerset]

Staying in a gear beyond the point at which the car is capable of using a higher gear means maintaining higher engine speeds which must have a consumption penalty. Conceptually:

Based on the above simplistic model, - on a motorway optimum speed would be ~55mph in 6th gear. In town at 20mph in 2nd gear would be optimal.

As different cars have a different number of gears, and different power/torque curves there is no one solution. For instance should one accelerate from (say) 24mph in 2nd gear to (say) 26mph to allow 3rd gear to be taken despite the increase in wind resistance.

Lessons could be ;learned from those who engage in hypermiling. Aside from common basic "tricks" - eg: maintaining vehicle properly, tyre pressures, minimising unnecessary weight, two things stand out:

• anticipate and avoid braking which turns expensively won speed into heat
• change to the highest gear that the speed of the car will support
• accelerate gently

 

[Terry - Somerset]

As a hypothetical thought - what would be the consequences of banning 2nd home ownership in (say) Cornwall.

The price of property would fall, no longer buoyed by relatively wealthy weekenders and holiday rentals. Some local businesses would suffer - pubs, restaurants and leisure, reducing local jobs.

Stable communities need jobs and local wealth creation. There are two obvious alternatives:

Small towns and villages often become feeders for jobs in nearby larger urban areas. This would keep local schools and other facilities open but at the expense of mass commuting.

• for Cornwall possible large urban areas may be limited to Plymouth and Exeter (in Devon)
• smaller towns in the county do not generally offer a wide range of well paid careers (eg: in consultancy, major hospitals, universities, science parks, technology etc)

The alternative is to attract higher value businesses to more remote areas:

• most businesses thrive with good connectivity to customers and suppliers,
• need a broad labour market with high skills base
• there is evidence that innovation comes through interaction with a diverse range of other businesses stimulating ideas

None of this is generally plausible in more remote locations. Without local opportunities the young will be drawn to larger cities to develop a career, and often never return.

Much though the thought of property costs driving out locals is disliked, without wealthier second home owners and holiday rentals there may be no real demand anyway. Other remote parts of the UK where the sun doesn't shine and the scenery beckon are often seriously deprived.

The UK could easily follow the trend in much of Europe where increasing urbanisation has left rural communities the province of the impoverished and elderly.

 

[Agent_zed]

Staying in a gear beyond the point at which the car is capable of using a higher gear means maintaining higher engine speeds which must have a consumption penalty. Conceptually:

View attachment 167365

Based on the above simplistic model, - on a motorway optimum speed would be ~55mph in 6th gear. In town at 20mph in 2nd gear would be optimal.

As different cars have a different number of gears, and different power/torque curves there is no one solution. For instance should one accelerate from (say) 24mph in 2nd gear to (say) 26mph to allow 3rd gear to be taken despite the increase in wind resistance.

Lessons could be ;learned from those who engage in hypermiling. Aside from common basic "tricks" - eg: maintaining vehicle properly, tyre pressures, minimising unnecessary weight, two things stand out:

• anticipate and avoid braking which turns expensively won speed into heat
• change to the highest gear that the speed of the car will support
• accelerate gently

When I got my car it was about 5 years old. The average mpg reported by the onboard computer was 36mpg.

I drive mostly B roads and live in a relatively hilly part of the country but still managed to take this to a consistant 50.3mpg.

God knows how the previous owner used to drive to get it down that much. Being a diesel it tends to be best at low revs and I tend to drive between 1300-1800rpm to get the best return. The change up indicator also supports this range.

I still don't understand the people who shoot up to a red light and stop rather than think ahead and slow so I get there when it changes to green with momentum to keep going. Often get through the lights faster than the person who passed me on a two lane setup.

One thing that really helps me drive better is my dashcam. If you know that if you have an accident your own actions will be recorded and reviewed you think slightly more about your own behaviour.

 

[Spectric]

I absolutely agree, there are many areas around here where locals are priced out of the market for similar reasons.

Really bad in the Lake district, even cases of landlords getting rid of long term tennants to become air b and b's as they can charge a lot more but it has had an impact on local businesses who are now having problems getting staff with some only opening part time and others closing down. At the current rate it will become a rich persons getaway and maybe the only thing holding it back is getting planing for helipads !

 

[niall Y]

Here's a really naive question. - If an engine on a test bed runs for an hour and consumes a set amount of fuel, and then runs for an additional half hour I'm logically assuming that it will consume half as much fuel again - the difference between 30 and 20 Mph, So, is fitting this engine into a vehicle and test driving it at these two differing speeds really going to show that this difference in fuel consumption will disappear?

 

[Cobbs]

As a hypothetical thought - what would be the consequences of banning 2nd home ownership in (say) Cornwall.

The price of property would fall, no longer buoyed by relatively wealthy weekenders and holiday rentals. Some local businesses would suffer - pubs, restaurants and leisure, reducing local jobs.

Stable communities need jobs and local wealth creation. There are two obvious alternatives:

Small towns and villages often become feeders for jobs in nearby larger urban areas. This would keep local schools and other facilities open but at the expense of mass commuting.

• for Cornwall possible large urban areas may be limited to Plymouth and Exeter (in Devon)
• smaller towns in the county do not generally offer a wide range of well paid careers (eg: in consultancy, major hospitals, universities, science parks, technology etc)

The alternative is to attract higher value businesses to more remote areas:

• most businesses thrive with good connectivity to customers and suppliers,
• need a broad labour market with high skills base
• there is evidence that innovation comes through interaction with a diverse range of other businesses stimulating ideas

None of this is generally plausible in more remote locations. Without local opportunities the young will be drawn to larger cities to develop a career, and often never return.

Much though the thought of property costs driving out locals is disliked, without wealthier second home owners and holiday rentals there may be no real demand anyway. Other remote parts of the UK where the sun doesn't shine and the scenery beckon are often seriously deprived.

The UK could easily follow the trend in much of Europe where increasing urbanisation has left rural communities the province of the impoverished and elderly.

If the visitors are that wealthy, then why can they not afford a hotel? They'll be paying hundreds of thousands for the property, plus regular upkeep costs and everything else, when they could get a hotel or B+B holiday for much less. If they still want to buy the property, that's fine, they can rent it out and someone else will have a home, meaning that the town or village will have permanent residents to support local businesses and amenities around the year, not just for a few months of it. Meanwhile the owner pockets the rent money and can afford another holiday - where's the downside in that. If they are staying in a hotel, the money still goes to the local inhabitants and creates jobs along the way.

 

[paulrbarnard]

If the visitors are that wealthy, then why can they not afford a hotel? They'll be paying hundreds of thousands for the property, plus regular upkeep costs and everything else, when they could get a hotel or B+B holiday for much less. If they still want to buy the property, that's fine, they can rent it out and someone else will have a home, meaning that the town or village will have permanent residents to support local businesses and amenities around the year, not just for a few months of it. Meanwhile the owner pockets the rent money and can afford another holiday - where's the downside in that. If they are staying in a hotel, the money still goes to the local inhabitants and creates jobs along the way.

If they are that wealthy then they have no incentive to rent it out. That’s the problem. They aren’t looking for an income, just putting money in to a relatively safe investment that they can spend a couple of weekends in and brag about to their peer group.

 

[Spectric]

If an engine on a test bed runs for an hour and consumes a set amount of fuel

This would need to be a constant load with all parameters fixed, but it is far more complex with many parameters that will change fuel consumption and dyno's will run power curves to get everything maped to meet requirements and legislation on emisions. One of the reasons start-stop was introduced was to reduce pollution from stationary vehicles in traffic, but there is an engine speed / load range that is most efficient and outside of this has always been only a intermediate range to get from stationary to x mph and not always that clean so trying to maintain 20mph could be in a more polluting engine speed range than 30mph and in many cases running higher RPM in a lower gear. The end result is you spend more time passing through a town whilst delivering more pollution. Trucks could be even worse, especially if fully loaded.

 

[Jacob]

Really bad in the Lake district, even cases of landlords getting rid of long term tennants to become air b and b's as they can charge a lot more but it has had an impact on local businesses who are now having problems getting staff with some only opening part time and others closing down. At the current rate it will become a rich persons getaway and maybe the only thing holding it back is getting planing for helipads !

It started big time with the Highland clearances and has carried on ever since. Land is the big issue in terms of unequal wealth distribution.

 

[John Brown]

All townies should have to attend speed awareness courses before being allowed to buy property in rural areas.

Why is Terry - Somerset the only person who's worked out how to use bullet points?

 

[paulrbarnard]

This would need to be a constant load with all parameters fixed, but it is far more complex with many parameters that will change fuel consumption and dyno's will run power curves to get everything maped to meet requirements and legislation on emisions. One of the reasons start-stop was introduced was to reduce pollution from stationary vehicles in traffic, but there is an engine speed / load range that is most efficient and outside of this has always been only a intermediate range to get from stationary to x mph and not always that clean so trying to maintain 20mph could be in a more polluting engine speed range than 30mph and in many cases running higher RPM in a lower gear. The end result is you spend more time passing through a town whilst delivering more pollution. Trucks could be even worse, especially if fully loaded.

But it could also be the opposite, even the transit time if congestion is eased with smoother traffic flow. Easy to focus on hypotheticals that support a specific view.