HSTEd
Veteran Member
- Joined
- 14 Jul 2011
- Messages
- 16,840
It will probably depend if the magical batteries they are hoping for actually appear in the next few years.Government's gone extremely quiet on this - I personally think this will not happen in the UK because
- we lack true long-haul road freight of the kind you see on Mainland Europe & North America
- it's starting to look like the majority of HGV mileage in UK can be covered by battery electric with charging at depots etc.,
- Government (at least the one we have) lacks the appetite for this kind of public sector investment
If it doesn't, eventually they will panic and place the order for the eHighway scheme, or more likely try to apply ever increasing fudges to the budget.
By the same token, they aren't going to provide the billions in additional subsidies required to significantly expand rail freight operations as a tool for decarbonisation.
Age and weather-related degradation is probably a significant fraction of road repair cost though, especially on secondary roads that consume a lot of the budget.Stress on roads from vehicles is a function of a 4th power law. Some beermat maths:
Car estimate 1,500 kg, so 750 kg per axle
HGV might be 44 t on 6 axles, so 7,300 kg per axle
A difference of about 10 times. The 4th power law means that 10 times the weight leads to 10,000 times more road stress (and damage).
It also matters how far vehicles are driven. According to DfT stats at https://roadtraffic.dft.gov.uk/summary the figure for cars is 244 billion vehicle kilometres, whereas for HGV it's only 17.4 billion vehicle kilometres.
However, if each HGV km is 10,000 more damaging, then the relative damage to the highway is comparable to 174,000 billion vehicle kilometers travelled by cars. 244 is <0.1% of 174,000...
Now there's a lot of estimates here, but I think it's basically saying that nearly all road degradation not from age-induced decay or materials, vegetation or botched streetworks repairs is probably down to HGV.
It also assumes that damage repair costs (or indeed overall road spending) are entirely linear with respect to a "damage" parameter, which is probably a bad assumption.
A very large fraction of HGV traffic is on the Strategic Road Network, and thus must cost no more than £5bn given that's what the entire SRN costs.
There doesn't seem to be much evidence that there is some enormous hidden subsidy to road freight operations.
Or they are just charging what they believe people in a hurry would pay to avoid the congestion on the real M6....The M6 Toll operators know all about the fourth power law. So that price is set to a point that deters the majority of HGV traffic. There is probably a tipping point price below this where it would suddenly start to look like good value for HGV operators, and costs (from road damage) would increase much faster than revenue. Set it much higher, and suddenly people like regulators start getting interested and they don't want that.
However, I realise we are wandering off topic so we should probably stop.
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