Skip to content

Electrification of road freight using overhead cables

July 30, 2021

By Paul Homewood


From GWPF:




Putting overhead cables on just motorways and dual carriageways could cost around £58 billion (the basis of this figure is set out below). It will be practically impossible to install overhead cables on most of the rest of the 31,800 miles of the major road network. If the freight fleet is to be fully electric, lorries would therefore have to rely on on-board batteries in places where they cannot be charged by the overhead cable.

Electrifying the freight fleet would require a major expansion of electricity generation capacity. Assuming this comes from from wind power, 22 GW of new windfarms would be needed (assuming an improved capacity factor of 0.4) supported by sufficient storage capacity. Detailed calculations are set out below. This new capacity is likely to cost over £88 billion and there would be significant ongoing operating costs. For comparison, total wind capacity in 2019 in the UK was 24.1 GW.

Energy supply to the trucks would have to be guaranteed at all times. This will mean that electricity generation from natural gas has to be retained for when the wind was not blowing. The alternatives – battery storage or nuclear – are prohibitively expensive or are politically unacceptable.

The total capital cost could therefore be £130–150 billion, and there would be significant ongoing operating costs.

Honest life-cycle analysis is needed for all the alternative approaches. This should include greenhouse gas (GHG) contributions from the electricity used for running the lorries, manufacturing and the end- of -life disposal/recycling of batteries and installing the infrastructure. Running long-haul transport on electricity alone will certainly not be a zero-GHG solution even with increasing decarbonisation of the electricity supply. If the battery capacity needed is large, even after some of the electricity is taken from overhead cables, such an approach could have minimal or even negative impact on GHG emissions compared to using advanced diesel engines.

Detailed calculations and considerations


There are 31,800 miles of major roads (2,300 miles of motorway and 29,500 miles of ‘A’ roads) in Great Britain.1 Dual carriageways account for about 17% of A roads2 so there are around 7,315 miles of dual carriageways and motorways.

Electrification of the rail network has taken decades and offers some guidance about the costs. However, there are great practical difficulties in installing overhead cables on roads compared to railway tracks:

  1. Normal A-road verges are not secure, unlike railway lines, and so a different and more expensive electrical supply cabling will be required.
  2. Bridges on the road network limit the overhead clearance.
  3. Managing the power supply to the overhead cables will be challenging. For instance, unlike on the railways, there could be several lorries on a steep hill drawing electricity. This draw would need to be limited to avoid overloading or burning the overhead cable.

Complex electrification projects on the railways have cost up to £2.5 million per km of single track.3 So, installing cables on both sides of the road could cost up to £5 million per km. Hence, installing overhead cables just on the motorways and dual carriageways could cost £58 billion.

Additional electricity generation

The UK HGV fleet’s fuel consumption is around 12 million tonnes pa (140 million MWh).4 Assuming an average brake thermal efficiency of 0.42 for modern diesel powertrains,5 59 million MWh actually gets to the wheels and this has to be supplied by electricity, some of it from overhead cables. However, up to 10% of electricity is lost in transmission and distribution in the UK.6 A further 5% of the energy is lost in converting the overhead AC power to DC and typically another 10% in the DC motors. The result is that only around 77% of the electricity produced is available at the wheels. So, to supply 59 million MWh, 77 million MWh of electricity needs to be produced on average. This is equivalent to 8.8 GW of continuous power generation on average, equivalent to three Hinckley Point C nuclear reactors at around £25 billion each.

The capacity factor for wind in the UK, averaged over 2019 was 0.3 – the installed wind capacity of 24.1 GW, if it had worked continuously at rated capacity, should have supplied 0.76 exajoules, but actually supplied only 0.231 exajoules7 on average. Assuming a much-improved capacity factor of 0.4, new wind capacity of 22 GW has to be built to supply 8.8 GW needed on average. Assuming a capital cost of £4 million per MW, the capital cost of this new wind installation alone could be around £88 billion and the operating costs also would be extremely high.8 The excess electricity that will be produced from time to time can be used to produce hydrogen or electro fuels or stored in batteries. Providing this “storage” capacity will add further to the costs.

In any case, the power supply to the HGV fleet has to be guaranteed at all times and hence has to come from baseload electricity, and needs to be dispatchable, so as to quickly adapt to any changes in demand. Baseload electricity is usually produced from fossil fuels, so taking this path to power long-haul transport will not get rid of electricity generation from natural gas. The actual CO2 benefit will be less than assumed with zero-CO2 electricity. The only alternatives are:

  • electricity storage, such as batteries, but this would add significantly to the costs
  • new nuclear capacity, but this could cost £75 billion.

Honest life-cycle analysis is needed for all the alternative approaches. This should include greenhouse gas contributions from the electricity used for running the lorries, manufacturing and the end- of -life disposal/recycling of batteries and installing the infrastructure. Running long-haul transport on electricity alone will certainly not be a zero-CO2 solution. If the battery capacity needed is large, even after some of the electricity is taken from overhead cables, such an approach could have minimal or even a negative impact on greenhouse gas emissions compared to using advanced diesel engines.

  1. Peter Barrett permalink
    July 30, 2021 11:37 am

    I really can’t see any problem with this at all. Why is everyone so negative about it? We could even take it a step further and install some sort of tracks or tramway on the motorway for the lorries to run along. Perhaps we might give it a name – I don’t know – something like a “railway”. What a great idea, should I try to copyright the name? I’m sure nobody has thought of it before.

    Incredible. Fantastic. Literally.

    • July 30, 2021 12:11 pm

      Lunatic! Will the authors of the suggested scheme come forward and own up once they have got out of standing in the corner, the mildest, most humane punishment in their primary school!

    • Ben Vorlich permalink
      July 30, 2021 1:20 pm

      You’d end up with trains of lorries all following the slowest and unable to pass. On the plus side it would avoid the situation where one lorry doing 58 mph passes one doing 57 mph. A process that can take 4 or 5 minutes and cover a distance of 5 or 6 miles. That’s assuming a hill doesn’t get involved.

      • David Wojick permalink
        July 30, 2021 2:39 pm

        The plan calls for them to pass by disconnecting then reconnecting back in the slow lane. A problem of its own.

      • Russ Wood permalink
        July 31, 2021 4:13 pm

        Ah! I see you have also been driving on South AFrican major roads!

  2. Adrian Wingfield permalink
    July 30, 2021 11:53 am

    Am I dreaming or is this real??? This sounds completely bonkers to me. Quite apart from the costs of installation and maintenance, the question of supply of sufficient electrical power and the very obvious safety implications, what happens when a catenary cable is inevitably damaged. We are all aware of the consequences in respect of railways ( “…delays due to overhead line problems…”). Perhaps I’m just being negative!!!?

    • David Wojick permalink
      July 30, 2021 2:40 pm

      Imagine when an ice storm brings a live cable down on a km of busy highway!

  3. David permalink
    July 30, 2021 11:57 am

    It would be better to install induction coils under the road surface with pick up coils under the vehicles very close to the road surface and supported by a hovercraft type air flow system. This would be cheaper to maintain, less unsightly and could be used by all vehicles so equipped.

  4. tomo permalink
    July 30, 2021 11:58 am

    In a field full of squawking Polyannas and Panglosses – most actual questions are carefully curated behind firewalls.

    Unless it’s Iceland

    The Telegraph on the electricity crunch – Vampire EVs

    • tomo permalink
      July 30, 2021 11:59 am

      bah… paywalls – damn these text correctors….

  5. Dick Goodwin permalink
    July 30, 2021 12:04 pm

    Great idea until you want to change lanes, go into the Motorway Services or breakdown with other lorries close behind you. The cables would have to be high voltage (as on the railways).

    Where would the control equipment go as in the transformer (extra weight) and the retifier?

    How large would the battery need to be to start the engine when not connected to o/h line?

    Where would this battery go?

    What would happen when a HGV(s) had to stop in a neutral section such as a traffic jam or an accident. How would it start again?

    What would happen if the overhead lines were bought down in an accident. Would these just be motorways for HGVs or would cars run along side them.

    How would you get a wide or oversized load on the motorway if you had high voltage cables above you.

    Yes, a great idea.

  6. July 30, 2021 12:07 pm

    We used to have a system of delivering freight long distances and in bulk.
    It was called the railway.
    Remember those?

    • Cheshire Red permalink
      July 30, 2021 12:27 pm

      It’ll never catch on.

      • July 30, 2021 6:20 pm

        The Greens have ways of making it catch on, like other examples of madness!

    • David Wojick permalink
      July 30, 2021 2:45 pm

      Railways neither pick up nor deliver freight. That is done by trucks.

      • July 30, 2021 7:43 pm

        The point of break of bulk is something you may have missed in school lessons.
        It is a particularly important feature of island geography and trade routes.
        BTW The length of the M6 motorway is 230 miles, maybe that is just a local delivery distance for the modern truck?

  7. Cheshire Red permalink
    July 30, 2021 12:26 pm

    Has our entire political class been eco body-snatched, or merely lobotomised?

    These plans disregard costs as irrelevant and will have NO positive impact on anything worthwhile. They’re also stuffed full of unintended consequences, just waiting to wreak havoc on our country. Giant government infrastructure projects always are.

    At some point sane voices in Parliament must step forward and whisper calming words into a certain someone’s ear, or maybe the men in white coats will be discretely summoned?

    This madness cannot continue unchallenged. Steve Baker MP is one to have raised public concerns, although others will certainly be sceptical in private.

    This madness has to be stopped.

  8. Robert Christopher permalink
    July 30, 2021 1:28 pm

    What will happen to the ‘Smart’ Motorways?

    Will this upgrade (if it can be called that 🙂 ) occur in the left-hand lane, where broken down vehicles are usually to be found if they cannot make to a layby?

    Is there a EU equivalent? If so, will the specifications be the same? 🙂

    And I hope that this will be implemented, as they all are, in one gigantic phase, as it’s so urgently needed, with no ‘lessons learnt’, as that would scupper the whole thing!

  9. Ron Arnett permalink
    July 30, 2021 1:36 pm

    This has the same problem as all the other electrification plans. Leaving aside the power generation needed to replace all existing petro energy, there is the problem of the grid.

    If you plan on doubling or tripling the capacity of a grid that took a hundred years to put in place, you are not going to get it done in a ten year period. Or at least not with a wave of the hand assumption that all these green new deals employ to deal with the reality of power distribution.

  10. bobn permalink
    July 30, 2021 1:40 pm

    Then of course this huge extra demand for electricity will be supplied by ……..

  11. Nicholas Lewis permalink
    July 30, 2021 2:11 pm

    Rather than wasting money on this madness they need to spend it on electrifying more of the railways like the Felixstowe branch whence significantly more of rail traffic could then be hauled by electric locomotives that already exist.

    • In The Real World permalink
      July 30, 2021 3:14 pm

      They did spend about £100 Million on upgrading the 10 miles of rail line between Felixstowe , [ UKs biggest container port ] and Ipswich .
      And thousands more containers per week now go by rail .
      The end result is that now about 6% of goods movements in the UK now go by rail , and still over 90% are on the roads .

  12. Joe Public permalink
    July 30, 2021 2:32 pm

    Oh no, the GWPF has sunk to the level of ocean heat-content scaremongers!

    Their piece started off OK, using units most folk are most familiar with e.g. MWh & GW.

    Then we read:

    “The capacity factor for wind in the UK, averaged over 2019 was 0.3 – the installed wind capacity of 24.1 GW, if it had worked continuously at rated capacity, should have supplied 0.76 exajoules …”

    WTF – why introduce (exa)joules when Watts have already been used in the same sentence?

    Quick couple of mental questions to all readers – (no calculator or Googling permitted):

    “What’s the average heat & power consumption of a medium-sized ‘normal’ home, in (exa)joules?”

    “What’s the rating of your kettle, in joules?”

    Few folk have a perception of joules; no one’s (UK) energy bill is based upon joules consumption; no one (in UK) buys their energy by the joule.

    No doubt Paul’s above-average energy-intelligence readers will provide a few correct answers, but here, there are more above-average energy-intelligence readers.

    • Ray Sanders permalink
      July 31, 2021 10:56 pm

      Yep I spotted that as well. Truly weird, why not throw in calories or BTUs just to really confuse everyone. I recall reading recently that less than 10% of the UK gas bill payers actually knew how to calculate their useage from meter readings. Sad.

  13. David Wojick permalink
    July 30, 2021 2:55 pm

    I have an article coming out on CFACT that in part explains this nonsense to Americans. There is the truck part:

    “But if you think this is weird, take a look at what the Brits are planning for big trucks. Their proposed way of making heavy trucks electric is to run them via overhead wires, at least on the main highways. Still not making it up. Critics are calling them “truck trolleys” and with good reason.

    Imagine having hot wires strung just above all the nearly 50,000 miles of interstate highways, carrying enough juice to power all those big trucks. Massive accidents waiting to happen? How about them ice storms?

    Seems like the wires will only run over the slow lanes, so maybe just 100,000 miles worth. So to pass or run in the fast lanes the truck disconnects then connects again when it gets back in the slow lanes. Hopefully the driver does not have to participate.

    I guess they run the trucks on batteries part time, including when the big rigs leave the big roads. The Brits are ahead of the Americans when it comes to climate craziness, so maybe we have this weird one to look forward to.

    The problem is that while a car full of people is light, a trailer or two full of freight can be very heavy. We run a lot of two trailer tandem rigs. So running big freighters on huge batteries does not work. Nor can the truckers sit around for hours waiting for their big rigs to charge. The green American governments have yet to address this wacky problem.

    No word in either case, CAFE or truck trolleys, on where all the juice is going to come from. We are talking about an enormous amount of new around-the-clock generating capacity. Highly intermittent wind and solar do not do the job.

    If you think subsidized wind and solar power are stupid, wait until they start trying to forcibly electrify car and truck travel. From an engineering point of view 2030 is now.

    EV weirdness looms large.”

    • MikeHig permalink
      July 30, 2021 4:14 pm

      You might want to update your article with a look at what is going on in Germany: they are well ahead of the Brits with this idea. They actually have a section of autobahn fitted out with catenaries. There is a small fleet of prototype trucks testing it all out.

      • David Wojick permalink
        July 30, 2021 5:04 pm

        Yes I know but I had no room for it or information on it. Testing is harmless; planning not so much.

      • Lez permalink
        July 31, 2021 7:27 pm

        That’s all very well, but there are currently 30 coal-fired power stations in Germany, accounting for around a third of its electricity generation.
        They may just as well use steam lorries.

  14. Edward Martin permalink
    July 30, 2021 3:01 pm

    Doesn’t seem at all feasible for highway trucking but in the 1950’s the electrically driven city bus lines in Milwaukee seemed to work quite well

    • July 31, 2021 5:12 am

      You don’t know that almost all UK cities used to have trolleybuses ?
      but they all got abandoned cos diesel buses could go everywhere.

      There’s probably some countries that still have them, maybe in Australia.

      • Russ Wood permalink
        July 31, 2021 4:18 pm

        When I was last in New Zealand, the capital Wellington, still had trolleybuses.

  15. europeanonion permalink
    July 30, 2021 3:20 pm

    It is just a battle of wills and the assertion of power over democracy. A tyranny. Meanwhile if the government could use engineering to lower the number of traffic queues and actually increase average speeds a huge tranche of the pollution of which they speak would prove to have been an infrastructure problem. Sealing-off streets does not diminish pollution only concentrates the overall pollutants and being denser probably becomes harder to shift.

    I believe that dirigibles are an answer to our human transportation problem. Balloons on zip wires would be an excellent way of servicing commuting, especially in a high-rise environment. When you think of flying cars you are also think about high standards of piloting required and there is no way of pulling-over should your flying vehicle fail. Dirigibles on wires could have programmable destinations with no strike fodder (unlike HS2, which is a godsend to the trades unions).

  16. Lorde Late permalink
    July 30, 2021 3:37 pm

    If my father was still alive he would be pleased, it would remind him of the trolley buses of his childhood. Removed as I recall because better more flexible technology came along!

  17. Giveusabreak permalink
    July 30, 2021 6:10 pm

    It reminds me also of the trolley buses of my childhood. Replaced in the 60s because they were impractical as road traffic increased. The conductor used to have a big pole to put the connector rods back when they fell off – as they did frequently. It is barmy enough electrifying railways with overhead lines – when we could be using hybrid trains with batteries charged from a switched third rail system which would be an order of magnitude cheaper. If they had another brain it would be lonely!

  18. Emma Richey permalink
    August 4, 2021 7:09 pm

    They just keep coming up with more and more ludicrous ideas

Comments are closed.

%d bloggers like this: