Ronaldo47
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Posts posted by Ronaldo47
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The Green Marine plan document does mention that money would be spent on researching green energy propulsion.
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6 hours ago, Tony Brooks said:
I also note that you have not mentioned the refuelling problems that seem to have been found in, I think, experimental German trains. This may make things very difficult to use hydrogen for transport purposes.
This was reported in "Modern Railways" last year. One of the german regional railways had invested in a fleet of green hydrogen-powered trains, but found they couldn't be reliably refuelled at temperatures lower than minus 20°C, a common winter temperature in that part of Germany, so the original fleet of diesels had to be brought back into service. Apparently a german bus company had exactly the same experience. They replaced their new hydrogen-powered buses by new diesel-powered ones.
I guess it's not the sort of problem we would have in the UK, where it is rare to get temperatures that low.
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7 hours ago, agg221 said:
To illustrate my point, when towns gas was in use, why did both the hydrogen and the carbon monoxide reach intended destination, rather than the hydrogen being lost en-route?
Town gas was usually produced locally ( hence the name Town Gas?) in numerous relatively small gas works and distributed short distances at a lower pressure than natural gas, so loss of hydrogen by leakage or diffusion would have been less of a problem. There was no national gas network before the UK's conversion to natural gas, as there had been no need for one. Conversely, the national natural gas network was constructed to transfer natural gas distances of hundreds of miles, originally from a single storage terminal.
It is seldom remembered today that the original plan, devised by the former North Thames Gas Board, was to import cheap natural gas in liquified form from Algeria, using a fleet of tankers, to a terminal on Canvey Island in Essex, from which pipelines would extend via London to the Midlands and the North. Provision was made for a prospective second terminal on the Mersey for importing liquified natural gas from the USA. My late father used to work for North Thames Gas, and I still have a copy of an edition of the NTG staff magazine that describes and illustrates the scheme as originally conceived in some detail.
While the gas grid was still under construction, North Sea Gas was discovered, so the gas grid had to be redesigned to provide East-West connections from the East Coast gas terminals to join the originally-planned North-South pipelines.
Unless Hydrogen is to be generated locally like town gas used to be, which seems unlikely as I understand the proposals are to do it near the sources of cheap electric energy to avoid putting strain on the electricity grid, Hydrogen would need to be tranported over much longer distances and at higher pressures than the Hydrogen-containing town gas ever was.
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The Government's "Maritime 2050" and "Clean Marine Plan" documents make reference to hydrogen-powered vessels, including one that was being developed for use in car ferrys for the Scottish islands, using locally-generated hydrogen made by utilising surplus wind power electricity. The project seems to have had problems, as no purely hydrogen-powered vessels are currently in service.
https://transform.scot/2023/07/11/fossil-free-ferries-cpg-inquiry/
Norway has however recently introduced a Hydrogen-powered car ferry, said to be the world's first.
https://www.google.com/amp/s/theorkneynews.scot/2023/09/09/a-new-day-for-the-ferryman-oisf/amp/
But as other posters have said, practical considerations mean that hydrogen propulsion for a UK canal boat does seem to be a no-no.
I note that the linked Press Release in post #1 of this thread refers to
" To address this, the Clean Maritime Plan mandates new vessels to possess zero-emission capabilities starting in 2025. "
However, my understanding is that the Clean Maritime Plan (or at least the version I downloaded dated July 2019) merely sets out ambitions and specifically does not envisage mandating targets.
For example, page 6 paragraph 8:
"These zero emissions shipping targets are intended to provide aspirational goals for the sector, not mandatory targets. They can only be achieved through collaboration between government and industry, promoting the zero emission pathways that maximise the economic opportunities for the UK economy while also minimising costs for UK Shipping "
paragraph 10
"In order to reach this vision [ In 2050, zero emission ships are commonplace globally] by 2025 we expect that :
i. All vessels operating in UK waters are maximising the use of energy efficient options. All new vessels being ordered for use in UK waters are being designed with zero emission propulsion capability. Zero emission commercial vessels are in operation in UK waters. "
Perhaps some legislation has been, or will be, enacted to give legal force to these ambitions and aspirations, but I haven't seen or heard of any such legislation. In their absence, the 2025 date would appear to be merely one of the "zero emission shipping aspirational goals" of paragraph 8.
On the face of it, the document does not apply to canal boats anyway. Section 8 of the "Maritime 2050" document on which the Green Marine document is based, says it covers the following three sources of shipping:
* Domestic shipping - ships which have come from a UK port and are making a call at a different UK port.
*International shipping - ships calling at UK port (sic) which have come from or are going to an international destination.
* Shipping in transit - ships which are not calling at a UK port but which are passing through UK waters.
Canal boats do not normally travel between ports, so don't appear to be included
Of course, these documents have no statutory effect themselves, legally-enforceable provisions must be set out in Acts of Parliament and/or Statutory Instruments enacted by Parliament. I suspect that the Government have been occupied with other more pressing matters over the past few years to get round to shipping, but I am happy to be corrected.
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The coal gas that we had before the switch to natural gas in the 1970's, contained about 50% Hydrogen, but coal gas was distributed at a much lower pressure than natural gas, and generally in iron pipes, rather than the yellow plastic gas mains and relatively thin-walled copper piping used in houses today.
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Plus gas, (or petrol lighter fluid if you have no Plus Gas, or even motor spirit), can be effective on badly-rusted bolts, but you will also need patience.
The technique I have used with some success is to first apply some fluid and then work the head to and fro with a spanner. Steel is not infinitely rigid, and with luck you should see a ring of rusty fluid start to appear at the interface between the bolt and what the bolt is screwed into. Flush the rusty fluid away and repeat with clean fluid. The appearance of the rusty ring indicates that the thread adjacent the surface has released slightly, enough to allow some movement between the bolt and what it is screwed into.
Repeated to and fro moving of the spanner and flushing with clean solvent will pump out more and more rust, allowing more and more of the thread to be released as the fluid penetrates deeper and releases more of the thread. Applying too much torque too soon could shear off the bolt.
Conversely, if you don't see a ring of rusty solvent no matter how much you move the spanner to and fro, then the rust will have effectively welded the bolt in position, and cutting it free will be necessary.
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As the present resident of 10 Downing Street has just announced his desire to cut public spending to reduce taxes, I very much doubt that any significant additional cash for canals would be forthcoming.in the near future.
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Yes, definitely wasps. We did once have bees using the same air bricks to make a nest under the floor at the front door and I regretfully had to dispose of that too.
When I rewired our house shortly after moving in some 40 years ago, I found an abandoned wasps nest the size of a football attached to the joist with the old electric cables passing through it.
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I have found ant powder to be very effective in destroying wasps nests. Some years we see wasps coming and going through the air bricks by our front door, and an application of ant powder to the air bricks they are using so that the wasps have to walk over it, has always resulted in no more wasps the following day. My wife is allergic to insect stings so they really do have to be eliminated.
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A couple of decades ago, the school where my wife was then teaching, did a fundraising event for what was then a well-known national charity. Some of the sixth formers were concerned about how much some of their promotional goodies being given to the participants would have cost, and on investigating, apparently found that well over 90% of the funds raised by the charity went to administration costs. They never had any involvement with that charity again, and decided to only support those where most of the money raised was actually used for charitable purposes. My recollection is that subsequently, negative publicity about how little of that charity's income actually got used for charitable purposes, led to it changing its name and (hopefully) a change in its behaviour.
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26 minutes ago, matty40s said:
More likely a police aware sticker.
I remember seeing footage on a TV news programme a few years ago of a village in a narrow valley, I think in the West Country, where a heavy flash flood had ripped through it, entering some houses well above windowcill height, and leaving parked cars unusable. The programme showed footage, filmed by a resident while the road was still partially flooded, of a parking warden ticketting the previously-submerged and therefore undrivable, cars.
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They had bendy buses in Germany in the early 1960's.
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On 14/02/2023 at 21:23, Flyboy said:
I think you meant "Sailing". "Sailing By" is a Ronald Binge classic which some of our older members will remember as the theme music for the late night BBC shipping forecast.
A beautiful piece of of music that makes me picture a sailing tall ship. An excellent piece to play loudly through Harecastle or Standedge tunnels.
"Sailing By" is still played on Radio 4 just before 00.45 every night to introduce the shipping forecast. The music always finishes at the same time so that the forecast can always start at the same time, so if the "Book At Bedtime" which normally precedes it over-runs, the start of the music gets cut off. Not sure how much longer the shipping forecast will last as the BBC are closing their long wave transmitter in March, after which the alternative Radio 4 long wave programmes like "The Daily Service" and "Yesterday/ Today In Parliament" are migrating to the digital channel BBC Extra.
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A wooly jumper of course!
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Builders's merchants used to have racks of manufacturers' documentation, but I can't recall seeing any on compression fitting assembly. I tighten until I get what feels like the right resistance. I still have a very useful set of Osma leaflets I picked up more than 40 years ago, with fully dimensioned drawings of their soil and waste fittings and comprehensive installation instructions. Most of the fittings are still in production today.
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9 hours ago, MtB said:
More pertinently IIRC, the three classes were hardened to different degrees. From memory one was thick-wall soft copper i.e. hand-bendable, one was "half-hard" so was rigid but could be bent in a tube bender, and the last was "thin-wall hard" and would snap if you tried to bend it.
That's correct. When in the mid-1970's I replumbed my house and installed central heating, I specified the half-hard (medium wall thickness) stuff for the 15mm pipe as I needed to make slow bends in places to promote gravity circulation in the central heating circuit branches, thin wall non-bendable for the 22mm for the central heating distribution pipes and the 28mm gravity circuit to the hot water tank heat exchanger, because the thinwall was significantly cheaper than the bendable stuff and I was on a tight budget.
In fact the builders' merchant delivered medium thickness 22mm pipe and only charged me for the thin stuff, so I invested in a 22mm bending spring. I did manage to put some small, very large radius, bends in the 28mm thinwall stuff to avoid having dead horizontal pipe runs in the gravity circulation circuit by heating the pipe with a blowlamp and using a home-made bending block. It did cripple slighty in places but didn't crack.
The only time I have seen the fully annealed stuff being used was when the council replaced mum's incoming mains cold water pipe at around the same time. I guess nowadays plastic pipe would be used for that instead of the fully annealed copper stuff.
I never over-tighten compression fittings, but I do usually apply a smear of pipe jointing compound to the olive for extra security.
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When I replumbed my first house in the mid-1970's, copper pipe dimensions were specified by BS 2871. There were three classes, defined in its tables X, Y and Z .
For 10mm pipe, the wall thicknesses (in mm) were 0.6, 0.8, and 0.5 respectively (the tables were not named in order of wall thickness).
That BS was subsequently replaced by EN 1057, and this specifies the following wall thicknesses for 10mm pipe: 0.6, 0.7, 0.8, and 1.0 mm.
More info here:
https://www.engineeringtoolbox.com/en-1075-copper-tubes-d_2115.html
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The air seems to be in the form of thousands of tiny bubbles and I understand is designed to break up the boundary layer between the hull and the non-bubbled water, making it more slippery.
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Mr. Pedrick, ably assisted by his cat Ginger, who is usually remembered for his wacky inventions, did patent a method of reducing the drag of ships by blowing air out under the hull to provide a layer of bubbles between the hull and the water. Not such a wacky idea perhaps, as I once saw this patent cited as prior art in the search report of a patent for just this sort of thing filed by a German company. I do wonder if this technique is actually being used commercially, as the cruise ship we were on a decade ago seemed to have a strip of bubbles all along it between its hull and the sea, but possibly there is another explanation for the bubbles?
In a canal boat, even if it works, I would think that the energy required to pump the air would probably be greater than any energy saved by drag reduction.
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My understanding is that, because road tax is not hypothecated, motorists pay more in road tax than the government spends on roads, so motorists subsidise general taxation. Even if my understanding about road tax is not correct, I believe that it is certainly so if what motorists pay in fuel duty is included.
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3 hours ago, magnetman said:
The answer is to move away from insividual transport solutions in favour of mass transit.
That's a sensible philosophy in principle, but unfortunately successive governments seem to have been doing their best to make it difficult for people to use public transport. It's fine in the large cities such as London where politicians seem to congregate, less so elsewhere.
When I lived in East London in the 1950's and 60's, no-where was more than 10 mins walk from a bus stop, and most buses ran a frequent service all day from before 6AM to midnight. All my extended family in East London and the suburbs lived no more than a few minutes' walk from a local tube station, and no-one needed a car to get around. Trains used to run on bank holidays, even including Christmas Day, when the trains ran until about 2PM. We used to have christmas dinner at home and then catch a train to whichever relative was playing host that Christmas.
When I moved to outer London in 1970, we were a few minutes from a station on the Liverpool Street line. Trains used to run all night, and although I then had a car, it was more convenient for a night out in the West End with friends to go by train. There was no last train home, the service was just less frequent at night, the longest gap being about 2 hours between 2.00AM and 4.00AM, but there was plenty of seating at Liverpool Street and a number of vending machines for food and drink, even one selling ice cream and lollies. There was also a night bus to Victoria every 15 mins all through the night, which I did use to get to Victoria at around 4.00AM to catch a night train to Gatwick for an 8.00AM flight departure.
Unfortunately, in the run-up to privatisation, the government allowed (encouraged? instructed?) BR to cut back the less profitable all-night services to make them more financially attractive to potential franchisees. My last trains back home from Liverpool Street were cut back, firstly to 1.45AM, and later to its present 00.55AM, meaning that for a late night out I had to either take the car or else pay around £60 for a cab.
I understand that It's even worse in rural areas, especially where there is not even a regular daily bus service, let alone a night bus service..
So it's not really surprising that those who do not live in large cities, still need their own transport.
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I guess it depends on what the surface is like. If you have a smooth metalled surface, a two-wheeled sack barrow will be fine, but if the surface is unmade or rutted, a single wheeled barrow with a large pneumatic tyre may be more practical.
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The article does not make it clear what proportion of the heat pumps are air source and which are ground source, but all the specific examples given are ground source.
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Ole Øystein Haugen, a retired metalworker who lives just outside Oslo, convinced three of his neighbours to get ground-source heat pumps after he got one himself seven years ago.
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Likewise, the early Swiss and US examples quoted are ground source. Unless you are in a permafrost region, in the depths of winter, the ground temperature at moderate depth will always be above freezing and therefore warmer than the air above it, and in mountanous regions, the rocks will often be warmed by geothermal heat emanating from the earth's core or, in the case of granite, by natural radioactivity.
Climate can also be a factor. In the northern USA and Central Europe, especially in mountainous regions, the humidity in the depths of winter is often very low indeed, meaning that there is little water vapour in the air to form ice on the cold heat exchangers of air source heat pumps. Brits who are acclimatised to the damp climate of the UK will normally suffer from dry throats when taking skiing holidays in the mountain resorts of Austria or Italy, due to the lack of moisture in the air.
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A poster on this forum mentioned that a heat pump manufacturer's information was that a water temperature greater than 5°C was essential, which is greater than typical canal water temperatures established by measurements taken during winter cold snaps.
Heat pumps work by extracting heat from one environment and delivering it at a higher temperature to another environment. Your domestic fridge is a type of heat pump. If the environment (canal water) from which you are extracting heat is already at a temperature close to freezing, then the act of extracting heat from it will soon cause the water in contact with the surface of the "cold" heat exchanger to freeze, which will inhibit the pump's ability to extract further heat. The ice surrounding the "cold" heat exchanger will just get progressively colder, preventing the relatively warm canal water from which heat should be extracted, from coming into contact with the surface of the "cold" heat exchanger.
Heat pumps produce a certain temperature difference between their "hot" and "cold" heat exchangers, so the colder the "cold" heat exchanger becomes, so the temperature of the "hot" heat exchanger becomes correspondingly cooler. This is why air source heat pumps don't work effectively in really cold weather. I understand that air source heat pumps may need to periodically heat their exterior heat exchangers in frosty weather to melt any ice that builds up, in order for them to continue delivering heat to the "hot" heat exchanger. Otherwise the ice would become cooler than the air from which heat was supposed to be extracted.
No practical experience of heat pumps other than domestic refrigerators, but I did study their theory in the thermodynamics module of my engineering degree course many years ago, and I don't think that the laws of physics have changed in the mean time.
Vinly self adhesive tiles 1.1 sq m
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When I bought some genuine Formica more than 30 years ago, it was only available in sheets about 10' long by 4' wide. I only wanted it for a kitchen table I was making, so I had plenty left over!