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Ronaldo47

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  1. Going slower is not always going to be a commercially-acceptable option. When I was with GEC In the 1990's I once had dealings with Paxmans. Their then-new diesel was an attractive option for certain ferry operators in the Baltic whose ferry boats were then taking over 9 hours for a crossing. With the newer, more powerful engines, this could come down to under 8 hours, meaning that the services could be operated using only one 8 hour watch rather than two. Halving the labour cost more than compensated for the increased fuel consumption. I guess different economic conditions apply to modern mega-container shipping.
  2. The July 2020 isse of "Modern Railways" has an article that discusses the government's decarbonisation proposals for railways that confirms the government's intention to use spare electricity capacity for hydrogen production. Due to conversion losses a hydrogen train needs about 3.4kW of grid energy to deliver 1kW to the wheel, compared with 1.2kW for one powered directly from the grid, so only by using off-peak power would it be economically feasible, and these conversion losses would no doubt be the same for canal boats. Hydrogen also need seven times as large a storage tank as diesel for storing the same amount of energy, so for the same size of tank, a diesel tank's weeks would be a hydrogen tank's days. Re heat pump efficiency, my recollection from thermodynamics lectures at university is that a gain of about three is the theoretical practical maximum.
  3. Reminds me of the time when they dug up a few yards of one side of the road at a local shopping centre and put up the sign for "you have priority" on one side and "give way to oncoming vehicles" on the other side. Unfortunately the latter sign was erected upside-down, making both sides think they had priority!
  4. My understanding is that the speed for least resistance in a canal is when the boat speed equals the speed of propagation of a wave in rhe canal. At this speed you get a sort of resonance that minimises the energy required. I have tried this and it seems to work, often at speeds greater than 2mph, depending factors such as water depth.
  5. From #74 of the "Future of electric canal boats" thread. "My daughter is doing government paid research into hydrogen at Leeds university, she doesn't see it as a viable solution to cars, trains, or even lorries. I gave you some reasons why earlier their are plenty more. Ships and planes are better suited, ships especially as they can store it as ammonia where it's safe and stable."
  6. Update on Ford's electric problems: https://www.bloombergquint.com/business/ford-to-fall-short-of-europe-emission-rules-after-hybrid-recall Apparently the batteries in question are made by Samsung. I agree entirely with the previous poster. About 20 years ago we got the dreaded 2AM call from the hospital where my wife's mother had been admitted. She had suddenly taken a turn for the worst, and we had to drive to the other side of London for her last moments. My own mother was still living at home well into her 90's, but often had problems with falls and we could get calls at any time from her alerting service to go round and help her up.
  7. My understanding is that internal combustion engines have a speed at which they operate at their maximum efficiency. Range extender engines can be run at this speed and the improved efficiency could compensate for the energy lost in the conversion to electricity compared with an internal combustion engine providing direct mechanical drive and spending significant time running at a non-optimum speed. I recall that during the 3 day week era of the 1970's, when petrol was in short supply and lower speed limits were imposed, I consistently managed 56mpg from my Hillman Imp on runs between London and North Wales at 50mph. My usual consumption in built-up areas around town was 38mpg, and at 70mph on motorways, only 33mpg. Hydrogen no doubt has its place but, Hydrogen being considerably less dense than liquid hydrocarbons, requires a far greater volume to provide the same energy. I have been following the development of Hydrogen-powered trains in the pages of "Modern Railways". They have been trialled with some success in Germany, but the larger loading gauge usually found in Europe means that their trains have more space for under-floor fuel tanks and equipment. The one trialled in the UK needs a complete coach to accommodate its fuel and equipment, reducing passenger-carrying capacity. There is also the safety issue: the part of North Germany where trials gave been taking place is relatively flat and the absence of hills means that the lines normally have no tunnels. Hydrogen leaking in the open air would be able to disperse rapidly and be unlikely to result in an explosion, whereas it could build up in the confines of a tunnel. This is seen as a problem for the use of Hydrogen on the many UK railway lines that have tunnels, and the same consideration would apply to the narrow and often long tunnels found on the canal network. I well remember the spectacular explosion demonstrated in a school chemistry lesson that was produced by quite a small volume of Hydrogen gas.
  8. This reminds me of a book on plumbing I found in my local public library in the early 1970's shortly after the UK's conversion to metric, where they had simply converted all the imperial units to metric without applying common sense. It referred to a [nominal 40 gallon] cold water tank with an approximate capacity of 181.844 litres, and [psi] pressures of so many 453.7 grams per 6.45 square centimetres without also stating the orginal imperial units, although in the latter case they did retain the original imperial numbers. One of the worst [best?] examples I came across was the first metric catalogue produced by a US electronics company which, in its tables of design data, gave the metric value of Pi as 79.79. When I went on a camping holiday in North Wales for the first time, I wondered what the Llwybr Cyhoeddus was that all the public footpath signs were pointing to.
  9. The Far Tottering & Oyster Creek miniature railway designed by Rowland Emett for the 1951 Festival of Britain had what was supposed to be a spoof sign sayng "Persons throwing stones at this sign will be prosecuted" . Interesting to see it was not so far fetched after all! In the 1960's, the destination board on the buses of one of Carfiff's bus routes said ROATH DOCK SPLOTT. Spott is the name of an eastern suburb, short for Splottlands, originally Hospital Lands.
  10. When I had to replace the battery of my Vectra a decade ago, the manual warned that disconnecting the battery would mean having to reprogram the radio with a security code, this being an anti-theft feature. To save myself the trouble I connected a small 12V SLA battery to the battery cables with strong crocodile clips before removing the old battery and fitting the new one, and had no probems. As long as you turn off everything, such as lights and radio, first, the additional 12V battery does not need to have a large Ah capacity as it only needs to supply a small current to keep the electronics alive while the main battery is being changed. It is best not to attempt to charge a really flat battery with a fast, high current, charger. The high current density caused by current having to flow in the small conductive areas between the sulphated areas can lead to local heating of the battery plates. The consequential differential thermal expansion between the sulphated and non-suphated areas can force active material from the plates and lead to loss of capacity. Something similar to the French train problem happened to London Transport some decades ago. I think it was the Piccadilly line, where they ordered new trains with fewer, but longer, carriages to get new trains of the same length as the old ones but with greater capacity. They correctly calculated that the new trains would negotiate the curves in the tunnels, but forgot that tube tunnels bend up and down and well as from side to side: the longer carriages of the new trains fouled the tunnel roof at some of the sharper vertical bends, meaning that the track bed had to be dropped at those locations before the new trains could run.
  11. Re #145, it was aready there in Easter 2008, which was the last time we cruised the Southern Oxford. Unfortunately when we passed it I was steering, well wrapped up in warm clothes and thick gloves due to the very cold weather:- we had had several inches of snow fall the first night, more than enough to build a snowman on the gas cylinder cover in the bows as a combined figurehead and beer cooler. My camera was at the front, as were my teacher wife and student children, preparing lessons and studying for exams respectively in the warm, so I was unable to get a photo. Its chimney was smoking, indicating it was occupied.
  12. Is #132 somewhere on the Southern Oxford? It looks like what we saw there a decade or so ago. I did wonder at the time if it was a cunning way to get a habitable dwelling in the countryside without having to apply for planning permission or pay rates or mooring fees.
  13. I did read that the paperless road tax scheme was introduced to save money. What in fact happened in the years after its introduction was that licence revenue dropped by considerably more than the projected savings, resulting in a drop in income for HMG. I don't know what the present situation is.
  14. Can the public still buy traditional lead paints ? I know they are still made, but was under the impression that you needed to get a certificate authorisng its use. That was what I was told by a neighbour who is a manager of a local building firm that specialises in the upkeep of historic buildings. The stocks I laid in before its sale was banned are now almost exhausted. If you can get hold of any, I found that Calcium Plumbate primer was 100% effective. When we moved to our present house, the original 1930s Critall metal-framed windows of the bathroom and kitchen were very heavily corroded and deeply pitted in places. I removed all the glass and putty, used a rotary wire brush to remove the rust, gave two coats of the primer (it came in two colours to assist in getting complete coverage), and fnished with lead undercoat and top coat. That was more than 35 years ago and there has been absolutely no sign of the rust returning.
  15. "Bio" washing powder is best. I used to use it to de-coke the teapot we used at work.
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