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About agg221

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    Senior Member, Raffle Sponsor 2013, 2014, 2015
  • Birthday 03/12/1973

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    Milling timber, growing fruit trees, wooden canal boats
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  1. Yes, with some caveats. If you have a double-row of trees and one dies, it is surrounded on three sides. That means it is shaded, so will tend to grow towards the light rather than forming a balanced crown. If you remove a pair to create a gap, then re-plant a new pair of something else, they should stay relatively straight. If he wants a uniform looking avenue then the only option will be to have the trees all the same, which means for example removing every other pair and replanting, but if he wants it to look varied then you could look at removing the poorest specimens in pairs and re-planting with something else in the gaps, then once those are at a reasonable size, removing the rest and re-planting any large remaining gaps. If it's a decent sized estate, depending on soil and location, I would look at lime, beech or (only available as large specimen trees but if he has the budget and wants an instant impact) disease-resistant elm. Alec
  2. The Guy Martin programme was excellent in showing the pros and cons of current EV in an effective way, both at the vehicle and the systems level. It particularly highlighted the challenges of infrastructure. Just an observation (not a criticism), what it didn't do was to mechanically crush or pierce a cell. That would still induce a short which would set the whole pack off, even in a modern battery pack. That said, the risks are now relatively small. Any vehicle which carries its power on-board (unlike say a tram or an electric train) inherently carries a very energy-rich power supply and that means if it releases that energy faster than planned there will be fire/explosion. We accept this with hydrocarbon fuels so it isn't inherently worse than that, and is probably a lot better. Hydrogen does have a lot of potential. There are some technical challenges to solve still. The two big questions are on-board storage and the debate over how to use it. Petrol has the high energy density per litre because it's a liquid, but liquefied hydrogen isn't practical as the boil off rate doesn't really work in small volumes. That means pressure cylinders. To store more you can increase the pressure but that means they need to be stronger, so you either use thicker walls (=heavier) or more exotic materials such as titanium or wound single fibre composite (=expensive). An alternative is metal hydride storage but it remains to be seen exactly what the weight penalty is at systems level. It can be used to power an internal combustion engine as a near-direct replacement for petrol, or it can be put through a fuel cell. The former is very straightforward but it is not zero emissions as it still releases nitrous oxides. At the moment, the debate over zero emissions vs. zero carbon emissions has not been resolved. Fuel cells are much more energy efficient (nearly 3x the efficiency) but they use platinum as a catalyst and at 100g/car the entire global reserves are only about enough to convert one continent. Re-thinking transport as a whole makes sense. We have quietly made a lot of changes during the pandemic with the huge rise in internet shopping and working from home. Hauling the vehicle itself around is a much higher energy cost than the payload so home delivery in loaded vans uses less energy per item than the weekly shop or trips to B&Q and not doing the daily commute helps hugely. These do have to be traded against the societal impact and the effect on mental health though (although that does rather depend on who your colleagues are I suppose!) Alec
  3. The UK has 8 planned wind farms. Each wind farm needs how many sub-stations? 2 seems to be about right. That is demand for 16 sub-stations. Each sub-station should last the life of the project, judging by the life expectancy of existing sub-stations. I would say that a total requirement of 16 is pretty limited. Once built, that's it, the demand ends because the UK's supply is more expensive than other offerings in the international marketplace, so it does not have export potential. Other countries are ploughing in the money because they can build cost-effectively to supply an export market. This is because they are building on an existing infrastructure and have a lower labour cost base. The UK would have to invest in the infrastructure and would still have a higher cost base. It would also have to licence the IP. That means it would inherently be more expensive. Even if you believe the extra price is worth paying to serve the domestic market, and that the 'working class families' you believe this will benefit have plenty of spare cash to pay the associated increased costs of electricity that go with this, there is still not going to be any export potential so the whole infrastructure only lasts the lifetime of the UK build projects. That requirement is also over a short timeframe. That means you would build all the infrastructure and train all the people to meet a short-term requirement. The alternative would be to train far fewer people and build them over a much longer timeframe to artificially create continuous demand. The average working life is now supposed to be 50yrs. The current requirement is supposed to be met over 10yrs. If you drag out construction and hold up implementation, and only create 20% of the workforce then yes, I suppose you could argue it is continuous. If you geared up to deliver in the UK to the currently planned timeframe, what are all the people you have trained to do this going to do once their jobs are gone 10yrs later? If you create the very limited supply to delay implementation in order to artificially make the jobs sustainable, what are you going to switch off due to lack of electrical power to meet demand when you don't build it in time? I am quite open to alternatives, but only if they actually answer the key questions. So far you have not done this. You are quite right that we are not going to agree if you don't believe industries which underpin half a million jobs and contribute billions to the balance of trade are important, and you don't believe it is important to balance the books. I am no Thatcherite - even the GLC under Red Ken believed that was important! Alec
  4. I'm more directly familiar with the lighter end of electrical engineering - auxiliary gen-sets and similar, with Cummins and formerly Lister Petter. My father-in-law worked for both, my brother-in-law did his apprenticeship with Lister Petter and I have worked with Cummins. Certainly in that field the experience mirrored another area I have worked in directly - brazing. In both cases the skills were there when the development work was first being done, and when the infrastructure was being built in the 1970s, but the people with those skills are reaching the end of their careers and the residual knowledge in the workforce is diminishing. This is inherent in building something in limited volumes with a very long service life - by the time it needs replacing the people who went through the training to do it have retired, and in the meantime they end up either re-training or working overseas. This ties in with my earlier point about the challenges of sustaining a capability with only very limited demand - you either work very slowly to make the work continuous, or you end up with peaks and troughs. S&I is still around, sort of. It is now a division of Powell Inc. so it would depend on your perspective whether you regard that as British because it's where the jobs are, American because that is where the parent company is registered or global because it's a multi-national. If you approached them to build a sub-station of the type shown, I'm not sure whether it would get built in Bradford, or in one of their facilities somewhere else. I presume it would depend to a large extent on the costs, including the supply of components. Alec
  5. I see the picture, and if the UK had the skills and infrastructure in place to be the global supplier of substations I agree it would employ a lot of people to build it. The fact is that it doesn't, and investing in the whole underpinning infrastructure to develop the capability would not be cost-effective, particularly considering that it would only ever build a very small number to serve the very limited domestic market. I agree we are unlikely to agree. I would however suggest that your choice of words suggests that you have a preconception about certain industries - 'thousands of working class families' cf. 'just a few scientists' and I would challenge this. Taken from Wikipedia (but properly referenced and I have checked them): The pharmaceutical industry in the United Kingdom directly employs around 73,000 people and underpins over half a million jobs. One in five of the world's biggest-selling prescription drugs were developed in the UK. In 2007 the industry contributed £8.4 billion to the UK's GDP. In 2007 exports of pharmaceutical products from the UK totalled £14.6 billion, creating a trade surplus in pharmaceutical products of £4.3 billion. That's not just about a few PhDs - I would say that is a pretty big industry making a global impact and tipping the balance of trade a long way in the UK's favour? Alec
  6. I've always thought that Trabants were pretty cool, in a "so bad they're good" kinda way. There were loads still kicking around in Poland, eastern Germany and other eastern/central European countries the first time I went in the late 90s even. Somewhere around 2005 I was in Bucharest on business. The engineer at the company we were visiting picked us up from the hotel in his 1973 Dacia 1300. It was winter and the car was certainly memorable in many ways - lack of comfort being one of them. Most memorable was that driving in heavy traffic seemed reliant on faith rather than engineering - every time we went across an intersection, the driver would cross himself and go for it. I don't know if it worked, but we made it! Alec
  7. I'm not saying it's not worth changing. What I'm saying is that to implement change, you need a plan. We have a current system which has evolved rather than been created and it works in a holistic, self-consistent way. If you don't like it, you need to propose an alternative (unless the purpose is just to generally complain). The plan can't just cover one part - it needs to consider whether in making one thing better you make a whole load of other things worse with the net result that you are worse off. The plan has to be driven by need (supply and demand) rather than faith in human behaviour, otherwise at some point it will fall apart. Some questions which need to be answered: Where does the money come from to pay for the infrastructure you would have to build? Why are other countries going to give the UK the raw materials needed? If the UK is going to pay for them, on the international scale, what is it going to sell to generate the cash? What about the raw materials which other countries -won't- sell? I happen to be very familiar with the situation over indium for example, having worked specifically with first using it and then developing alternatives for nearly 20yrs and I can state with confidence that when other countries develop the capability, their approach is to add as much value as possible, rather than sell you the raw material. That's also what you are now seeing with wind turbine components. Ultimately, my opinion is that it is preferable to be the best at what the UK can do, and to trade this capability for the things which others can do better. The UK is world-leading in pharmaceuticals (the human genome was first sequenced here and that is being exploited), in structural integrity assessment and lifing of structures, in financial services, in some aspects of software and firmware (ARM, gaming, blockchain etc) and probably many other areas which I have overlooked. It has a plan to do the same for emerging net-zero technology. To me, it makes sense to invest in developing these capabilities further, rather than to invest in developing a second-rate capability to make something slower, poorer quality and more expensive than you could just buy from someone else, and at the same time make it harder to sell the things you are good at. I repeat the point, Soviet-style protectionism has been tried and it didn't work. What is the proposed alternative? Alec
  8. Who is this 'we' though? If you take it to its conclusion, you as an individual cannot trust anyone else and should be wholly self-reliant, at which point you should return to the stone-age and use only hand tools which you can make yourself. 'We' only really works if you consider humanity as a whole across the entire planet. If you work at any sub-level, and assume you want 21st century technology as part of that, everyone is inherently going to be dependent on everyone else. Take an example. Assume 'we' means Scotland, which cuts itself off North Korea style. At that point, some things it is going to not have anymore: Indium - so no flat panel displays = no smart phones, computers etc. Cobalt - so no high power batteries. Nickel and Chromium - so no stainless steel, no hard plating for hydraulics and valves, and coincidentally chainsaw barrels and other small two-stroke engines, no half-decent batteries and no advanced semiconductors. Gallium - so no solar panels (OK, less of a problem in Scotland!) but also even fewer semiconductors. Probably quite a few more, but these are the ones which immediately spring to mind. No unemployment problem though, as pretty much the only technology still available will be labour-intensive 19th century equipment so plenty of work for people as their productivity will be so low. Of course that isn't going to happen, but the point is that it won't happen because there will be trade. Trade will happen because the countries which have these things will want to produce a surplus which they will want to exchange for things which they need. You then have dependency again. It's not actually about trust, it's about mutual benefit, which is a much more powerful imperative. I do understand why it saddens you - the UK has spent the last 50 years changing direction and there are consequences. The simple answers are the Conservative party's ideology over decades of minimising state involvement leading to a policy of privatization, allowing anyone to gain control of a majority share in a publicly listed company, and the fact that the UK's nuclear development programme whilst technically superior in terms of performance was not as cost-effective and had some technical problems with the design (cracks in the graphite core) so was abandoned decades ago, so when the decision to build a new reactor was taken it hand to be bought from a company with a current design. Actually, it's only French operated in terms of the country in which the company was founded and is registered. The people on the ground will be employees of a French registered company, just as the current people on the ground building it are, but they are UK jobs, and the infrastructure which supports them creates more UK jobs. Most of the biggest companies are multinational anyway - unless they are state owned or controlled, the real owners could be anywhere on the planet. Is Amazon really a US company anymore, any more than BP is a British one? Actually, I disagree with the premise that heavy manufacturing being based in other countries condemns people to unemployment. That would only be true if there were no other options. They may not be the same jobs which people have been trained for, and I would quite agree the whole thing goes wrong if you simply take away the old jobs and do nothing to create new ones, but there are some good examples of how to go about this, along with the bad. The alternative is effectively a state-subsidised propping up of unproductive and inefficient industry. That was tried in the former Eastern Block and it didn't work very well. Personally I would rather not end up with a Trabant! Alec
  9. One area where I differ in thought from some of the other posters on this thread is the value of having 'home grown' capabilities purely for the sake of it. At the moment, we have free market capitalism as pretty much the global order. I see it rather like a scaled up version of an individual or a small business where you don't try to do everything but instead you focus on what you are good at, and in the process you earn money which you use to buy the things that someone else does better. You probably don't service your own vehicles and you definitely don't build them from scratch. You might buy in services in accountancy and legal expertise. Specific to tree work, you probably use a consultant when needed. The consultant can serve a larger base than just one arb company - their job exists to supply a bit of time to each of a wide customer base. In the same way on a global scale, some countries have resources and cost-bases which lend themselves to manufacturing steel; others to making precision parts; others to development of new products; others to provision of highly skilled services. So long as the UK has something to offer that the rest of the world wants to buy, in exchange it can buy in things which other parts of the world are better at. It is essentially still a barter system, using money as nothing more than an intermediary (which is why crypto-currencies work just as well, so long as they are trusted). Barriers to international trade for the sake of protectionism don't ever really work, unless like North Korea you are prepared to sacrifice the quality of life of your population. The UK has plenty to trade in exchange for equipment. To me it makes more sense to focus on what it is good at, rather than to invest in things that other countries can already do better and will always do cheaper. Alec
  10. I am also not entirely happy with the choice to use nuclear, mainly because we still don't have a proper long term storage option for the waste, but we are stuck with it for at least the next 50 years. Fusion would be preferable as the radioactive isotopes formed have very short half-lives but it is still a long way off. The next project, which has been a global effort, might just generate more energy than it takes to fire it up but it is still a research project rather than a power supply. Lithium ion batteries have three main components - an anode which 'stores' the lithium, a cathode which 'stores' the lithium compound and an electrolyte which allows the lithium ions to cross between the two. The electrolyte is usually an organic liquid (think diesel). During charging, the lithium metal deposits as individual atoms within the anode, which is usually made of graphite. If the battery is over-charged, you can get build-up of so many particles that they form solid metal. These regions form hot spots within the cells. Alternatively, if the battery is mechanically damaged, the anode and cathode can touch within a cell, forming a short circuit which gets hot. In either case, the heat in the cells can cause the cathode to break down, releasing oxygen. This burns with the organic electrolyte, generating more heat and forming gas. Eventually the cell container can burst, 'exploding' its contents and the heat causes adjacent cells to go up too, spreading throughout the battery until they have all burned. Because each individual cell contains both the fuel and the oxygen, they cannot be put out. Cooling does have some effect on slowing the spread. In the early days of battery development we punctured a cell with a laser whilst welding the connecting tab on - rather a blackened laser cell and our insurers asked what we were going to do differently if we wanted to continue to be insured... I entirely agree that if/how journeys are made needs a major review in the context of reducing energy consumption and that includes the school run. The reality for many in rural areas is that schools, place of work, shops etc. just aren't within a realistic travelling distance and public transport is not viable. That said, in more urban areas there are more options and walking/cycling to school should certainly be an option for many older children. I walked to my primary school with my mum, but she didn't work as in those days it was viable to pay the mortgage on a single wage. I didn't walk to my middle school (three tier system) as although the distance was OK, half a mile of it was up a main road with no footpath or verge. Secondary was 10miles and I only walked if I missed the school bus! My wife and I both work to pay the mortgage so both our children have been on the school bus since the age of 4. Fortunately my timings allow me to drop them at the bus stop. One indirect impact of COVID has been more people working from home and that looks likely to continue in part through hybrid or flexible working. Some jobs require you to be on site, but a lot of office-based jobs have more options. It's pretty bad for mental health to do that full-time though, and trying to develop functional teams is particularly challenging, so travel is going to have to increase again I think. Alec
  11. Unlikely to be fossil fuels. The main intention is nuclear (still fission, not fusion). Hinkley Point is well underway and Sizewell C will follow straight on behind (the team will move from one to the other as stages are completed). The big programme is the development of the Small Modular Reactor (SMR) with the intention of large scale international sales as well. I'm also not wholly convinced by electric cars, due to issues with the batteries (not so much the lithium, which can be obtained from seawater but more the issues with cobalt). For batteries to be practical, higher energy densities are needed than lithium is capable of. There are other chemistries which work in the lab but converting them to practical products is a different thing entirely, mainly due to the issue of managing these extremely energy-intense systems without them catching fire. Even the lithium ones burn rather well and can't be put out once started (we had a rather impressive fire whilst doing the development work on the assembly process for a major OEM). Travel to schools isn't that straightforward. My younger daughter is at primary - 3.5miles each way to the nearest one. Elder daughter is at secondary - 5.5miles to the one she attends, although there is a sink school about 3miles away if you just went for distance. If it was a mile or so it would be different. Alec
  12. I wasn't sure whether to dip a toe in this thread or not, but obviously I have decided I will. It's a nice idea to say that wind turbines should be built in the UK, but if you take that statement apart rationally, it's not obvious where you would draw the lines. Breaking down the turbines into their major units - foundations (jackets, legs etc), towers, blades and hub/gearbox you have different materials and processing requirements. Start with the simple ones - foundations and towers. How far down the supply chain do you want to go? We don't really have any high grade iron ore remaining, so that means either refining scrap or importing ore. We would then need to build a plant to do that, and in the current circumstances that would have an enormous level of emissions controls. Once you could make the steel, you would need a mill capable of rolling the right sections. Fabrication is going to be largely automated, as is the inspection, so a lot of capital investment but not that many jobs. Once you have built all of these facilities, given that it is running in a high labour cost environment and there is other, cheaper, global supply, it is only going to serve the domestic market, so the utilisation is going to be pretty poor. That means with high capital investment, high running costs and poor utilisation it will add astronomically to the cost of the steel components. Blades can be (and already are) made cost-effectively in the UK (see Vestas on the IoW). The hub and gearbox are large machined parts. If somebody wants to develop a new one from scratch which lies outside the intellectual property protection of the people who have invested in this so far, great, but it will probably take a decade of development before it can be launched. The alternative would be to use an old design where the IP has expired and accept the reduced reliability and efficiency. The capability to make these is still just about there in the UK with suitable capital investment, but I note that Sheffield Forgemasters has just had to be bought out by the government to save it from collapse, so clearly it isn't a very economically attractive proposition. So, once we have had the huge government investment programme, the timeframe to procure, install, commission and optimise, the UK should be able to produce massively expensive wind turbine parts for domestic use. The additional cost will of course have to be passed on to the consumer. It's hard to predict exactly how much it would add but something around 50% is probably about right to recover the investment in a reasonable timeframe. Increasing electricity costs by 50% in parallel with the net-zero decarbonising agenda may not be ideal? It would probably snarl up the economy quite well if people could no longer afford to travel to work in their electric cars, the price of delivery went up so all goods became more expensive etc. Of course, that could be overcome by increasing wages, but then you have an inflationary spiral. Fundamentally, what the UK is good at is selling services. It is also good at inventing things. Developing new innovative technology and selling it internationally as a service is the government plan around net-zero, and it at least has a ring of credibility about it. I could go on at great length about mis-placed investment and social engineering experiments are hugely reducing the effectiveness of that plan, but I won't. Alec
  13. It would be akin to extending the date stamp requirement on food so that anyone who sells a few apples or eggs from the gate has to provide a date stamp on them, and has to pay for the privilege of applying that stamp at such a high figure that they are forced to stop doing it, thereby giving the supermarkets a monopoly. Alec
  14. I would talk to Strippers of Sudbury and take their advice. And yes, they do supply the right sort of strippers! Some of what they can supply just needs application, wait, pressure-wash and does an excellent job. Much quicker than you might think as it goes on with a big wallpaper paste type brush. Alec
  15. Well it would certainly be energetic enough to count as a sport!


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