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Was: Moss/Lichen on roof, now we are into pollution.
Jaques d'Alltrades wrote:
The message from The Natural Philosopher contains these words: Bob Hobden wrote: Fact is... All the major manufacturers and significant others are working flat out on Fuel Cell engines which produce no pollution except steam. Wrong. The hydrogen has to be made. An innefficent process that burns as much, if not more, fossil fuel than any other form of transport. Better to use batteries, and then whilst the electricity generation is still an issue, as with hydrogen, at least there is no need to build a huge new infrasturcture of hydrogen supply and handling equipment. And just how do you think electricity to charge the batteries is produced? With a loss approaching 30% at every stage: thermal value of fuel for power station to power delivered at charger (taking in power loss in transmission lines), charging the accumulator, discharging the accumulator all taken into account, the net result is a great deal more pollution to propel your so-called clean electric vehicle. Well first of all, because it isn't 30% at every stage. Thermal efficiency of a modern power station is up to 65% - more if you can use the waste heat to e.g. heat water for the neighborhood. Elecricity generators and motors can achieve over 90%, and transformers etc are typically around the 95% plus mark. I am not sure on distribution losses. Theortecically those can be as low as you like, by use of fatter or supercinducting cables. My extensive experience of charge/dishcarge of secondary cells suggests that 90% convesrion or better ins not uncommon. The big things in favour of all electric cars tho are (i) the initial electricity generation can be done by many different things - from windmills to nuclear power stations, as well as burning non fossil fuels (biomass) (ii) its a lot easier to scrub atmospheric pollutants from a power station flue than from a car exhaust. That doesn';t affect the hydrigen versus electric car argment tho. (iii) we already have an electrical distribution system that has huge off peak energy availability. And that is precsiely when we would be charging our cars up. Essentally tow electrckettles overnight is all it takes power wise, to get a full days motoring (unless you intend to drive to scoitland, in which case the electric car uis stll not able to cut teh mustard, although it is feasible to fully rechage current cells in about one hour at e.g. a specially equipped 'service station' Unless, of course, *YOU* can differentiate between the reciprocating electrons which are being excited by wind or hydro power........ Hydrogen would use electricity in greater quantities, needs an infrastructire to distribute and store it, It simpkly isn't there as a road fuel. Fuel cells are possibly better, but they don't seem to work yet and they have top produce some end producs that need disposal. And they stll use fossil fuel. OR very expemsive synthetic fuel. A car that will do 300 miles between an overnigh charge of 9-10 hours at 20 Amps is technically feaisble and hads been demonstrated. Got about 600bhp as well, and under 1.5 tons weight. And? Its here, it works. It needs nothing extra to be used immediately. It simply shifts teh burden of energy back to teh power stations, where it can actually be dealt with in a planned way, according to whatever policy you have in mind. Its just horrendously expensive on batteries right now. However the technology is advancing at huge rates, it has been done, it can be done, and I actually costed out how much it would cost ME to do it. Under £100,000 using multiple cell phone type batteries. If trhat cannoty be knocked down ny a gfactor of 5 I would be very surprised... Meanwhile they continue to develop even cleaner reciprocating engines. The Hydrogen to run Fuel Cells can be produced using sunlight eventually, to split water, so then we will be using the energy current account and not even extra heat will be produced above that the sun provides. I doubt that it can in any real quantity. The energy per unit area falling on teh earh is probably best used to make e.g. biomass, which is about teh most efficient process we have available. Much more efficient to burn the hydrogen in a reciprocating (or rotary) engine than to convert it through a fuel cell to run an electric motor, though electrically propelled vehicles do have the potential to convert the slowing down process back into usable power. Yes, but generating the hydrogen is inefficient in the first place, as is the means of delivering it. How much desle does it take to deliver each liter ifdiesel to your pump/ How much ti drive there and collect it? Its cheaper to deliver electricty than almost anything else. However the real simple answer that dare not speak its name, is 'why the **** do we need to go anywhere at all' and the answer is, mostly we don't. Lets face it most of what we do could be done in front of a console from home, if we had to. And I suppose the goods we need will be delivered through the telephone wires too? When I go shopping I visit a number of outlets. I can see what I want to buy, and reject what had interested me from its description. I generally share a car with a friend's family anyway, doubling the efficiency of a trip. Well, since he has a family, more than doubling it. Well, I don't. Apart from fresh food, and touchy-feely items, 90% of what i buy is done on the net now. I make my living off it now. Days go by when I don't even get into the car. The economies of scale really work with delivery driving. One van, going from depot to door, can carry as much as 15 cars going to te shops and back. One worker, sitting at a PC, not only saves (in our case) about 3500 quid a year in transport charges, but 4 hours a day commute time, not to mention all the hours sitting in the bog, chatting near the coffee machine etc etc. We reckoned that 20% more productivity at 65% of the cost was the difference between home working and going to work. Sorry, your dream will never catch on. It has. In my case, and in millions of others. E-shopping and home working is steadily becoming not 'unsual' but 'minority normal' Give it 5 years..and some tax breaks to encourage it... |
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