Obelix Posted October 19, 2012 Share Posted October 19, 2012 Well, I didn't feel like I was the one who started anything. But if that's your opinion then so be it. It's your superior attitude that grates with me I'm afraid....Like your post #101...who did you think was actually going to understand that? Evan Cavegirl asked you to speak in laymans terms. At the very least in this thread I'd have expected Cyclone, truman, T42 and metalman to have understood it. Link to comment Share on other sites More sharing options...
truman Posted October 19, 2012 Share Posted October 19, 2012 At the very least in this thread I'd have expected Cyclone, truman, T42 and metalman to have understood it. See post #120 I was editing as you were sending your post Link to comment Share on other sites More sharing options...
Obelix Posted October 19, 2012 Share Posted October 19, 2012 so energy in petrol produced is 10,000*1400 = 1.4 MWh about 1.9% efficient.. Something's not right..probably my maths.. 10kWh in a litre of fuel * 1400 litres is 14MWh not 1.4MWh... I think this is the problem? Link to comment Share on other sites More sharing options...
truman Posted October 19, 2012 Share Posted October 19, 2012 10kWh in a litre of fuel * 1400 litres is 14MWh not 1.4MWh... I think this is the problem? Yep..sorry decimal place slip ...still not a very good return is it? Link to comment Share on other sites More sharing options...
Cyclone Posted October 19, 2012 Share Posted October 19, 2012 20% isn't entirely terrible. But it's not awesome. Link to comment Share on other sites More sharing options...
caparo Posted October 19, 2012 Share Posted October 19, 2012 They make hydrogen by splitting water into its elements by electrolysis . But when you burn hydrogen and oxygen you get water back and far less energy than it took to split the water in the first place. The same applies to reversing the burning of hydrocarbon fuel. You can make fuel but it requires many times more energy than the fuel will produce when burned. That is just basic chemistry. So whilst the process is possible it is also totally pointless unless you have free electricity to start with. Even then that electricity would be better utilized powering the grid or railways. But it allows folks to waste a day discussing something that has no relevance to our energy needs. Link to comment Share on other sites More sharing options...
retep Posted October 19, 2012 Share Posted October 19, 2012 You need the turbines to produce the electricity to produce the "petrol from air" ....I'm not sure what you're saying..could you clarify it for me ..having a senior moment here Instead of the turbines standing idle as they do when the grid can't cope, you would be making petrol, batteries can't store all the extra power, so the petrol making is a by product and a extra fuel storage. Link to comment Share on other sites More sharing options...
anywebsite Posted October 19, 2012 Share Posted October 19, 2012 And quite rightly so, because schemes like this, and the Fischer Tropsch et al need an energy input. You can't just make it from air - you have to add in a considerable amount of energy from a power station. I'm sure I saw some Americans did it a few years ago using a parabolic mirror to concentrate solar energy. It wasn't on a commercial scale & that method would never work here for obvious reasons. Link to comment Share on other sites More sharing options...
anywebsite Posted October 19, 2012 Share Posted October 19, 2012 They make hydrogen by splitting water into its elements by electrolysis . But when you burn hydrogen and oxygen you get water back and far less energy than it took to split the water in the first place. The same applies to reversing the burning of hydrocarbon fuel. You can make fuel but it requires many times more energy than the fuel will produce when burned. That is just basic chemistry. So whilst the process is possible it is also totally pointless unless you have free electricity to start with. Even then that electricity would be better utilized powering the grid or railways. But it allows folks to waste a day discussing something that has no relevance to our energy needs. Have you looked at the efficiency of batteries? Their charging times? Weight/capacity? There aren't any efficient options if you want an electric car. It's hard to make an electric car, so the energy is better converted to a chemical form, like hydrogen or hydrocarbons to make it easier to store & transport. Trains can't replace cars. You can't easily run cars on the power grid. It doesn't require free electricity, just that the electricity to make synthetic petrol costs less than the petrol it makes. Link to comment Share on other sites More sharing options...
Phanerothyme Posted October 19, 2012 Share Posted October 19, 2012 If we could store energy as compactly as possible, at the efficiency of or greater than pump storage systems or modern flywheels, we could make do with much, much less of our generating capacity for all our domestic, industrial and transport needs. Energy doesn't take up much space after all. I envisage something the size of a housebrick with a couple of bus bars sticking out that could power a 3 bedroom house for a year before requiring a recharge. Heinlein called them "Shipstones" after their inventor, a Mr Shipstone, who if memory serves never patented them so he could keep their workings a secret. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.