Quizzes & Puzzles3 mins ago
There Is No Way That This Is Achievable
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A ban on sales of petrol and diesel cars by 2032? It is absolutely ludicrous and no doubt the UK government will want to take the lead to show how green we are. The environmentalists wont be happy until they have destroyed the UK economy. Donald Trump was correct when he said the majority of them had a political agenda, most of them are anti capitalist fanatics and are using climate change issues for their own ends.
A ban on sales of petrol and diesel cars by 2032? It is absolutely ludicrous and no doubt the UK government will want to take the lead to show how green we are. The environmentalists wont be happy until they have destroyed the UK economy. Donald Trump was correct when he said the majority of them had a political agenda, most of them are anti capitalist fanatics and are using climate change issues for their own ends.
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dannyK "What as happened to the hydrogen driven car? It is much more environmentally friendly. " ah that old one! - wastes 95% of the energy used to propel. Catastrophically inefficient. How to we get hydrogen? Electrolysis! using electricity, 1/5th of the electricity used is wasted, if that electricity is generated from fossil fuels that has already paid 4/5ths of the penalty to generate electricity. Sadly hydrogen is plentiful but always attached to something else, that take energy to recover. Very inefficient.
TTT:
"Using fossil fuels to generate electricity wastes 80% of the energy that could be got by using the fuel directly."
Not true. An efficient power station will convert around 45% of the chemical energy into electricity. The electricity is used at close to 100% efficiency.
If you use fuel in a diesel engine, or petrol engine, you get roughly the same thermal efficiency, so the same amount goes to waste.
Thus, the ideal model is to extract energy from wind, tides or solar (or other renewable), in order to provide the things we currently derive from fossil fuels.
The argument that these batteries and solar cells will provide their own sources of pollution is valid. However, the alternative is that we all use much much, much less energy, both in our domestic lives and through the industrial chain.
I honestly do not think people in the modern Western world can do that, without being either priced out of the market, or forced to do so by legislation.
"Using fossil fuels to generate electricity wastes 80% of the energy that could be got by using the fuel directly."
Not true. An efficient power station will convert around 45% of the chemical energy into electricity. The electricity is used at close to 100% efficiency.
If you use fuel in a diesel engine, or petrol engine, you get roughly the same thermal efficiency, so the same amount goes to waste.
Thus, the ideal model is to extract energy from wind, tides or solar (or other renewable), in order to provide the things we currently derive from fossil fuels.
The argument that these batteries and solar cells will provide their own sources of pollution is valid. However, the alternative is that we all use much much, much less energy, both in our domestic lives and through the industrial chain.
I honestly do not think people in the modern Western world can do that, without being either priced out of the market, or forced to do so by legislation.
TTT
Isn't the internet extraordinary. One works on a subject, in depth for for years, and someone who clearly knows very little argues the toss.
You're right; China is building power stations, but they are also driving much faster than the UK toward electric vehicles. Many public service buses are electric; there are literally thousands of electric bikes on the streets of Shanghai and Beijing and Chengdu and other cities.
I know. I go there regularly.
And then, think about your philosophy of despair.
"I'll pollute all I like, because the big neighbour down the street is doing more of it. "
Every journey, as the Buddhists say, starts with a single step. Better to take that step and start the journey than sit on your backside waiting for everyone else to begin.
You can continue to sit there and moan and naysay if you want.
I choose to do what I can to make the world a slightly less bad place.
Isn't the internet extraordinary. One works on a subject, in depth for for years, and someone who clearly knows very little argues the toss.
You're right; China is building power stations, but they are also driving much faster than the UK toward electric vehicles. Many public service buses are electric; there are literally thousands of electric bikes on the streets of Shanghai and Beijing and Chengdu and other cities.
I know. I go there regularly.
And then, think about your philosophy of despair.
"I'll pollute all I like, because the big neighbour down the street is doing more of it. "
Every journey, as the Buddhists say, starts with a single step. Better to take that step and start the journey than sit on your backside waiting for everyone else to begin.
You can continue to sit there and moan and naysay if you want.
I choose to do what I can to make the world a slightly less bad place.
IJKLM, ok fair enough, I'm not anti electric cars etc I just think, to answer the original post, the 2032 target is pie in the sky and the cars themselves are not passing muster, I would not want to take a long trip in one. You may be an expert in this area but does that mean we all must simply nod and agree and worship at the feet of the "expert"? Better you alleviate our concerns than berate us for having the temerity to question conventional "wisdom".
TTT
I don't expect worship - how ridiculous you are.
Like many others, I find it irresponsible when people assert half-remembered half-truths as if they are accurate.
I can alleviate your concerns – and will, if you show that you are prepared to listen.
My experience of you on this site is that you hold certain views to be inalienable truths - even when they fly in the face of objective evidence.
So when you assert clear untruths in an area where I have worked for many years, I take the opportunity to call you out.
Nothing more than that.
I don't expect worship - how ridiculous you are.
Like many others, I find it irresponsible when people assert half-remembered half-truths as if they are accurate.
I can alleviate your concerns – and will, if you show that you are prepared to listen.
My experience of you on this site is that you hold certain views to be inalienable truths - even when they fly in the face of objective evidence.
So when you assert clear untruths in an area where I have worked for many years, I take the opportunity to call you out.
Nothing more than that.
IJKLM: "An efficient power station will convert around 45% of the chemical energy into electricity. The electricity is used at close to 100% efficiency. " - this: http://
claims about a a 3rd of the energy is made into electricity. It seesm both of us have the wrong figures, mine too low, your's too high. I will be quiting 2 3rds wasted from now on.
What's your view on hydrogen? do you agree that we have to use electricity(can't be sure it's not fossil fuel used to generate) to strip it from whatever it's attached to and as such makes it worse than a standard electrical vehicle?
claims about a a 3rd of the energy is made into electricity. It seesm both of us have the wrong figures, mine too low, your's too high. I will be quiting 2 3rds wasted from now on.
What's your view on hydrogen? do you agree that we have to use electricity(can't be sure it's not fossil fuel used to generate) to strip it from whatever it's attached to and as such makes it worse than a standard electrical vehicle?
Thank you
It seems I misjudged you. It's great that you are doing the research and finding good information.
I was wrong. And pleased to admit it. It means I learn something.
I was using the figure for a modern high-efficiency diesel engine, which is around 40%-45% (you can check that, if you like).
Petrol engines tend to run around 35% - 40% - at a similar level to power stations.
I'll admit I was guessing a bit that power stations operate at similar levels of efficiency to modern diesel engines, as they use basically the same heat cycle with intercoolers to squeeze a bit more energy out of the heat. Seems there is a preference to use the waste heat for industrial steam in a power station, and that brings the thermal efficiency of a power station down to the figures you mentioned.
It doesn't really take away from the argument that a grid powered wholly by fossil fuels collects the bad emissions in one location, rather than spreading it around urban environments, schools and so on (as petrol and diesel powered vehicles do). That centralised production also makes it easier to deal the emissions, should that become a priority.
Any contribution to the power grid by renewables reduces the overall emissions. As I understand it, renewables currently (2018) contribute around 29% of UK energy generation. Nuclear is 21%; gas is 40% and coal around 10%.
What do I think of hydrogen?
I think it is further away than battery storage, but probably will come, because batteries are themselves problematic.
Compressed hydrogen has an energy density of 142 MJ/kg. Lithium ion batteries have an energy density of 0.6 MJ/kg. Petrol, for comparison, is 46.4MJ/kg
That means there is more than twice as much energy in a kg of hydrogen, compared to a kg of petrol. And both are a couple of orders of magnitude more efficient at storing energy than lithium batteries.
There is a strong argument that the world will eventually move to a hydrogen economy, rather than an oil economy.
My crystal balls go a bit cloudy beyond 10-15 years so I can't predict anything beyond that period, and I'm pretty sure that the recovery, distribution and consumption of hydrogen is quite a lot further away than that.
One challenge, for example, is to ensure the hydrogen tank remains cold enough to contain the hydrogen in the event of a serious collision. Otherwise we're all driving around with (potential) bombs strapped to the back of the vehicle – though that's not so different from a tank-full of petrol, to be honest.
There are many others, not least – as you mentioned – the recovery of hydrogen from water. That needs energy. The same amount, or slightly more, than the oxidation of hydrogen delivers in a fuel cell.
As I noted earlier, a hydrogen-powered vehicle is an electric vehicle, just that the energy is stored in chemical form, rather than in batteries.
Hope that clarifies.
It seems I misjudged you. It's great that you are doing the research and finding good information.
I was wrong. And pleased to admit it. It means I learn something.
I was using the figure for a modern high-efficiency diesel engine, which is around 40%-45% (you can check that, if you like).
Petrol engines tend to run around 35% - 40% - at a similar level to power stations.
I'll admit I was guessing a bit that power stations operate at similar levels of efficiency to modern diesel engines, as they use basically the same heat cycle with intercoolers to squeeze a bit more energy out of the heat. Seems there is a preference to use the waste heat for industrial steam in a power station, and that brings the thermal efficiency of a power station down to the figures you mentioned.
It doesn't really take away from the argument that a grid powered wholly by fossil fuels collects the bad emissions in one location, rather than spreading it around urban environments, schools and so on (as petrol and diesel powered vehicles do). That centralised production also makes it easier to deal the emissions, should that become a priority.
Any contribution to the power grid by renewables reduces the overall emissions. As I understand it, renewables currently (2018) contribute around 29% of UK energy generation. Nuclear is 21%; gas is 40% and coal around 10%.
What do I think of hydrogen?
I think it is further away than battery storage, but probably will come, because batteries are themselves problematic.
Compressed hydrogen has an energy density of 142 MJ/kg. Lithium ion batteries have an energy density of 0.6 MJ/kg. Petrol, for comparison, is 46.4MJ/kg
That means there is more than twice as much energy in a kg of hydrogen, compared to a kg of petrol. And both are a couple of orders of magnitude more efficient at storing energy than lithium batteries.
There is a strong argument that the world will eventually move to a hydrogen economy, rather than an oil economy.
My crystal balls go a bit cloudy beyond 10-15 years so I can't predict anything beyond that period, and I'm pretty sure that the recovery, distribution and consumption of hydrogen is quite a lot further away than that.
One challenge, for example, is to ensure the hydrogen tank remains cold enough to contain the hydrogen in the event of a serious collision. Otherwise we're all driving around with (potential) bombs strapped to the back of the vehicle – though that's not so different from a tank-full of petrol, to be honest.
There are many others, not least – as you mentioned – the recovery of hydrogen from water. That needs energy. The same amount, or slightly more, than the oxidation of hydrogen delivers in a fuel cell.
As I noted earlier, a hydrogen-powered vehicle is an electric vehicle, just that the energy is stored in chemical form, rather than in batteries.
Hope that clarifies.
Oh, and combined cycle power stations in the UK run at around 45% efficiencies, so my guess was in fact pretty much correct - see fig 15 here.
http://
http://
TTT
I wonder if you read my 3rd-to-last para above:
"There are many others, not least – as you mentioned – the recovery of hydrogen from water. That needs energy. The same amount, or slightly more, than the oxidation of hydrogen delivers in a fuel cell. "
Like batteries, a hydrogen store is essentially a way of storing energy. That's the sustainability angle. There are a number of approaches to the production of hydrogen. One is to electrolyse water to create hydrogen and oxygen, another is to put methane (natural gas) through a plasma torch to split the carbon from the hydrogen (see for example, Monolith Materials).
The process is supposed to be sustainable, so the intention is not to find a pre-existing source of energy and then convert that to motion in a once-only conversion process (such as burning gasoline).
The aim is to find a process that uses one form of energy; converts it to a different form to generate the motion, and then recycle the proceeds of that process for future use.
Hoe that answers the question.
Retrocop: I think that was a report from about 6 months ago by a consulting company called Berylls
http://
It's true that using electricity generated by a 'dirty' process creates pollution. As noted above, the pollutino from a power plant is focussed in one place. That may be good or bad, depending on your perspective. Any contribution by renewables reduces the pollution burden, compared with a petrol or diesel-powered car, which is 100% fossil fuel.
Furthermore, if you look at a whole-life energy analysis (including making the batteries), even the Berylls report (which is quite pessimistic) indicates that an electric car turns the energy balance positive after three to five years.
I don't claim all the probems are solved. Far from it. That will take many decades.
What I do believe is that we are close to a turning point in the energy surces for the vehiles we use.
Hope it helps
I wonder if you read my 3rd-to-last para above:
"There are many others, not least – as you mentioned – the recovery of hydrogen from water. That needs energy. The same amount, or slightly more, than the oxidation of hydrogen delivers in a fuel cell. "
Like batteries, a hydrogen store is essentially a way of storing energy. That's the sustainability angle. There are a number of approaches to the production of hydrogen. One is to electrolyse water to create hydrogen and oxygen, another is to put methane (natural gas) through a plasma torch to split the carbon from the hydrogen (see for example, Monolith Materials).
The process is supposed to be sustainable, so the intention is not to find a pre-existing source of energy and then convert that to motion in a once-only conversion process (such as burning gasoline).
The aim is to find a process that uses one form of energy; converts it to a different form to generate the motion, and then recycle the proceeds of that process for future use.
Hoe that answers the question.
Retrocop: I think that was a report from about 6 months ago by a consulting company called Berylls
http://
It's true that using electricity generated by a 'dirty' process creates pollution. As noted above, the pollutino from a power plant is focussed in one place. That may be good or bad, depending on your perspective. Any contribution by renewables reduces the pollution burden, compared with a petrol or diesel-powered car, which is 100% fossil fuel.
Furthermore, if you look at a whole-life energy analysis (including making the batteries), even the Berylls report (which is quite pessimistic) indicates that an electric car turns the energy balance positive after three to five years.
I don't claim all the probems are solved. Far from it. That will take many decades.
What I do believe is that we are close to a turning point in the energy surces for the vehiles we use.
Hope it helps
Now is the time to get your grandchildren interested in cycling.......they'll be thankful in 20 years time.
In order for this legislation to work the government will HAVE to finally invest properly in proper, fit-for-purpose cycling infrastructure.
It's the only way to ensure better air quality and move a generation out of the sedentary, obesity epidemic that's no longer looming, it's right in front of us.
In order for this legislation to work the government will HAVE to finally invest properly in proper, fit-for-purpose cycling infrastructure.
It's the only way to ensure better air quality and move a generation out of the sedentary, obesity epidemic that's no longer looming, it's right in front of us.
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