Without trees?
Or modern trees, made of steel?
Shaping the future
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Hotrodder
- Posts: 3272
- Joined: Mon Jul 12, 2021 8:31 pm
- Location: Brittany 22
Shaping the future
Look on the bright side. No leaves to sweep up, and fewer broken branches to clear.
On my headstone it will say: Please switch off mobile phones. I'm trying to get some sleep.
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RobertArthur
- Posts: 2638
- Joined: Sat Jul 17, 2021 3:10 pm
- Location: Nièvre
Shaping the future
@ Hotrodder, thanks for cheering me up. I should have known better. Shaping the present. A compact mass of leaves, almost concrete, black mud in this gutter downpipe, forcing an entry point and then cleaning from several sides.
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tagh
- Posts: 657
- Joined: Sun Jul 25, 2021 1:21 pm
- Location: Pas de Calais.
Shaping the future
Once we have got the technology right hydrogen is the future; perhaps we should see the ‘windmills’ as a short term phase, say 10-20 years.
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exile
- Posts: 2648
- Joined: Mon Jul 12, 2021 9:57 pm
- Location: Auvergne Rhone Alpes
Shaping the future
And what technology would that be @tagh?
I have very serious doubts about H2 technology.
1. 95% commercial H2 comes from decarbonising methane and so produces CO2.
2. Water vapour is a more powerful greenhouse gas than CO2.
3. Electrolysis of water to produce H2 is fairly inefficient (which is why a different technology is used today) and needs electricity to produce it. So essentially you need electricity to produce H2 so that it can produce rather less electricity. Anyone else spot an efficiency issue?
4. Safety fears over hydrogen are rather overstated* but safe storage is still a major issue - especially if it is going to be in every car and motor bike.
* The Hindenburg disaster was largely caused by the doped fabric around the airship frame not the H2. H2 does burn in air and in the wrong conditions it can explode but its ability to float away means that it is relatively difficult to create the conditions for an explosion - although our Chemistry Master did manage it and destroyed the equipment used to produce the H2 in the process.
I have very serious doubts about H2 technology.
1. 95% commercial H2 comes from decarbonising methane and so produces CO2.
2. Water vapour is a more powerful greenhouse gas than CO2.
3. Electrolysis of water to produce H2 is fairly inefficient (which is why a different technology is used today) and needs electricity to produce it. So essentially you need electricity to produce H2 so that it can produce rather less electricity. Anyone else spot an efficiency issue?
4. Safety fears over hydrogen are rather overstated* but safe storage is still a major issue - especially if it is going to be in every car and motor bike.
* The Hindenburg disaster was largely caused by the doped fabric around the airship frame not the H2. H2 does burn in air and in the wrong conditions it can explode but its ability to float away means that it is relatively difficult to create the conditions for an explosion - although our Chemistry Master did manage it and destroyed the equipment used to produce the H2 in the process.