Should we ban kerolox rockets

[Aedile]

Personally I'm not a "BOO HOO, THE ENVIRONMENT, HUMANS ARE EVIL, WE SHOULD GO BACK TO CAVES" type person but I do feel we should do stuff to protect the environment, anyway kerolox rockets are probably the most CO2 intensive vehicles on the planet, with at least 2 launches per month and if SpaceX succeeds with their plans we could have up to 5-10 keralox rockets, maybe. Should they be banned, should all rockets be forced to use hydrolox?

Ha ha, you know the hydro in hydrolox comes from methane reformers, which produce CO2. So it's not that much cleaner as one might think.

[cicatrix]

Yeah, kerolox is bad Let's stick to UDMH/NTO (Much much healthier! ) )

Really, cows produce more CO₂ daily than all kerolox launches together since the beginning of space era.

[MBobrik]

Germany is an edge case. Most pollution is produced by China and US. EU follows with notable gap. Politics is a huge factor, but even with the right policy, we cannot switch everyone over in just a few years.

Germany shows us that a change of infrastructure is economically possible right now. Even though it demonstrated it by changing in exactly the opposite direction of what is needed.

There is no other reason than political that Germany converts its nukes to coal and not in the other direction, and there is no other reason than political that prevents other countries from changing their infrastructure too.

Sounds about right. Now consider that life time of a panel is about 20 years. So that is 3 years before it pays for itself.

Now consider that the same number applies to an oil shale field ( or mine ? ) too. But we are all putting our money there, and nobody is saying that it does not pay out.

[shynung]

Ha ha, you know the hydro in hydrolox comes from methane reformers, which produce CO2. So it's not that much cleaner as one might think.

That's black hydrogen. It does come from natural gas (methane), and contributes to CO2 production as well. If the hydrogen comes from water-cracking plants (electrolyzers), it's an energy storage medium. While locally CO2-free, it's quite energy-intensive, so the CO2 contribution depends on where the energy source ultimately came from.

[Aedile]

That's black hydrogen. It does come from natural gas (methane), and contributes to CO2 production as well. If the hydrogen comes from water-cracking plants (electrolyzers), it's an energy storage medium. While locally CO2-free, it's quite energy-intensive, so the CO2 contribution depends on where the energy source ultimately came from.

Current water splitters can store around 40% of the energy used. The problem of course is getting enough "green" energy to produce the hydrogen. If fossil energy is used, a reformer is actually cleaner than splitter.

On a side note, levelized cost of onshore wind (e.g including all costs including the power-plant), is around the same as gas. This is when it works at 30% of capacity.

Technology has progressed quite a lot in last decade, unlike political will and investment logic.

Edited December 22, 2014 by Aedile

[MBobrik]

Current water splitters can store around 40% of the energy used.

high temperature electrolysis got around 64 %.

[K^2]

Germany shows us that a change of infrastructure is economically possible right now.

I'm sorry, but did you just compare building a bunch of coal-burning boilers with the problem of mining, refining, and using uranium or another nuclear fuel safely? Germany basically had to weld some tanks and buy some coal. That's the extent of this particular infrastructure change. Don't get me wrong, its still massive on scale alone, but converting the other way, from coal to nuclear, is a whole another problem. There's a reason why steam power is early 19th century tech, and nuclear power is second half of the 20th.

Now consider that the same number applies to an oil shale field ( or mine ? ) too. But we are all putting our money there, and nobody is saying that it does not pay out.

Return from oil field is within months. Not decades. Completely different time scale. I'm not saying it's not economical. It's just that if you can have your profits later this year, or later this decade, most people go for former.

[MBobrik]

I'm sorry, but did you just compare building a bunch of coal-burning boilers with the problem of mining, refining, and using uranium or another nuclear fuel safely? Germany basically had to weld some tanks and buy some coal. That's the extent of this particular infrastructure change. Don't get me wrong, its still massive on scale alone, but converting the other way, from coal to nuclear, is a whole another problem. There's a reason why steam power is early 19th century tech, and nuclear power is second half of the 20th.

Well, the numbers tell a different story. Coal 2900 $ / kW installed, nuclear $5500 / kW installed. Which is surely bigger, but not that bigger as your description of tech level difference between "1800's coal burning boilers" and "hyperadvanced 1950's high tech" might suggest.

Return from oil field is within months. Not decades. Completely different time scale.

Seems unlikely because they got the same EROEI as solar panels. I don't think that oil fields are fast to set up and that short-lived.

[magnemoe]

Well, the numbers tell a different story. Coal 2900 $ / kW installed, nuclear $5500 / kW installed. Which is surely bigger, but not that bigger as your description of tech level difference between "1800's coal burning boilers" and "hyperadvanced 1950's high tech" might suggest.

Seems unlikely because they got the same EROEI as solar panels. I don't think that oil fields are fast to set up and that short-lived.

Construction time is far longer with an nuclear plant however the main problem is lawfare.

For oil it depend a lot on the location, deep offshore takes years to set up, simple wells is far faster and will give money back pretty fast.

[Rdivine]

I understand that changing the rocket fuel blend would not affect pollution very much. But, if you want to go that way, using LHLOX is much better. It is cleaner(its reaction produces water) and since water is generally a lighter compound, the specific impulse of the rocket is significantly increased. However, storing it would be tough.

[shynung]

I understand that changing the rocket fuel blend would not affect pollution very much. But, if you want to go that way, using LHLOX is much better. It is cleaner(its reaction produces water) and since water is generally a lighter compound, the specific impulse of the rocket is significantly increased. However, storing it would be tough.

Liquid hydrogen is a tough beast. If not kept below 20 K, it boils away through the tank's walls. And it blows up with the slightest spark if a large concentration managed to spawn itself. Not to mention that a hydrogen flame is almost invisible, one can walk into it and never realize that he's burning until the heat sets in.

[MBobrik]

Construction time is far longer with an nuclear plant however the main problem is lawfare.

This is exactly the point I was trying to make.

simple wells is far faster and will give money back pretty fast.

I was talking about oil shale extraction. Which is almost as far from a simple well as it gets.

[NERVAfan]

Well I'm no expert.

24 mio hectares is about the size of the entire United Kingdom and this is just for the electrical production. If you want the heat too, I certainly would coming from Denmark, it's about 7x times these numbers, using this method.

Yeah, that's tiny on a planetary scale.

It's in Spain, so somewhat more efficient than putting a plant in ie. the UK or Denmark.

I don't think solar is necessarily a good idea for cloudy high-latitude countries like the UK.

Pumping water uphill does seem like a better solution, but it is highly dependent on geography and can be dangerous, since dams can and do collapse. If the geography isn't there... It becomes a mega project by itself.

We're talking about converting the entire world energy infrastructure; no matter what you do, it'll pretty much be a megaproject.

Yeah, the water vapor is tiny compaired to what evaporates from the ocean, but it is replacing co2 production and there, supposedly, water vapor is a much more capable greenhouse gas. So a plant like this would be adding to global warming, but whether it's alot or nothing, is beyond me, at this very early hour.

I don't think water vapor is "a much more capable greenhouse gas" at least in the current situation. These things are situation dependent; when you have a tiny amount of a particular greenhouse gas, every little bit has a big effect. When you have tons, most of the radiation at those wavelengths is already absorbed, so adding a little bit more is insignificant. Adding 300 ppm CO2 would have a huge climate effect on Earth; it would be nothing on Venus.

Most of the Earth's greenhouse effect is due to water vapor, but there is way more water vapor than CO2 in the Earth's atmosphere.

I'm still interested in knowing the enviromental cost of producing that many photo voltaic panels on such a scale, deploying them and maintaning them indefinately. If anyone has any ideas...

I don't know - and I'm not really sure that anyone does. There is more than one kind of photovoltaic cell - which kind? Silicon? Ga-As? That probably matters a lot?

While I do think a project like this could be possible, it is a mega project and there are other difficulties. Supplying the entire world from one megaproject in ie. Sahara (or perhaps 2-5 places world wide)... Would be awesome, but think of the cooperation needed and the infrastructure and how many contries would be entirely dependent on the goodwill of other countries, because they could cut the cables at any point. Think about how we need to scale it up often, to accomodate the parts of the world that want to live like we do (and who can blame them for wanting to?).

Oh, I wasn't actually suggesting one giant megaproject. The comment about fitting in Nevada was just to illustrate that it's a tiny amount of land on a global scale, not that we should actually put all the world's power production in Nevada.

I actually don't think solar-only is a good idea... it doesn't work well for high latitude countries with very little sunlight in winter, and for very cloudy areas.

I personally would favor a combination of nuclear and solar, plus biofuels as a carbon-neutral fuel source to make up times when the solar isn't producing well and for applications where high density is important like aviation fuel.

Edited December 23, 2014 by NERVAfan
fixed quote, finished incomplete sentences, megaproject

[NERVAfan]

I'm sorry, but did you just compare building a bunch of coal-burning boilers with the problem of mining, refining, and using uranium or another nuclear fuel safely? Germany basically had to weld some tanks and buy some coal. That's the extent of this particular infrastructure change. Don't get me wrong, its still massive on scale alone, but converting the other way, from coal to nuclear, is a whole another problem. There's a reason why steam power is early 19th century tech, and nuclear power is second half of the 20th.

True... but it would be a lot easier if people didn't make the nuclear regulations quite so insane. Uranium itself is not THAT bad... it's toxic (like other heavy metals) and radioactive, sure, but there are many chemicals used regularly in industry that are vastly more dangerous (EDIT: and yet much less regulated).

(Fission products are vastly more radioactive, but they aren't involved in the mining or refining... though there are some decay products in uranium ore. IIRC it's not all that much, though.)

[shynung]

I'm wondering how did this discussion went from kerosene-LOX rockets to renewable energy.

IMO, we should continue to use kerosene rocket for safety reasons, and then switch to methane when the oil dries up; they're both safer to handle than liquid hydrogen, and can be stored at higher temperatures. Not that it's going to do so in the next few years, anyway.

That, and we should limit the hypergolics to exoatmospheric use only.

Edited December 23, 2014 by shynung

[Bill Phil]

Unless we could somehow produce green hypergolics. But that's a big if.

[shynung]

Unless we could somehow produce green hypergolics. But that's a big if.

The British used kerosene and hydrogen peroxide in their Black Arrow rocket, which according to the Wiki, is hypergolic when heated to high temperatures. My guess is that the Black Arrow had a catalyst somewhere in the combustion chamber, to decompose some of the peroxide to hot oxygen and superheated steam, the reaction of which is highly exothermic, in order to ignite the rest of the peroxide, if any, with the kerosene fuel. Both the kerosene and peroxide had nothing but hydrogen, carbon, and oxygen molecules in it, so if done correctly, we'd get a hypergolic rocket with an exhaust gas composition similar to kerosene/LOX rockets. It may not look like much, but it's definitely better than UDMH/N2O4 hypergols which throw off nitrogen oxides by the tons.

[jwenting]

we should ban people asking to ban stuff... hmm...

[78stonewobble]

Yeah, that's tiny on a planetary scale.

I don't think solar is necessarily a good idea for cloudy high-latitude countries like the UK.

We're talking about converting the entire world energy infrastructure; no matter what you do, it'll pretty much be a megaproject.

I don't think water vapor is "a much more capable greenhouse gas" at least in the current situation. These things are situation dependent; when you have a tiny amount of a particular greenhouse gas, every little bit has a big effect. When you have tons, most of the radiation at those wavelengths is already absorbed, so adding a little bit more is insignificant. Adding 300 ppm CO2 would have a huge climate effect on Earth; it would be nothing on Venus.

Most of the Earth's greenhouse effect is due to water vapor, but there is way more water vapor than CO2 in the Earth's atmosphere.

I don't know - and I'm not really sure that anyone does. There is more than one kind of photovoltaic cell - which kind? Silicon? Ga-As? That probably matters a lot?

Oh, I wasn't actually suggesting one giant megaproject. The comment about fitting in Nevada was just to illustrate that it's a tiny amount of land on a global scale, not that we should actually put all the world's power production in Nevada.

I actually don't think solar-only is a good idea... it doesn't work well for high latitude countries with very little sunlight in winter, and for very cloudy areas.

I personally would favor a combination of nuclear and solar, plus biofuels as a carbon-neutral fuel source to make up times when the solar isn't producing well and for applications where high density is important like aviation fuel.

Well, I do know it's tiny on a planetary scale, but just look at pricing estimates for building ie. a highspeed train between LA and SF. People don't wanna move easily and it's hard and expensive to appropriate it. It would need to be a big empty area.

In any case I tend to think nuclear is the most appropriate option in well developed industrial nations. It's us that can make that work as safely as possible and the energy density of nuclear fission makes any mining, refining, transport, handling and disposal less of a megaproject.

[lajoswinkler]

I understand that changing the rocket fuel blend would not affect pollution very much. But, if you want to go that way, using LHLOX is much better. It is cleaner(its reaction produces water) and since water is generally a lighter compound, the specific impulse of the rocket is significantly increased. However, storing it would be tough.

Hydrogen doesn't grow on trees, you know?

You need to invest energy to strap it from compound molecules. In a world where most of energy comes from fossil fuels it is best to use kerosene because that has the smallest carbon footprint per "oomph".

One day, when people become reasonable and most of base load energy is delivered by fission breeders, hydrogen will become a viable thing for massive energy storage use.