Indeed they are solar sails and would perform much of their maneuvering via that mechanism vs. active thrusters. The remaining capability would be via cheap electric thrusters. Some fraction of the area would be for solar panels, not just reflective mylar.
I think it is worth some research dollars, because assuming we make it through the current crisis with anything resembling a technological civilization, we’ll want active climate management.
I would take the current heat wave as an opportunity to recalibrate your expectations for your standard of living. It will get way worse in even the most optimistic scenarios. It’s going to be very interesting when hundreds of millions of people are displaced and some of them show up on your borders.
Indeed, interesting it is going to be. It is already, come to think of it. There are people talking of needing active climate management, go figure. As if that was feasible without unintended side effects. So interesting, this is.
But still, no hard feelings: it’s not your fault, neither it is mine. Your chain of thought is interesting too. I like it, I just don’t believe it.
Doubing the mass again? And trebbling quadrupling the price?
In addition, if you could make the propellant from directly-sequestered carbon, then the launches themselves would have a net-negative effect on emissions since they will be hauling some of the carbon into outer space.
Positing such an enormous increase in the availability of carbon-neutral energy that you can use it to make rocket fuel is not less implausible than positing the sun shields themselves, so I think they come for free in the hypothetical. Even under this rosy scenario, we’d still have all that carbon in the air for decades to come so we might still need a sun shield.
Of course there will be side effects. But long-term, we have no choice. Just think, the shields double as mirrors. So they can act to increase irradiance in case an asteroid or megavolcano causes some global dimming.
I think people sometimes get the wrong idea about various proposals. They should be weighed against the cost of doing nothing, which is a number in the hundreds of trillions of dollars, and possibly over a quadrillion dollars. Today, we’re doing only slightly more than nothing.
If a proposal mitigates 1% of the impact and costs <$1T, it’s probably a good idea. If anyone tries to dismiss a 1% mitigation as inconsequential, they’re probably not thinking very clearly about things. We’re going to need a lot of these mitigations, and they will be very expensive, but it’s too late for not expensive.
A lot of these discussions make me think of a homeowner with a $500k house being told that they need a $50k roof replacement or their house will be destroyed. Except the homeowner hasn’t heard the $50k number; what they heard is that the contractor said the first thing would be to apply some plastic sheeting as a patch, which will cost about $500… and the homeowner immediately goes into a tirade about how they can’t afford $500, and they’ll have to postpone their Disneyland trip next week, and how all of this is really an unacceptable inconvenience, and how dare the contractor even suggest such an inflated price, and blah blah blah…
Yeah. One nice thing about making rocket fuel–as well as other industrial chemicals like hydrogen and fresh water–is that you don’t need to store the electricity. Chemical storage is cheap; just a tank (or lake, in the case of water). Way cheaper than the cost of batteries. So you just run the plant when the sun is shining or the wind is blowing, and use tanks to buffer the fluctuating output.
A question I have about sequestration, is it better to spend the energy on sequestering carbon, or offsetting burning of fossil fuels?
If someplace out in the dessert I build a solar/wind farm and sequestration plant, using the best technology available. Then I only run the plant when the sun is shining or the wind blowing. Am I better on a carbon perspective using all of that energy to suck up carbon, or better just feeding it into the grid and offsetting the burning of fossil fuels.
Obviously that will depend on what and how much fossil fuels are being burned. My concern is that it is a fools game, like lots of biofuels.
What we’re experiencing is the new normal. There is a good chance that any given year might not only be the hottest on record, but also the coldest of the next 20.
It depends a lot on the details. For instance, suppose you overbuild solar production so it can handle early-evening A/C needs. That means you’ll have an excess at peak solar times (i.e., noon). What to do with that excess? If the capital costs to your sequesteration plant are cheap enough, you could use it there, but it would have to be very cheap if it’s only running a few hours a day. Of course, there are all kinds of other options, like smelting aluminum, or heating salt/sand for later thermal use, or desalinating water, etc. The right answer depends on the cheapest method of using that spare energy effectively.
I do have a hard time believing that direct air capture could ever be truly cost effective compared to the alternatives, but I’m willing to be proven wrong.
Another sequestration suggestion - back during the Vietnam war, tehre was one of those wacky out-there proposals I heard about to launch huge solar sails that would reflect sunlight onto Vietnam at night to help illuminate the nighttime movements of the Viet Cong. Apparently the idea was abandoned when it was determined that even low levels of sunlight for extra hours might cause the jungle to grow faster and thicker, making the job of finding the enemy worse.
So there you go - point solar sails at areas where the reforestation has happened to speed growth, if that will balance the extra solar energy provided. Or, illuminate solar power farms at night in the desert…
Here’s a concept for extracting CO2 from seawater and converting it to a hydrocarbon fuel (methanol) using solar power. From a peer-reviewed journal so hopefully not completely woo:
My Idea ⟨™⟩ is to harvest pine and other timber plantations, turn the wood into charcoal, and throw it down abandoned coal mines. Plant more trees there, rinse and repeat.
Charcoal is practically pure carbon and will obviously be safely stored where coal has sat undisturbed for millions of years.
How that works out in terms of energy budget I leave as an exercise to the reader!
Why do all that. Get a head start on peat bog creation by filling a finished open pit mine with dead trees. Filling a maze of tunnels (and maintaining those tunnels until you’re done) is expensive and not very voluminous. Without regular maintenance the ceilings start to spall and the tunnels become dangerous. Doubly so for coal mines. The ore mined in veins in mines is replaced by sand (ground up rock waste) as they go, for ground stability - so there’s not a lot of empty space to fill. Open pits are usually huge and easy to fill. (or fill natural valleys, too) The trick, I suppose, is avoid situations that lead to spontaneous combustion through biochemical processes that cause heat buildup. (Like how fermentation causes haystacks to catch fire)
I’m imagining that thanks to global warming, there’s probably an opportunity for humans to give the northern movement of the tree line a helping hand.
the problem as always is still volume. The amount we can sequester or capture with extra plant growth is probably not even close to what we burn every year to maintain our lifestyles. It will require a MASSIVE effort to make a dent.
So, turn hydrocarbons into charcoal and … CO2, CH4, etc? Charcoal pyrolysis isn’t greenhouse-gas emission-free, even if it was all done with the most modern recirculating retort methods, which it mostly isn’t.
Stranger - Have great respect for your knowledge and opinions. That video is one opinion, and a partially valid criticism of CCUS but it ignores a lot.
I have worked on renewable technologies including CCUS for the last 20 years or so. There are no existing pure Carbon Capture and Storage (Sequesteration) projects in operation because there was no incentive to store carbon until the last few years, in the US. Why would a power company or utilities company make their product twice as costly, if there is no one willing to pay for it ?
Having said that, CO2 has been captured (and agreed it is not at a scale to make a difference to Climate Change) and pumped underground for EOR (Enhnaced Oil Recovery) for decades now. Dakota Gasification, Petranova Thomson, TX, Air-Products/Valero at Port Arthur, TX etc etc.
So, there is a lot of success stories - that video conveniently dismisses.
Gorgon was first of its kind for Carbon Capture - and its failure causes are now understood and will help us design the next ones better.
Here is an interactive map of all the Carbon Capture projects going on - In the US and Worldwide (It includes Hydrogen projects too). Happy to say that there is a lot of investment going on
Old-growth forests do not sequester carbon. They have already sequestered carbon. In the past, while they were growing from young growth into old growth. Now, they’ve stopped.
It’ll depend on, on one hand, the inefficiencies in getting the power to where it’s used, and on the other hand, the inefficiencies in the fossil-fuel power plants and in the sequestration process. And the inefficiencies in getting the power to where it’s used will depend on how far away your desert is from populated places. But even across thousands of miles, there’s really not all that much inefficiency in power transmission, especially not if you spring for a bit of extra infrastructure on each end (converting to, say, extreme high voltage DC), so offsetting is almost certainly going to be the winner.
At least, in the first order, if the power really is offsetting fossil-fuel power. It’d really suck if people respond by using all of the fossil-fuel power and all of the new, green power. Which, people being people being people, they’re likely to do.
Lots of problem with this kind of idea. Lets start with some :
Freshly harvested wood is about 60% water. Transporting such wood for processing has a large carbon footprint.
Lumber companies and companies that make products like OSB (used in roofs, etc) - harvest a pine tree, keep the main trunk and have off all the branches. Its not economical to transport the branches and the branches are left to rot - returning the carbon to air.
Drying wood means removing that 60% water - which requires more fossil fuels
Making charcoal mean pyrolyzing wood - this releases Methane, benzene, tars etc, tha have several times the greenhouse warming potential than CO2.
And once again, such a project becomes almost trivial if we have managed to learn to use the resources that are already in space.
I’m also in agreement that this wouldn’t have nearly the negative effects on plant life claimed by others upthread. Even a 1% decrease in solar insolation would go a long way to decreasing the global temperature, and a 1% decrease is not going to have much effect on plant growth. If we get a bit fancy with it, and instead of just mirrors, we use filters, and filter out infrared wavelengths, then this can have an even greater effect on global temperatures while not bothering plants at all.
Agreed. We already have an effect on climate, we have completely changed the land use of nearly every square mile of land, and we aren’t likely to stop. If we are inevitably going to change the climate and ecology anyway, we may as well do so responsibly and with intent, rather than our current irresponsible methods with uncertain effects.
From a global warming perspective, you are better off feeding that power into the grid. That way you will avoid a lot more CO2 getting into the atmosphere - versus removing CO2 by doing direct air capture with the same power.
BTW - there is a tradeoff between grid and hydrogen (in the renewable energy lingo, it is called electrons versus molecules).
Renewable power, unlike fossil fuel power will be generated many miles away (and much of it in the oceans) from human settlements. So the question keeps coming up - which is more economical : And Electrical wire (grid) or convert that Solar/Wind energy into Hydrogen and transport through pipes ?
Right now that break-even point is around 4000 km. So if the Renewable energy needs to go 4000km or less, then Electrons (grid ) is a more economic option. If more, then use that electrical energy at source to electrolyze water and transport the hydrogen in pipes.
The good thing with hydrogen is that it can be stored ( unlike electrical power). Batteries at Grid scale are currently not there.
There is also talk about integrating the grid: for example : when it is getting evening in the East Coast, the west coast / central US have peak sunlight and solar power.