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No. It's not.

It's because solar and wind deployment started to accelerate almost just two decades ago, and the total renewable was too small to hit over the growth of total consumption.
Because world population is still growing and developed countries are still growing energy per capita. It has a top, as children per woman has already peaked and developed countries has stabilized their energy per capita time ago. But that scenario is at least half century, probable one, to reach a worldwide peak of consumption.

In other words... We need time to escalate production every year to start to add quantities enough big to grow faster than the global demand. That point will mark the moment in that fossil fuels will decrease every year.

But as renewable grows exponential, it can go from insignificant to minor player, to major player in few years. We are in the minor player stage, while just ten years ago where in the "insignificant" category.

https://ourworldindata.org/renewable-energy

That time when fossil fuels won't need to grow more will come very soon.

https://edition.cnn.com/2023/12/15/busi … index.html

You can find a variety of forecasts, but most expect coal to peak at less than one decade. From this year up to 2032 in worse case scenario (of serious studies, not propaganda), just because the assume different scenarios like the renewable growth or the economic growth that change the numbers.

Not even one considers than renewable doesn't reduce fossil fuel consumption. And intermittency only has serious consideration when networks has beyond certain levels of renewable. Definitely is not a problem for a network with 10 or 20% renewable.
There are multiple strategies to that scenarios, but we aren't there yet, so as an argument about why now.

But take notice that:
- Renewable impacts more over coal (electricity production competition)
- EV impacts over oil (fuel competition)
- Stationary storage will impact over natural gas (electricity on demand competition)

Different technologies, different stage of development, different effects. That's the reason because we shouldn't expect natural gas to slow down in short term, while oil it's quickly entering in the doubt phase as BEV are growing faster than previous predictions.

That doesn't mean that coal, oil and natural gas is only used in the sectors where there is this competition. It's just that sectors (electricity, mobility and electricity power management) has a significant consumption of these resources so the removal of that will push further reductions. Besides that other sectors has their own battles. Just they are less known and more specific.

There is no need to repeat ourselves. It's enough short term to just wait some years to see. Of course we will need to wait at least other two or three years to confirm the new trend, but... close enough I guess.

Or storage.
Or management on the demand side.

Not necessary modest in the electricity mix. And with electrification, at the whole consumption.

That's true, up to certain point. It require some investment but...

That's depend of the cost of renewable and difference between renewable and fossil fuels, that bets bigger over time. That's the reason why now renewables are being installed a lot more, besides it depends on the mix and percentages among other things. The savings are significant and growing with the new prices. And there are other considerations, as geopolitics.

About that...

Europe electricity market works as a marginal market where the most expensive technology it produces, pushes the prices up.
When the conflict raised, the marginal market model did that natural gas raised the prices way beyond the real costs to pay the gas.
A marginal cost market overreacts under a fuel problem, while on the other side, stimulate faster replacement of the problematic source.
There is discussion about the convenience or not of that model.

Anyway, what it exposed the problem was that we need to remove natural gas as fast as possible. As I said before, that role should be provided by batteries (at least in the electricity market. In industry sometimes is electrification, other is hydrogen if it's for some roles in industry).

At the end, the conclusion in Europe is just the opposite of you said. We need to reduce the dependence from fossil fuels even faster than previous considered if we want to reduce our exposure to volatile fossil fuel prices.
The high prices came from natural gas, not from the renewables.

More expensive infrastructure, cheaper energy. Long term investment.

Hydrogen? Definitely not. Electric heating yes. The use of hydrogen would be used for things like reduction (for steel as an example) or just as a source material, as it's already used, like in the fertilizer field.

And that has being replied before. The numbers are under discussion, but it doesn't matter, as from a long term perspective, all of this enter into the circular economy and next time mining would be a lot lower than the first time.
With fossil fuel, you are just spending time in a dead end way of doing things, doomed to be abandoned after the lacking of fossil fuels and doomed if they aren't replaced on time.
And that's the reason because we are doing this now, and not when the fossil fuel reach prohibitive prices.

Not hydrogen. But just 1:1 electricity-heat.
And even with that, the total primary energy per capita will be lower than nowadays. So... Yeah. That's the plan.
A lot more electricity, a lot less thermal energy (fossil fuels = 0... that's the goal, but still biofuels and biomass in small scale).

Under a linear projection of consumption, which will be only true if the copper reserves works well and prices don't rise up like crazy.
If that's not the case, or if investors considered that a significant risk in the time of the investment, they will push for adoption of a different level of usage, so linear projections of copper usage won't apply.

You are insisting in a linear projection of consumption, where a car or renewable has the same amount of copper per car or per power unit of generation.

Ah.... I feel I repeating the same again and again. I think I'm gonna stop here, because it's the same over and over.

Just, as I said, in just some years, we will be able to see a clear peak on some fossil fuel sources, like coal.

Then, will you recognize at least than renewables reduces the consumption?

You should... but I guess you won't.

Of course we will need a lot more.

And?

You can multiple even by 4 the consumption. It's what will happen probably as a lot of primary energy shift from thermal into electricity.

Of course, with the scale, the numbers are not linear. Because it's very probable that copper will turn less competitive than aluminum in that context, so we will mine less than the linear projections, and more aluminum (it's a guess, but a reasonable one).

Aluminum is not even close to have a problem with reserves.

We will stop to spend energy and resources in some areas, like fossil fuel, and expend on another, in this case electrification.
Deploy renewables consume resources. Stop using fossil fuels save them. It's a trade off.

The difference is as we approach high levels of deployment, more and more circular economy gains weight. The numbers under the first deployment stage are different from a second time.
Also it's not a sudden transition from fossil fuels to renewables, but a gradual one, when some resources less weight and others gains in exchange.
And yes... Metals gain weight in a renewable scenario. A lot.

You are thinking in the extra energy invested in more mining, but you also must account the mining we won't do (like coal) as the emissions associated with that, including the direct consumption of that resource.
Replace coal for renewable SAVE a lot of GHG, no matter you add more emissions in the mining stage.

If you only adds the new consumption but doesn't remove the old one, of course you will obtain that the transition has no sense.

But that's not how it works.

Ah. I also add that, of course, in the future, we will use a lot more aluminum than copper as you have guessed previously (I guess because it's a common argument against copper exhaustion)

How energy expensive is aluminum?

https://www.aluminium.fr/en/stake/energy/

13.5 MWh / t

So 13.5 kwh per kg. The previous numbers are not very different changing copper by aluminum.

The energy is not the most important criteria why we use copper today instead of aluminum. Copper is just has advantages in other aspects, so change will require new developments to mitigate the disadvantages of this material in certain usages.

The most important aspect is the greater oxidation of aluminum and sensibility to temperature changes vs cooper.
Solutions? How knows. New alloys? Better coatings? Sealed products?

I don't know about these things, but I know it's foolish to expect no changes and project linear numbers of consumption. It has no sense as exhaustion raises the prices, and higher prices stimulates solutions and changes.

It will be the same for PV panels, for example. They use around 20 grams of silver per kwh (although this number is changing quickly, the total power change even faster, so the consumption raise quickly).

For silver market is a great stress, so I expect that they will remove silver sooner than later. But panels with copper instead of silver has being developed already. It's just the price of silver is not important BY NOW, so there is no enough pressure to manufacturers to risk about fundamental changes in the panels that could bring new unknown problems. Until the price don't raise enough, they won't take the risk of that change.

With copper vs aluminum in things like wiring you can expect more or less the same evolution. First copper should raises significantly above aluminum alternative so it compensate the costs of the new problems. Then, as the market shift, there is a flux of money that helps in get better aluminum wiring and integration in products.

And to expect that humankind won't find solutions is the classical bet against humankind ingenuity and too much conservative considerations about the nonexistence solutions.

By the way, we have a MAYBE potential technology in the wiring area. Carbon nanotubes. Pretty much a lab curiosity by now. CN wiring already exists but it's not economical by far, so for now it's out of consideration.
Still, it's worth mentioning as the problem of CN is not the source material, but mainly manufacture. A breakthrough in this area could add a new contender to the wiring materials.

As I said... I don't bet against humankind ingenuity and non-existent solutions.

They are a lot of press like that in the past.

As soon as a couple months of bad data shows less numbers, they create a "news".

This is not even a year-to-year data.
Sell at loss... I hear that bogus claim for near a decade already. Pretty much from the beginning. It's obvious that it's a false claim or they would broke already.

Like this

https://www.cnbc.com/2015/08/10/tesla-b … -sold.html

Pretty much the same claim over and over and over. And at least on that days, Tesla burned cash as crazy. It's not that they sell each car at loss, but they invest so much money into expansion that they went into loses year after year.
So the value of the company raises a lot, even if their net income were negative.

After so many times reading the same claim and showing the same result the next year, as you can understand, I'm a bit skeptic about it.

The projection is based in current reserves which seems too conservative. That number is probably underestimated, and even with that, it's more than enough to supply the market for three decades, that it's more than enough to develop any other battery solution if it were needed.

Also that projection is based on certain proportion of lithium per kwh that could change in the future. The number are not rigid. That's not how the market works.

How about the periodic table?

Do you know that theses products uses a lot more scarce elements than lithium?
https://library.ucsd.edu/news-events/wp … 68x542.png

Of course the solution is always the same. Reduce the consumption with better strategies, recycle the elements so the same material can be used again and again or just replace the element for other better suited in the new scenario when the old is not right anymore.

That's the reason because we are trying to make fossil fuels obsolete in first place. Climate and avoid future scarcity.

That's the reason because we need develop first the best ways to extract with the minimum energy and make the recycling industry to reach very high values. Now is not convenient because the recycling industry is just in the starting stage and we have cheaper sources.

So the real lifespan of that lithium will be a lot longer that just looking at the first usage of the material. So a high extraction cost could be compensated by a very long lifespan of the raw material (not the same that the product as the raw material is recycled a lot of times).

In any case, as I said, we can expect the reserves to increase in the near future. Only after sometime, the estimations will turn more precise and we could estimate of the Bell curve applied to the discovery and extraction of reserves, much like in fossil fuels. In lithium we are just at the start of the curve with unreliable data.

Did you notice that in sea water i said BILLIONS?

That's three order of magnitude (x1000) greater than (current) land reserves. That's a good reason to doubt about the reliability of our current data of land lithium reserves. Too much disparity between them. Sea water is easy to estimate, as lithium is dissolved, you just need pretty much multiply the lithium in a small sample to the size of the sea water. And the error margin is not too big. On land things are a lot more complicated.

But anyway, even in the most conservative estimations, the quantity is more than enough to serve the market for a long time, enough to develop other alternatives. That's the reason because nobody inside this market is specially worried about these numbers and focused on short term circumstances like the deployment of resource extraction, which can be lacking in a faster growth than expected scenario.

Let's put real numbers here.

CATL battery manufacturer is currently manufacture sodium ion of first generation with announced values of 160 wh/kg. That's the manufacturer data. And they said that they are working in a 200 wh/kg second generation.
That's pretty close values of low-end/old LFP lithium-ion. Not half.

They are worse in the volumetric density, but that's not a big problem in a long term scenario. That's because other this could be changed, like make the vehicles bigger (not heavier). Just, it's not convenient now. It required to develop new vehicle platforms if you intend to use sodium-ion for long travel vehicles, so for now it's just better to wait to see what happens with battery evolution and lithium reserves.

In any case, sodium-ion seems more than enough for city-type vehicles and we will probably see this kind of vehicles in the coming years. And probably sooner in recent developed countries, as old ones have people with old behaviors and will generate more resistance to the changes.

They are making NOW the first sodium-ion generation.

https://www.youtube.com/watch?v=LxKtCquWx5c

Notice that this announce was from two years ago. The production is happening now.

You are clearly based on biased that, so you obtain wrong conclusions.

People a lot more informed than us is working on this. The numbers you are saying are wrong. And the resources of fossil fuel are clearly a lot more problematic that these other numbers about EVs.

The workers in this field is not worried about lithium. There is more than enough lithium for the coming decades, and electric vehicles don't require lithium but batteries, whatever elements it uses. They are plenty of alternatives.
They are some worries regardless of the speed of deployment which can spark new peak prices (short term, but still a problem for the industry), but that's a completely different thing.

It's matter of money. The more expensive the elements are, the more investment will be in the battery market what will turn into better reduction, recycling or new battery alternatives.

That's how EVERYTHING works in the market, including that whole list of technologies that you mentioned before. Including electronics.

If humanity were unable to find substitutes for current electronics, as an example, this technological civilization would be doomed anyway, regardless of electric cars and everything around that.
Not to mention a long term space program.

We need to move forward finding substitutes when they are needed. That's the main reason I personally doesn't understand why are you here. That kind of fixed mentality, basically luddite, is incompatible with a long space program.

A long space program requires a long term civilization, and a long term civilization require a circular economy with "100%" material recycling.

Understand that 100% is not necessary done with just direct recycling which is impossible, but with a recuperation for disperse sources in a long term endless loop. Because disperse are more expensive, to make numbers works we need that the direct recycling reach as highest numbers as possible, so disperse materials will need only to replace a small fraction of the total.

We know that the model works because nature has done before. The question is not if it works. It does. The question is if humankind will be able to replicate the model in a high developed civilization fashion (the old one based integrated on nature also works... just it's not desirable)

And that model clearly pushes for a change in our energy model among other things. Electrification is a step in the right direction as it's compatible with a circular economy. Fossil fuels don't.

I'm not an expert of copper, besides you are doing a inflexible mentality.
Maybe better technologies of extraction will make it profitable. Maybe batteries (like sodium) will replace copper with aluminum in cells. Maybe they are other resources there that have more sense to extract. Maybe the recycling will be a more economic solution.
How knows whats the right path? We will try everyone and the right ones will triumph. Probably multiple does as they are compatible.

The madness is to don't develop (not even try) a solution and walk a path we know for sure is a dead end. That's fossil fuels.

Yeah. It does happens when there is NO demand. TODAY.
Last lithium related infrastructure is very recent in construction, as the high demand for lithium is also very recent. The same could be said for sodium.
Just wait and see. If sodium-ion demand soar (and I see strong indications that this will happen in coming years) the facilities will be constructed in year timescale.
It's not like the raw source, sodium chloride, pretty much sea salt, is lacking.

You are clearly using bad data.

https://www.youtube.com/watch?v=kIaHEPeBvLU

If there is a reason for sodium-ion to have modest demand is that lithium is plenty, so there is no need for sodium. If the price of lithium goes up strongly again, sodium-ion manufacture will rise quickly if there isn't unknown problems.

Definitely, if there is no hidden problems, sodium-ion seems a better solution of stationary storage energy than lithium. Volumetric density is clearly not a problem for stationary storage. And if that market explodes, that will also push for better sodium-ion batteries how could be enough to make it a viable candidate for high performance vehicles when now is lacking.

Well. I did already X-D

Because it's a non negotiable long term goal. Circular economy is required to achieve a long term civilization.
Other way, you will exhaust the resources and crumble. It's pure math.

Materials, except on nuclear reaction or atmospheric looses, are always there. Exhaust is just a name for "reduced accessibility", as every atom is still there. Just in a open loop model, like fossil fuels, they are more and more difficult to regain the original state more convenient for our civilization.

That's what a circular economy concept is. To reach a level of energy requirement enough low to be able to close the circle of 100% reusing materials and support our own energy infrastructure and everything else running. Other way we will lack energy to recycling 100% and the accessibility will go down, which will turn in less access to materials over time until crumble.

And while we think in short term because humankind variables changes too fast, on a civilization scale, long term space projects like terraformation require a complete different mindset.

As we don't know the future speed of humankind, the most we can do is to estimate requirements and goals we need to reach, and just do whatever small step is in our current reach.

And one clear criteria is circular economy. Without that, any other plan is doomed to fail. It's not necessary we reach a perfect circular economy in a specific timeframe, but we should avoid to reach a resource trap that force us to go some steps backward before try it again.
Worse case scenario our civilization can crumble, and next time we won't have easy accessible fossil fuels, neither high volume of concentrated scarce materials, so the only path we could take would be extract very disperse sources, concentrate and maintain in the high recycling loop growing in the accessibility to materials over time.
It's just... this alternative plan seems terrible slow. That's the argument because some people think this is the only chance humanity can develop that kind of sustainable high energy civilization.

I don't think that way, but I understand that it's a lot more difficult than this first chance humankind has.

So... you are worried that lithium with a limited usage and a long lifespan per product will deplete but you aren't worried about fossil fuel depletion where we currently are a LOT more dependent from fossil fuels, it's used daily based (a disruption generate a great short term problem) and there is no possible recycling of that.

You are clearly using two different ways of thinking for both resources.

We are doing the same that when we went to Moon.
We make a goal (push for circular economy compatible solutions) and make one step at a time to walk the path of the goal.

And the goal is not EV itself, but change every technology to be compatible with a circular economy model.

As I'm sure you know, there are also people that insist in try to make internal combustion vehicles circular economy compatible via alternative fuels. If you are convinced that it's the solution, you can try it. Nobody is gonna stop you trying that.
It's just most people see EV a better solution than e-fuels or hydrogen fuel cell vehicles. The market is there for you to try and prove others they are wrong.

For me, it's pretty much the same, if we reach sustainability through one path or another. I just know that the true path to a dead end is to maintain the current model.
And from my current knowledge, EV seems like the best solution until now. Well... It's happening. Just in the beginning but it does. Past year 2023, 9.5 million BEV where sold. And the market is growing.

Your alternative is to remain in the same path over endless excuses and bad data, to retain in the fossil fuel industry.
That "plan" will only work until the total fossil fuel production shrinks, that it's just some decades far away from IAE estimations even in the business as usual estimations and later, going down the curve trying to develop what we can do now, in a worse scenario.

Do you understand why now most of the planet disagree with your opinions and consider that the madness is not the electric vehicles but to maintain the old model at all cost?

Probably not.

I recommend you to search the data by yourself. It's clear that you read too much FUD from anti-EV and anti-renewable.

Anyway, what we can think or write doesn't mean nothing. It wont' change the path we are doing. EV is growing because it's working.
If that problems you claim unsolvable turn true, EV will met its end sooner than later.
But I won't put my bets on that. I prefer on bet that humankind will develop a circular economy, and BEV vehicles seems like the right technology to that goal today in that specific market.

Of course, to reach a circular economy we need to change A LOT of things. We are doing steps in a lot of other fields too. Just there is a lot of noise around the EVs.

Mix old and new energy doesn't help to view the right picture if you don't understand the kind of curve is happening.

In 2000, solar was almost prohibitive. On 2010 was non competitive without subsidies. On 2020s solar is the cheapest source of electricity in a lot of places of the world.

https://en.wikipedia.org/wiki/Growth_of_photovoltaics

The installation of renewable is exponential. That's the reason because old numbers seems negligible, while current numbers are really significant, and it will become even more important in the future.

Don't use median numbers with an exponential. It doesn't work that way.

The same is applicable to the consumption of raw materials. It's not the same the production/materials of 2000s technology than 2020s techonology.
In general, there is no pressure to reduce consumption if it doesn't generate too much cost impact until the price of the raw material raises.

The best example of that is silver in PV. The silver in PV has being shrinking constantly, so the cost impact in the PV has being contained while the price of the silver has gone up by a lot.
The market is big, and there was people who tried to build PV panels without silver at all. And they work to certain extend. But the market didn't buy it because not even a small  risk of raising failure make it non interesting with current prices and usage of silver.

But... what would be happen if silver will raise a lot more and/or PV with silver reach a physical limit to reduce the quantity? That kind of PV without silver would be a lot more attractive and it would be adopted.
There is a high chance that this will be happen in the future.

That's the reason because just multiply current raw usage per watt of current or past technology by the power need to power the entire civilization is a very wrong way to "predict" the failure of green energy. It won't work that way.

As soon as some raw material become expensive, the people involved start to investigate new ways to do the same things without the same bottlenecks.

Cobalt become expensive for electric vehicle batteries... They push LFP battery technology.
There is risk of lithium bottleneck... They research sodium-ion technology.

Etc. etc.

The technology of hundreds of megawatts and hundreds of terawatts would be very different in the implementation, even if it's the same idea in the core.

To believe that the green energy researchers and developers won't be able to adapt the technology to the resources available is a blind assumption of technology failure.

It's paradoxical that a forum participant about space exploration and mars colonization use technology pessimism as an argument.

In short term, space deflectors could be the least expensive solution, but in long term, it requires constant maintainance, so it should be best to find some ground solution.

I guess restarting the core is just beyond our capabilities not only now but on millennia scale, and the resources invested is just so crazy that it makes undesirable. But maybe we could do the trick if we could magnetized bit chucks of the crush with ferromagnetic deposits in a very specific alignment so the combination of the fields could approximate to a core-like planetary magnetic field.

But it's related to the topic.

Methanol and synth fuels use hydrogen-electricity for the synthesis. It's the most difficult part to reduce the prices, and it's linked to electricity.

Most projections about synth fuels to become cheaper is because they expect renewable or nuclear energy to become cheaper.
But at the same time, this scenario means that electricity should be cheaper too.

Fuel synthesis always require a less efficient route than a battery route. Create chemicals and burn them is less efficient than electric storage. So, no matters how cheap methanol turns, electricity storage will always be cheaper.

It's relevant because you can't compare today prices of electric cars with future methanol cars, because optimistic projections for methanol means optimistic projections for electric cars too. It will remain uncompetitive no matter how much electricity prices drop.

That's a good argument why it's very difficult for methanol/synth fuels on a future scenario to have a big fraction of the vehicle market. It could be interesting for other markets where batteries are not suitable because lacks of enough energy density like airplanes or maybe long range ships.

But physics doesn't forbid anything of that. Biases does.

I see electric cars working perfectly now, and I didn't see "Mr Physics" appearing screaming to forbid it.

What did you expect? You live in a world that works mostly on fossil fuels, so every industry, including renewable, using a lot of fossil fuels in the process.
But also uses electricity in a lot of steps of the process... And electricity has partially renewable based.
So, over the same argument, fossil fuels also use renewable energy embedded.

That's a sophism in a broader sense and doesn't means nothing. The thing is that the process to build renewable doesn't require fossil fuels. It uses because our current model uses.
It could need carbon materials and energy for sure. But that doesn't need fossil fuels per se.

In fact, most steps could be changed into electricity based alternatives that are more efficient with cheap electricity. Obviously, that isn't right if the electricity is fuel based from start, so the electricity generation is more wasteful than use the fuel directly in the industry.

But with renewable becoming more and more cheap, and fossil fuels becoming more and more expensive, there is a time where using renewable electricity in a electricity based industry is better and using fossil fuels in a burning fuel based industry.
Things like produce cement or steel will use a lot more electricity and a lot less fuel in next decades, because of the change of the energy mix of this future.

And the rhetoric of "renewable use fossil fuel" will turn false one step at a time.

As an argument about "because that renewable can't work" is flawed.

It's three orders of magnitude higher, but send volatiles from Jupiter are around 100-200 MJ per kilogram.

This is a backup plan if there is no enough volatiles on Mars to terraforming. The energy is a lot less if use near Mars objects but they are scarce and it needs to be moved through rockets

A Ganymede-Mars system could send volatiles using a rail launcher. No rocket equation is used here so just kinetic energy of a transfer orbit depending of planet positions. The decomposition of elements is not necessary. The kinetic energy is far above the requirement, so the impact or friction would be more than enough to do that.

Solar energy income is on the Petawatt scale so ignoring the economic problems of doing so enormous task (we can assume that we could develop a exponential robot workforce on space so the limit are resources and energy, not time)... Petawatt its the reasonable amount of power that we can use on Mars without generate other side problems.

I guess the best plan is use the most efficient way to reach minimal deployment of a semiterraformed Mars (life tolerant, liquid compatible) and use later the "unlimited resources" plan and import as much as needed to reach a complete Earth-biocompatible planet, with no water restrictions, nitrogen and oxygen.

Earth means a huge deep gravity well... a lot of delta-v.

There is plenty of places to get water... farther but with less energy cost.

And the gravity well means that without some megainfrastructure like space elevators or something like that, or a new kind of propulsion technology, you need to use chemical rockets to go beyond the well...

Total waste of resources.

A lot better to use rail launchers or tethers on outer moons or Ceres and use powerful engines only for minor corrections (or maybe even lasers to eject some material from the "asteroid pellets")
Consider that any terraforming project, even minimal means a LOT of mass.

I guess you didn't understand my idea, because the tensions are far lower than a space elevator.

I checked the numbers. Use 1g means too big tower, but 3g make a very reasonable idea.

I will explain again.

First, the principle is just like a gigant carousel, like a double sling , with seats attached to the top. Use two opposite launchs are just arbitrary to make it a central point of gravity. Another configurations are possible.

Using a gravity spin calculator

https://www.artificial-gravity.com/sw/SpinCalc/

I will use 1400 m/s as tangentian velocity as a orbital speed reference.
3g of "gravity" - because greater accelerations means less cable and lower tower (and the tower is high in any case)

It gets ~66,6215 km of radius.

This is for zero gravity.

Ok... This will be built on the Moon, so on the parallel plane, the launch objects needs to separate that 66.62 km from the tower to reach the 1400 m/s of tangential speed.

Because we are on the Moon, the cables won't be parallel to the surface. In fact, it will be in a triangle represented by the two perpendicular vectors. Pseudoacceleration (3g) and Moon gravity (~0,166g)
So... 66,62115*0,166/3~=3,6864 ...

The cable will be a total length of: sqrt(66,62115^2 + 3,6864^2) ~= 66.73 km

A tower 4km high could work.

It's very high. Higher that any tower in Earth (0.8298 today) but it would be just a structure AND Moon low gravity helps a lot.

So, we just attach opposite cargos to the both cables, we make it spin faster and faster while the cables extends up to 66.73 km (it will never touch the surface because at that speed, only will be at 4-3,6864 distance), with a increasing perception of acceleration (centripetal acceleration) and, just release.

1400 m/s. Enough to put in a orbital position. Although it would be better to have some propulsion and use the first orbit to raise the perihelium. It would be very, very low and a collision is possible in the next encounter with the lower altitude.

The weigth that the cables must endure are just the weight of cargo at 3g plus the weight of the cable.
Less than 70 km cable. Not too much.