China’s Space Ladder Vision Would Be a $200 Billion Space Shuttle Mistake

China has been pretty good at large engineering projects. Readers of Nextbigfuture over the last 15 years know that Nextbigfuture tracks all of China’s megaprojects and all of the major space, energy and technology projects that have ever been proposed. China does not have infinite funds and I will go over the fundamental engineering, science, technology and economics problems.

Xinhua released a video where China is proposing a earth-based space elevator that they call a sky ladder.

In 2018, I described the economic and technological reasons why an Earth Based Space Elevator is a bad idea and would be an engineering mistake.

In 2018, China’s researchers created carbon nanotube bundles that have a tensile strength of 80 Gigapascals. This is wonderful we have materials that would theoretically be capable of making an Earth-based space elevator.

We just need to economically produce thousands of tons of the material economically. We also have to put them together into a structure that will stretch out for 40,000 to 60,000 miles. It has go past geosynchronous orbit to reach the counterweight. Geosynch would just be the gravitational midpoint.

A lunar space elevator has not been built. A lunar-based space elevator demonstrator could start off with far less material and we could start with material that we have in sufficient quantities. We could build and deploy a basic lunar elevator for $1 billion.

Here is the 17-page spaceline proposal for a lunar elevator.

Many lunar space elevators have been proposed and have had some NASA studies.

None of the lunar space elevators have been built and few of the technically feasible components have been built.

China spent a trillion on high-speed rail lines using well-known technology and cement and steel from 2013-2021. China built shorter high-speed rail lines than the 40,000 mile length of the proposed space elevator.

No Space Elevator has ever been built and we have almost none of the required construction materials.

A 24-mile bridge was built in China for $2 billion. One mile long bridges in the US can cost $6.5 billion.

$10 billion cost estimate for space elevators are silly and insane low-ball guesses.

If nanotechnology advances to make that much super-strong materials then vastly improved reusable rockets could be built or super cheap space planes would become possible that would be even lower cost.

The US spent $200 billion on the Space Shuttle program. The Space Shuttle program was justified as a partially reusable “space truck” that would operate at $5 to 10 million per launch in 1970s dollars. Space shuttles ended up operating for about $1 billion per launch. The actually price of things matters. Buying something for $10 million might be great and profitable but buying the same thing for $1 billion can be an incredible a waste and stupid. A Space Shuttle launch for $1 billion each was a waste and was stupid.

The US also spent almost $200 billion on the International Space Station. The International Space Station was supposed to be a needed staging point to allow for eventual moon base support and larger space operations. The actually really useful space work never happened. We were left with VASTLY overpriced place for low earth gravity work.

Space shuttles were built and used. Throw away rockets could have been used instead of the shuttle for those missions for about ten times lower cost.

Mass Producing Fully Reusable SpaceX Super Heavy Starships

The estimated salary, benefits and overhead are an estimated average annual cost $200,000 for each SpaceX employee. This means that the 3,000 employees building Starships would be $600 million per year. If there were 100 Starship built each year and 20 Super Heavy Boosters, then each Starship would have about $4 million in labor and each Super Heavy booster would have about $10 million in labor. If the production rate was halved and the staff levels were the same then the labor for Starship would be $8 million and the Super Heavy booster would be $20 million.

The steel is about $200 per kilogram. The dry mass of the Starship will be about 120 tons and the Super Heavy Booster will be about 300 tons. This would be $2.4 million for the Starship if most of the material was the steel alloy. The Super Heavy would be $6 million of steel.

If the steel and salaries are half of the total cost of the rockets then the unit costs at different production levels would be:

Two Starships per month would mean $37 million per Starship
Two Starship per week would mean $13 million per Starship

Reaching a Starship cost of $5 million would require 3000 employees to build about 300 Starship every year. This would be $1.3 million in labor, $2.4 million in material and $1.3 million for other costs.

Each Super Heavy Starship that could fly to space once per day would take 100 tons to space for about $200,000 in methane fuel and $300,000 for amortized asset and other operational costs. This would be $5 per kilogram or $12 per pound to orbit. This would be far less than the promised $35 per pound of earth-based space elevators after all the imagined space elevator development and imagined construction.

But now we are beyond the paper project stage for space elevators are at the video animation stage.

SOURCES- Arxiv, Xinhua, spacex, NASA
Written By Brian Wang, Nextbigfuture.com