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#1 2022-06-18 14:49:04

FriendOfQuark1
Member
From: Houston
Registered: 2020-11-04
Posts: 5
Website

Large Ship Finance

Team,

I come this way via the North Houston National Space Society chapter.  We have had in recent months presentations by New Mars members on "Big Ship" and "Big Ship Propulsion".  Both of those topics are above my paygrade as more of a lifelong accountant.  I will be following up on those two talks with "Big Ship Finance".  Designing the things is one thing, and paying for them is quite another.

I'm fleshing out a talk that is hopefully highly interactive and accessible to laypeople. 

The two main assumptions I've settled on so far is the competing 500 person version (because it uses no precision materials/methods) and Dr. Johnson's calculations for chemical propulsion.  That is probably slightly more expensive than more exotic propulsion but I feel it is easier to attract financing for known and proven methods.

Hopefully, I will begin building out a preliminary outline for the powerpoint in this space tomorrow.

FoQ1

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#2 2022-06-18 15:45:17

kbd512
Administrator
Registered: 2015-01-02
Posts: 5,693

Re: Large Ship Finance

FriendOfQuark1,

Welcome to the New Mars Forums!

We're looking forward to working with you.

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#3 2022-06-18 18:45:30

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,674

Re: Large Ship Finance

Now its going to get interesting FriendOfQuark1, and a happy welcome to NewMars for sure.

Louis has been the main poster about ways to get financing or in many cases covering a broad range or methods and tier levels.

here are some of those topics

MIT (Money, Investment and Taxation) - Fiscal Planning for Mars

Why is a Mars currency important to the development of Mars?

A Mars currency

Mars Economic Activity

Sagan City - what will be there?

Budweiser on Mars

Sponsorship for a Mars mission

The University of Mars

Happy Reading...
There are many more posts hidden with in topics which are of a financing aspect.

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#4 2022-06-20 11:09:55

FriendOfQuark1
Member
From: Houston
Registered: 2020-11-04
Posts: 5
Website

Re: Large Ship Finance

OK, I'm behind schedule.  I'm going to start with a brain-storming pile of disorganized thoughts - with a goal of cleaning this up into a 30-45 minute presentation for NSS North Houston.

First things first - dependencies.  I have the cost estimate for the 500 person big ship, which I will add a 33% fudge factor to.  I still need to get the weight of the ship and run Dr. Johnson's calculations on how much fuel we are talking about and get a cost estimate, plus estimate for the "tug".

Acknowledgements: Get permission/pictures of contributors, included for the two previous talks and acknowledge their contributions to this complex project.

Interactive moment: Ask audience to name some of the largest financed projects they can think of.  Show slides of Pyramids, Great Wall, Hoover Dam, Interstate Highway System,(large) Vegas Casinos, Titanic, QE2, Shell Prelude, Boeing 777, Apollo Program, etc with cost estimates converted to 2022 dollars.
-Compare those figures to our three part cost estimate for ball parking and establishing that financing is in fact plausible.

Make presentation academically robust (in line with NSS educational mission) by educating the audience on finance theory, including the theoretical components of an interest rate.
- estimate those components for our project (SWAG)

Main potential sources of funding:
-Government (pros/cons)
-Insane billionaires (interactive moment - question audience as to who their favorite billionaire space cowboys are)
--Musk
--Bezos
--Branson
--Dark Horses
-Crowd sourcing (compare to largest successful CS program ever to establish implausibility)
-Debt
--[EDIT]Include an initial period with PIK bonds?
--Discuss colonization (including debt finance of passage) of the New World as an analog
---The role Lloyd's of London and the development of Insurance playing a key role (source material "Against the Gods; The Remarkable Story of Risk")
-Establish which blended approaches are most probable; handicap as percentage (SWAG)
--Interactive moment - ask audience to give their own handicapped percentage of which approaches will prevail - why? (discuss)

Establish the time frame for financing, interest rates, and economics of a ~40 year ship(s) life
-Estimate one way "ticket" price (x500 passengers) that makes the program economically plausible
-Include cost of fuel for each trip in calculation!
-Explore how building multiple ships changes the economics
-[EDIT 1.22PM Local time] ask around if a "discounted cash flow analysis" is 'interesting' or 'too academic/dry'
===================================================

Board input, especially on missing elements is sought.  Fire away!

Last edited by FriendOfQuark1 (2022-06-20 12:26:20)

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#5 2022-06-20 13:50:49

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,674

Re: Large Ship Finance

Not sure what was the difficulty you had for getting back on but it seems its been resolved.

Thanks for the list of the wealthy to target down through to crowd sourcing.

RobertDyck's ship is still in flux but in general terms its ready to continue pushing concept forward.

I think the over all goal still fits with in the mass estimates of the 5.000 mT even if its shape gets altered to benefit the performance that is desired. Cutting the first goal of 1,000 back to 500, was a means to the goal for life support and more in terms of mass required for all aspects.

I hope that you get more out of the louis topics as well for ideas.

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#6 2022-06-20 14:00:38

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 10,397

Re: Large Ship Finance

With thanks to both FriendOfQuark1 and SpaceNut for building this topic...

As a reminder to forum readers ...

The large Ship concept in development by RobertDyck is for 1060 passengers and crew, with a mass of 5000 tons. Large Ship has a distinctive design feature of Unitary Rotation.

The smaller ship concept in development by kbd512 is for 500 personnel.  It features a dual habitat counter-rotating design. 

While kbd512 is thinking about trying to propel his ship with an all electric system, the Large Ship design is to be propelled entirely by proven chemical means.  The lead NewMars member working on chemical propulsion for Large Ship is GW Johnson.

FriendOfQuark1 has decided to build a financing plan for the smaller vessel using chemical propulsion.

If anyone has skill with graphics for computer presentation, we have an opportunity shaping up to assist FriendOfQuark1.  To my knowledge there exist no graphics or animations showing the 500 person vessel imagined by kbd512 on it's way to Mars, at Mars, or on it's way home.

(th)

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#7 2022-06-20 14:50:30

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,674

Re: Large Ship Finance

Kbd512's design is more of a quick transport out to mars and back with mars set up the pie to win.

RobertDyck's is more of an long goal continuous use capable of supporting and sustaining without resupply.

Both are being built on orbit to be able to perform there unique functions of crew and passenger transport. Both must deliver a crew safely at both ends of a trip which means AG (Artificial Gravity) will be used.

At the mars end equipment will be off loaded to mars and will await in orbit until its time to go back to earth.

Both are not using the same means to get from earth to mars for fueling.

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#8 2022-06-20 16:40:35

kbd512
Administrator
Registered: 2015-01-02
Posts: 5,693

Re: Large Ship Finance

tahanson43206,

Target all-up-weight for my ship is 1,000t.  Ship uses laser ablation propulsion that can vary thrust and specific impulse independently of each other.  Ship requires solar-powered laser satellites in GEO or higher orbits generating about 25MWe to produce laser power sufficient to ablate the propellant.  All propellant (Aluminum or Alumina Oxide) is aboard the ship.  A similar laser remote power satellite system must also be in place at Mars.  Laser focuses beam power on a plate of solid Aluminum on the rear of the ship with a high pulse repetition rate to increase thrust without melting the Aluminum, except for a very thin layer.  IIRC, ship requires about 1kN of thrust to achieve escape velocity in about 39 days and some change.  Transit time can be decreased by increasing the laser power / pulse repetition rate or by increasing the number of laser remote power satellites.  All basic experiments to confirm thrust generated, specific impulse, and required beam coherency over target distances have been carried out on Earth already.  All passengers will have to remain in the spokes connected to the counter-rotating habitation rings during Trans-Mars Injection / TMI period for proper radiation shielding, because there's no practical way to carry enough water for ionizing radiation mitigation during the extended transit through Earth's Van Allen belts.  All life support requirements should require about 160kWe of onboard generating capacity, or less, which is exactly what ISS generates.

Life support power requirement was determined by scaling up the ISS-tested CAMRAS / RCA 3.0 amine swing bed CO2 scrubbers, OGA, ventilation fan power, and IWP next-gen / "exploration class" life support systems developed for Orion, Mars space suits, and the Lunar Gateway.  BTW, this amount of power must be generated 24/7/365, without interruption, including when the ship is at Mars, 2X further from the Sun than Earth, and that is how the solar array was sized.

Total ship empty weight target of 250t was arrived at using C250 "maraging" (martensitic aging) sheet steel (250ksi min yield strength), "next-gen" life support systems tested aboard ISS, Aluminum wiring, Nextel/Kevlar "stuffed" Whipple shielding.  Total onboard food and water rations must be reduced to a 1 year supply to meet the all-up mass target.  The ship will nominally be in transit for 6 months and must be braked into orbit around Mars using a laser power satellite permanently stationed at Mars.  Apart from control moment gyros for attitude control and a small electric-based reaction control system for mid-course trajectory corrections, there won't be any other onboard propulsion systems because this greatly increases mass and cost.

We need to divorce propulsion power generation mass from the ship, even if it's technically feasible to include the power generation mass with the ship.  The goal here is to deliver people with maximum efficiency and therefore minimum cost, a modicum of comfort, and exceptionally high reliability.  Apart from low-thrust leading to increased Van Allen belt radiation exposures that must be mitigated, minimum cost all-electric in-space propulsion excels at providing the required thrust and specific impulse for efficient interplanetary transits.

Every bit of dead weight carried back-and-forth between Mars and Earth drastically increases the cost of the mission, which is why we will stop doing that.  This is also why chemical propulsion near the 1,000t payload class becomes very impractical.  Starship has to load 1,100t of LOX/LCH4 to deliver 150t to Mars, so 5,133t of the same propellant would be required to TMI 1,000t, with no possibility of doing anything except aerobraking into the Martian atmosphere at the other end.  The total "dead head" payload will be about 700t or so.  At the 5,000s or so that laser propulsion can provide by ablating Aluminum, a single propellant load is sufficient for spiral-out to Mars, spiral-in to Mars, and spiral-in to Earth without a refill.  Perhaps most importantly, Aluminum propellant is indefinitely storable, whereas cryogenic liquids are not.

This ship is not reliant upon any nuclear power or propulsion technologies that may never see serious development effort in the next decade.  A small space-rated nuclear reactor would obviously be a boon to ship development and possibly propulsion as well, but not required for inner solar system transits.  Apart from the laser power satellites which are technically dual-purpose defense hardware, every bit of the ship technology will be COTS or commercialized NASA space-related technology (CAMRAS / OGA / IWP) available to American corporations and select foreign partners, such as the European Space Agency.  The power satellites can be controlled by NASA, so that no civilians are in control of dual-purpose hardware, and used for various robotic interplanetary exploration or space debris removal efforts as well.

We are not going to reinvent any wheels here.  We need some very pointed propulsion development technology related to creating laser-based solar power satellites.  Everything but the propulsion system will be stock hardware from NASA.  US DoD is already developing the laser technology, which we will need to either scale-up or distribute and coordinate for civil propulsion purposes.  We need engineering development of the ship itself, which will include development of the forming dies to wrap the C250 steel over and then laser or electric resistance weld into place.  If we opt to use laser welding, then we need more precise butt-joint alignment.  If we opt for electric resistance welding, then we will wrap the slit coil sheet steel around the mandrel, then continuously seam-weld a thin steel tape over the joints, which don't need to be all that precise.  So long as the steel tape covers the seam between the inner layer of steel wrapped over the mandrel, it will seal.  We're going to do this from both directions, meaning interior and exterior, so welded sheet steel tape is sealing the habitation ring from both sides.

Megawatt lasers should be ready around 2023 and the SpaceX BFR would be able to deploy them in space

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#9 2022-06-20 17:39:39

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 10,397

Re: Large Ship Finance

For all NewMars members ...

FriendOfQuark1 would appreciate feedback on Post #4

Posts about other subjects may be a distraction.

The structure of the financing presentation is firm:

500 passenger ship and chemical propulsion.

Imaginary future capabilities are interesting but not pertinent to this topic.

We will (probably) have Warp Drive some day.  That is not part of the present topic.

(th)

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#10 2022-06-20 17:57:40

FriendOfQuark1
Member
From: Houston
Registered: 2020-11-04
Posts: 5
Website

Re: Large Ship Finance

tahanson43206 wrote:

For all NewMars members ...

FriendOfQuark1 would appreciate feedback on Post #4

Posts about other subjects may be a distraction.

The structure of the financing presentation is firm:

500 passenger ship and chemical propulsion.

Imaginary future capabilities are interesting but not pertinent to this topic.

We will (probably) have Warp Drive some day.  That is not part of the present topic.

(th)


Thanks TH,

Financing "cost" includes interest rate.  Finance theory posits that interest rate is partially driven by a "risk premium".  My reasoning for going with chemical propulsion is while it may be more upfront cost, and less efficient, its financing overhead will be lower as it is accepted technology.  Once the first ship is financed, more exotic propulsion can be retrofitted (or used on additional ships) for relatively low marginal cost.

The propulsion system above (kbd512's) intrigues me.  I LOVE cool tech.  But for my presentation, I don't want to have to sketch up the cost and financing for SBSP and laser ablation research and development. 

When it comes to modern finance, there are no "heroes" or "creative types" because stepping outside the colored lines tends to land you in prison.  For (plausible) financing, from plausible sources (the "plausible" investor is human with wealth) we need as much "off the shelf"/"widely accepted" tech as possible. [EDIT] - Else, the 'risk premium' grows more onerous...

FoQ1

Last edited by FriendOfQuark1 (2022-06-20 18:02:10)

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#11 2022-06-20 19:13:48

FriendOfQuark1
Member
From: Houston
Registered: 2020-11-04
Posts: 5
Website

Re: Large Ship Finance

NOTE:

My presentation is not intended to produce a bona-fide FINANCING PROPOSAL.  It is intended to educate the public on how finance for big projects "works" in the modern world.  "Proper" risk underwriting is beyond the capabilities of any single human (however assisted by a rabid internet forum).  I am seeking to fulfill the NSS charter to "educate" the public on space topics.  The talk, will thus, be largely theoretical. 

This is by design as accounting and finance are ... sort of ... boring.  I seek to entertain as well as inform my audience.  This is, therefore, not a Master's level finance class presentation.  Some (many?) estimations will be used.  This is also by design as I'm seeking to present a conceptual framework for how to think about financing a 'large ship' in a manner that is academically robust.  The particulars, are clearing still evolving on this forum.  And will continue to evolve.  Thus, a conceptual framework, only. 

HTH


FoQ1

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#12 2022-06-21 04:16:14

kbd512
Administrator
Registered: 2015-01-02
Posts: 5,693

Re: Large Ship Finance

Post moved here, per request from tahanson43206.

Last edited by kbd512 (2022-06-21 19:25:14)

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#13 2022-06-21 06:51:07

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 10,397

Re: Large Ship Finance

For kbd512 re post #12

Your interesting post does NOT belong in a topic devoted to finance.

Please move it to a more appropriate topic.

This topic should NOT be about speculation on possible future alternative propulsion systems.

Posts to this topic should be designed to assist the topic lead to achieve the goal of a presentation to a live audience.

Speculations about propulsion will NOT be included in the presentation, so posts about speculation on propulsion are not helping to move the project.

Please go back to Post #4 and see if there is anything you can contribute.

We (forum) have a rare opportunity to help a member of another group to create and deliver a presentation.

All forum members are invited to assist by studying Post #4 and contributing posts that help to move the topic along.

(th)

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#14 2022-06-21 09:28:18

FriendOfQuark1
Member
From: Houston
Registered: 2020-11-04
Posts: 5
Website

Re: Large Ship Finance

@kbd512

Thanks for that!  I truly enjoyed reading your analysis of the current state of development for ablative propulsion.  That is exciting stuff!  You are clearly very knowledgeable and an asset to this forum.

I however must insist on preventing scope creep for my presentation.  It thus partly (largely!) leans on Dr. Johnson's previous talk to North Houston NSS and his extensive calculations for chemical propulsion needs for a given dead head mass.

Looking forward to anything you might have to add that is within scope!

FoQ1

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#15 2022-06-21 19:00:50

kbd512
Administrator
Registered: 2015-01-02
Posts: 5,693

Re: Large Ship Finance

FriendOfQuark1,

In that case, take the numbers from GW's presentation for the 5,000t "dead head payload" and divide by 6.67, because that's about how much LOX/LCH4 propellant would be required for my ship concept.  Non-millionaires will never be able to afford to go to Mars using chemical propulsion, which is why I don't see the point to using chemical propulsion.  If most people were millionaires, then maybe that would change the value proposition of chemical propulsion.  Unless conventional rocket transport costs go down by another order of magnitude, which seems highly unlikely since it would be below the purchase price of the propellant itself, then chemical propulsion is basically a non-starter.

Why pitch an idea you know won't be economically feasible for any but the 1%, unless that's your target audience?

If the 1% are looking to invest to make money, then who are they selling a service to?

Most rich people get rich by selling their ideas to (mostly) less wealthy people.  Maybe there are a few millionaires selling ideas to billionaires, but the billionaires have a small army of people they pay to ensure that they show a return on investment.

Most one-percenters are actually retirees who made their millions through savings and investments before retirement.

How many of those prospective retirees are chomping at the bit to spend their life savings on a ticket to Mars so they can then start a second manual labor job on another planet before they die?

Then there's this silliness:

The Energy Consulting Group - Methane in the Form of Liquified Natural Gas (LNG) Will Power the Next Generation of Rockets

From the article:

Our analysis indicates that a fully configured Starship launch (booster and Starship) will use about a 1000 tonnes of methane in the form of LNG as fuel.  This is equivalent to approximately 50 million standard cubic feet (mmscf) of methane.

...

Elon Musk, in response to questions during a Twitter interview, indicated "that the spacecraft is being designed with the plan of flying it for an average of three flights per day, each carrying over 100 tons of payload per flight, for a total of more than 1,000 flights per year, per vehicle."

This works out to be about 150 mmscfd per Starship, or about 150 billion cubic feet of methane/natural gas per day (bcfd) for a fleet of 1000 rockets.  150 bcfd of natural gas is roughly equivalent to 25 million barrels a day of oil.  For reference, recent (2019) US demand for methane in the form of natural gas averaged about 82 bcfd.  In essence, Mr. Musk is suggesting that US demand for natural gas could grow dramatically over the next 10 or so years due to SpaceX activity.

...

They're over the mark by approximately 20%, since Starship requires about 800t of LCH4, not 1,000t, but still.

Are we really likely to double our current natural gas consumption on Starship flights alone, or is someone not dealing with ugly objective reality?

Having dreams is fine.  Dreaming big is even better.  Pretending that you're going to double the natural gas consumption of the US to launch rockets into space is wildly more fanciful than using lasers to ablate Aluminum, which is already done every day by the substrates manufacturing industry.

There is not enough natural gas on the planet to support this, so that means SpaceX is either starting their own natural gas synthesis plant in Boca Chica, or we're using a much more efficient in-space propulsion scheme to forego having to double the US yearly natural gas consumption for Starship rockets alone.

You're a numbers guy.  You know how to do basic math.  Someone looking to invest in this idea is going to have their own numbers guy(s) or gal(s) "run the numbers" and then they're going to tell us that we're full of it.

Triple the current US natural gas consumption rate is what launching 1,000 small ships or 200 big ships or 100 really big ships will look like using nothing but chemical propulsion, if the goal is to populate Mars with a million colonists within the next 50 years.  Alternatively, we will need, not "want", drastically more efficient in-space propulsion to get the job done.

I need at least 3 Starship flights to build each of my ships, 2 consumables flights, 2 propellant flights, and 1 colonist flight.  That's 7 launches and 5,600t of LCH4 in total, 4,000t to actually use the ship.  If we launch 200 ships per opportunity, then I need 600 initial launches for ship construction followed by 1,000 flights every 2 years, or 500 per year, which means 4,000,000t of LCH4 (natural gas) every 2 years.  If the ship itself is Methane-fueled, then we will need exponentially more Methane and Oxygen.

Total global natural gas consumption is about 1.5 billion metric tons per year.  The US consumes about 307,500,000t per year, or 20.5% of the global total.  By going with a drastically more efficient in-space propulsion scheme (lasers, ion engines, plasma engines, whatever), we only require 0.65% of the US yearly total.  The all-chemical alternative mandates triple the current US natural gas consumption rate.  You tell me who you think has their head in the clouds.  There's a reason GW said "this is pretty significant", with regards to propellant production rate, during his presentation.  He wasn't lying.

The actual math portion of this post took less than a minute punching in numbers on my calculator.  I spent a few minutes longer figuring out how much natural gas the world and the US consumes every year.  I presume that whomever you pitch this idea to will also have a cell phone equipped with a calculator and web browser applications.  They might listen to the entire presentation, but they'll record it and show it to their number crunchers shortly thereafter.  I'll wager that I'm very very far from the fastest number cruncher in the west.

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#16 2022-06-23 13:59:03

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,252
Website

Re: Large Ship Finance

One of my friends is part of a company that brokers business loans. The company is a broker between those seeking financing and banks or investors. He asked me to consult regarding requests for technical projects. My friend is a former miner, so is able to assess requests for mining or oil projects. For example, one request was for a plant that would convert surplus natural gas into something heavier, such as gasoline. Fracking in the US has produced copious quantities of natural gas, so converting that surplus into something that can be sold is better than just burning it off. I told him I don't know about the financing, but the technical aspects were sound. For the people he deals with, a $10 million project is small. This company has been in business for many years, but it looks like they will actually land a deal. Rather than brokering, his company is buying a gold mine. Investors are highly interested in gold since the economy is going down the toilet. Re-opening a closed gold mine is definitely in his wheelhouse. He has asked me to be a member of the board of directors, and said it will be a paid position once the financing comes through. Lots of delays, but we're still hopeful.

My hope is once this company has proven itself, I would propose founding a company to make products usable on Earth right now, but which would result in developing technologies necessary for the Large Scale Colonization Ship. I've posted elsewhere some of the ideas.

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#17 2022-06-23 20:06:59

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,674

Re: Large Ship Finance

Cost for mars comes down to the army of personnel to build the ships required to build on orbit the ship you desire to do the transporting to mars. Going big may mean huge delays in actually being able to go at all. We also know that sending the preloading of equipment and items for humans to make use of once man does go is just as daunting for the rockets and for the costs to do so.

I am wondering if technology sections of the ship can yield spin off development that would allow for targeted financing.

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#18 2022-06-24 06:46:12

kbd512
Administrator
Registered: 2015-01-02
Posts: 5,693

Re: Large Ship Finance

SpaceNut,

The large ship concept is forward-thinking.  The large ship concept is not a replacement for Starship.  Both technologies are complementary, meaning each does something so much better than the other that there's merit to investment in both.  We can't colonize other planets in a practical manner using the upper stages of rockets, nor can ships the size of the ISS land on other planets.  I didn't "decide" that the universe would or should operate this way, basic physics did.

Starship has to meet design requirements for an upper stage of a rocket that's also capable of vertical take-off and landing.  It will always be sub-optimal for in-space transport for that reason.  The large ship is an object sent into space once per vehicle lifetime, much like the ISS, which has proven to last for at least 20 years using weaker materials like 2219 Aluminum alloys.  After construction, a large ship stays in space, no different than the ISS.

The dry mass of the Starship upper stage falls between 150t and 200t.  My ship concept is only about 50t heavier than a Starship in terms of total dry mass, yet it also carries about twice the payload mass of a Starship.  250t of food / water / air plus 50t for the colonists and their personal effects.  In theory, you could send a Starship to orbit and then retrofit the AG components to create the sort of ship I had in mind.  It's not going to land anywhere afterwards, because it can't.

In terms of total mass for a round trip to Mars, my ship concept is equivalent to the propellant load of a Starship.  It requires fewer flights to restock / refuel than the propellant launches required to refuel a Starship in orbit to send it to Mars.  Over enough flights, that becomes drastically less expensive to operate than a much larger fleet of Starships.  Ultimately, the food to travel to Mars will be produced in orbit or on Mars, the Oxygen will come from lunar regolith or Mars, and the water will also be sourced from the moon or Mars.  At that point, the cost of  the consumables is borne by the Mars colony or lunar base, not people living on Earth.

As our closed-loop life support slowly but surely increases air and water recycling efficiency to near 100%, eventually the only Starship flights required to go to Mars are the ones required to reach orbit from the surface of the Earth and the one required to take you from Mars orbit to the surface of Mars.  It's not feasible to get much more efficient than that.  Right now, we're stuck with ye olde "chicken-and-egg" conundrum.  It's too expensive to colonize Mars because nobody has built out the infrastructure to make it more affordable, and therefore the infrastructure hasn't been built so nobody can afford to go.  That situation won't change itself.  A miracle is not going to happen.  It's never going to get any cheaper to fly into space, never mind go anywhere after you get into space, using the technology we're already using.  Airline ticket prices have only gone up over time as the jets and jet fuel become more expensive.  Wages have also risen to the point where an ever-greater number of people can afford to fly once per year on their own dime.  For that end result to occur, major investments into the airports and aircraft and academia was required first.  Jet aircraft made flying affordable for the masses by making it feasible to stuff more butts into seats, per aircraft, and to complete more flights per aircraft per day, than their piston-powered equivalents.

I sized my large ship concept based upon the maximum number of colonists a single Starship could reasonably take to orbit.  To achieve even greater efficiency, you need a bigger conventional rocket.  I don't know how to stuff more butts into seats using SpaceX's existing Starship design, in a practical manner.  It's technically feasible to cram more people inside, but doing so would also put them in greater danger for little to no practical benefit.  I don't want to explain to the parents of 750 to 1,000 young people that all of their children died so that we could charge $2,000 vs $4,000 for the flight.  At a certain point, being "just a little" cheaper doesn't pay off over time.

The argument over financing here seems to boil down to, "We really like our propeller-driven aircraft and don't want to consider jet engines because that sort of stuff is new and unknown."  My response to that sort of thinking is, "Well then, I guess you just resigned yourselves to never putting enough butts in seats for this entire endeavor to become truly affordable to the sorts of people who might want to go to Mars and who could reasonably contribute significantly to the construction effort."  Mars won't be colonized by a bunch of wealthy senior citizens until a bunch of much younger folks first build out the infrastructure to give those 1%ers a comfortable place to retire.

So, yeah, jet engines were a bit of a gamble when they were first developed.  The first examples had exceptionally short service lives, there were horrendous accidents, and lots of misakes were made.  The majority of the first jet engines lived to a ripe old service life age of 50 hours, unless they exploded from manufacturing defects before then.  They were totally trashed at that point and had to be completely replaced with brand new engines.  Now we have jet engines that live for 40,000 hours and complete the equivalent of 35+ trips to the moon and back.  It's so rare these days for a jet engine to fail that whenever they do, it makes the news, lots of questions get asked, and we make sure that whatever caused it to fail doesn't happen again.

These days, chemical rocket engines are, after performance is considered, almost as reliable as jet engines.  The high-stress parts are based on the same technology set, for the most part, even if more exotic fuels and oxidizers are used.  They require a lot more maintenance and inspections, but then so do NHRA nitro-methane engines.  There was a time when people went to the track to watch the nitro-fueled cars go ka-boom!  Now it's more rare to see an explosion at the track than a driver error of some kind.  The professional racing teams, and even many of the Saturday night street fighters, have figured out what works over time.

Well, guess what?

The same is now true of electric propulsion.  It's been around since the Apollo era, so it shouldn't surprise anyone that 5 decades later, when the physical principles are carefully applied and the engines are exhaustively tested, that the end result is a boringly reliable propulsion system.  It doesn't produce a spectacular fireworks show the way chemical propulsion does, but over time the fuel efficiency differences are truly stunning.

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