Space elevator vs reusable rockets

What has each route to orbit shown so far, and what is still missing?

The reusable rocket row rests on 1993 Space Shuttle figures, which give a planned flight rate but no flight count. No tether-scale space elevator hardware is cited. Space-based solar power is included as a cargo demand example, and its sourced tests are small and in orbit rather than grid-scale.

Space elevator vs reusable rockets. Each cell shows a value, how well it is evidenced, and its sources.
Option	Cost per kilogram to orbitUS dollars per kilogram delivered to low Earth orbit, with the year and vehicle stated. Left empty where no reliable public figure was found.	What has been demonstratedThe strongest result shown in hardware, with its setting (ground test, in orbit or operations), scale and year.	Main unsolved problemThe principal technical or economic gap named in the cited sources, in one line.
Reusable rockets	No reliable public figure	GAO (1993) reports that NASA's fixed costs were set to maintain the capability to fly the Space Shuttle eight or nine times a year. The source gives no actual flight count.Reported, unverified[1]	Fixed operations costs. NASA's figure, reported by GAO in 1993, is that fixed costs are about 90 per cent of a Shuttle flight's operations cost if the eight-or-nine-flights-a-year capability is kept. Savings from a lower flight rate are therefore limited.Reported, unverified[1]
Space elevator	No reliable public figure	2009 Power Beaming Challenge: LaserMotive's laser-powered climber ascended a 1 km cable the full distance on four occasions, at a maximum speed of 3.97 m/s. This was an Earth-based contest, not an orbital tether.Demonstrated[2]	Tether material at length. The longest carbon nanotube made is 0.5 m (IAC 2022). A 2005 NASA conference paper names carbon nanotube-reinforced composites as the most critical technology, with a ribbon target around 100 GPa.Reported, unverified[4][3]
Space-based solar power (cargo demand example)	No reliable public figure	In orbit, the 2023 MAPLE experiment on SSPD-1 transmitted power wirelessly to receivers about a foot (roughly 30 cm) away, which lit a pair of LEDs. The source does not report grid electricity.Demonstrated[5][6]	Sustained transmitted power. After stress testing, the mission account reports a drop in total transmitted power, which it attributes to degradation of a few transmitting elements in the array. The sources do not report power delivered to a grid.Demonstrated[5][6]

Space elevator vs reusable rockets. Each cell shows a value, how well it is evidenced, and its sources.

Option

Cost per kilogram to orbitUS dollars per kilogram delivered to low Earth orbit, with the year and vehicle stated. Left empty where no reliable public figure was found.

What has been demonstratedThe strongest result shown in hardware, with its setting (ground test, in orbit or operations), scale and year.

Main unsolved problemThe principal technical or economic gap named in the cited sources, in one line.

Reusable rockets

No reliable public figure

GAO (1993) reports that NASA's fixed costs were set to maintain the capability to fly the Space Shuttle eight or nine times a year. The source gives no actual flight count.Reported, unverified[1]

Fixed operations costs. NASA's figure, reported by GAO in 1993, is that fixed costs are about 90 per cent of a Shuttle flight's operations cost if the eight-or-nine-flights-a-year capability is kept. Savings from a lower flight rate are therefore limited.Reported, unverified[1]

Space elevator

No reliable public figure

2009 Power Beaming Challenge: LaserMotive's laser-powered climber ascended a 1 km cable the full distance on four occasions, at a maximum speed of 3.97 m/s. This was an Earth-based contest, not an orbital tether.Demonstrated[2]

Tether material at length. The longest carbon nanotube made is 0.5 m (IAC 2022). A 2005 NASA conference paper names carbon nanotube-reinforced composites as the most critical technology, with a ribbon target around 100 GPa.Reported, unverified[4][3]

Space-based solar power (cargo demand example)

No reliable public figure

In orbit, the 2023 MAPLE experiment on SSPD-1 transmitted power wirelessly to receivers about a foot (roughly 30 cm) away, which lit a pair of LEDs. The source does not report grid electricity.Demonstrated[5][6]

Sustained transmitted power. After stress testing, the mission account reports a drop in total transmitted power, which it attributes to degradation of a few transmitting elements in the array. The sources do not report power delivered to a grid.Demonstrated[5][6]

What the table shows

No row has a reliable public cost per kilogram to orbit in the sources checked, so the cost dimension is empty for all three.
The reusable rocket row cites 1993 Space Shuttle figures: a planned flight rate of eight or nine a year, and fixed costs of about 90 per cent of operations cost. The source gives no flight count.
The space elevator row's demonstrated result is an Earth-based climber contest over a 1 km cable, and its main gap is tether material at length.
The space-based solar power row's demonstrated result is wireless power over about a foot (roughly 30 cm) in orbit, and its reported gap is a drop in transmitted power after stress testing.

Read with care

The GAO figure of $413.5 million is the average cost per Space Shuttle flight in fiscal 1993. It excludes about $30.2 billion of development and facility spending through fiscal 1992, and future upgrade costs. It is per flight, not per kilogram, so it is not in the cost cells.
The three rows answer different questions: a launch vehicle, a transport concept and a power system with a cargo use case. Their results are not like-for-like.
The 2009 climber test ran on an Earth-based cable, and the 2023 power test ran in orbit over about 30 cm, so the proof-of-concept results are at very different scales.
The 2005 NASA paper gives its ribbon target as '1OOGPa' in the text the source page displays. The 100 GPa value is read as the intended figure and should be checked against the paper before publication.

Sources

government report
Space Transportation: The Content and Uses of Shuttle Cost Estimates (GAO/NSIAD-93-115)
U.S. General Accounting Office (copy hosted by Justia), 28 Jan 1993. Accessed 21 Oct 2026.
other
Lasers Enable Alternative Power Transmission
NASA Spinoff 2016, 2016. Accessed 21 Oct 2026.
conference paper
Critical Technologies for the Development of Future Space Elevator Systems
David V. Smitherman, Jr.. NASA Marshall Space Flight Center (IAC-05-D4.2.04), NASA NTRS, 2005. Accessed 21 Oct 2026.
conference paper
Space Elevator tether materials: An overview of the current candidates
Adrian Nixon, Dennis Wright, John Knapman. International Astronautical Federation, IAC 2022 (paper 69339), 2022. Accessed 21 Oct 2026.
university press release
In a First, Caltech's Space Solar Power Demonstrator Wirelessly Transmits Power in Space
California Institute of Technology, 1 Jun 2023. Accessed 21 Oct 2026.
university press release
Space Solar Power Project Ends First In-Space Mission with Successes and Lessons
California Institute of Technology, 16 Jan 2024. Accessed 21 Oct 2026.