Space elevator economics compares the cost of sending a payload into Earth orbit via a

space elevator A space elevator, also referred to as a space bridge, star ladder, and orbital lift, is a proposed type of planet-to-space transportation system, often depicted in science fiction. The main component would be a cable (also called a tether) an ...

with the cost of doing so with alternatives, like

rocket A rocket (from it, rocchetto, , bobbin/spool) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entire ...

Costs of current systems (rockets)

The costs of using a well-tested system to launch

payload Payload is the object or the entity which is being carried by an aircraft or launch vehicle. Sometimes payload also refers to the carrying capacity of an aircraft or launch vehicle, usually measured in terms of weight. Depending on the nature of ...

s are high. The main cost comes from the components of the launch system that are not intended to be reused, which normally burn up in the atmosphere or are sent to

graveyard orbit A graveyard orbit, also called a junk orbit or disposal orbit, is an orbit that lies away from common operational orbits. One significant graveyard orbit is a supersynchronous orbit well beyond geosynchronous orbit. Some satellites are moved int ...

s. Even when reusing components, there is often a high refurbishment cost. For

geostationary transfer orbit A geosynchronous transfer orbit or geostationary transfer orbit (GTO) is a type of geocentric orbit. Satellites that are destined for geosynchronous (GSO) or geostationary orbit (GEO) are (almost) always put into a GTO as an intermediate step f ...

s, prices are as low as about

US$ The United States dollar (symbol: $; code: USD; also abbreviated US$ or U.S. Dollar, to distinguish it from other dollar-denominated currencies; referred to as the dollar, U.S. dollar, American dollar, or colloquially buck) is the official ...

11,300/kg for a

Falcon Heavy Falcon Heavy is a partially reusable heavy-lift launch vehicle that is produced by SpaceX, an American aerospace manufacturer. The rocket consists of two strap-on boosters made from Falcon 9 first stages, a center core also made from a Falc ...

Falcon 9 Falcon 9 is a partially reusable medium lift launch vehicle that can carry cargo and crew into Earth orbit, produced by American aerospace company SpaceX. The rocket has two stages. The first (booster) stage carries the second stage and pa ...

launch. Costs of

low Earth orbit A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never m ...

launches are significantly less, but this is not the intended orbit for a space elevator.

Proposed cost reductions

Various adaptations of the conventional rocket design have been proposed to reduce the cost. Several are currently in development, like the

SpaceX Starship Starship is a Fully-reusable orbital launch vehicle, fully reusable, super heavy-lift launch vehicle under development by SpaceX, an American aerospace company. With more than twice the thrust of the Saturn V, it is designed to be the most powe ...

. An aspirational price for this fully reusable launch vehicle is $10/kg, significantly cheaper than most proposed space elevators.

New Glenn New Glenn is a heavy-lift orbital launch vehicle in development by Blue Origin. Named after NASA astronaut John Glenn, design work on the vehicle began in 2012. Illustrations of the vehicle, and the high-level specifications, were initially ...

is also currently in development, a partially reusable rocket that promises to reduce price. However, an exact cost per launch has not been specified. Others, like the

Sea Dragon Sea Dragon or seadragon may refer to: Fish * Leafy seadragon (''Phycodurus eques'') * '' Phyllopteryx'' genus ** Common seadragon or weedy seadragon (''Phyllopteryx taeniolatus'') ** Ruby seadragon (''Phyllopteryx dewysea'') Military * Operat ...

and

Roton In theoretical physics, a roton is an elementary excitation, or quasiparticle, seen in superfluid helium-4 and Bose–Einstein condensates with long-range dipolar interactions or spin-orbit coupling. The dispersion relation of elementary excita ...

have failed to get sufficient funding. The

Space Shuttle The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program na ...

promised a large cost reduction, but financially underperformed due to the extensive refurbishment costs needed after every launch.

Cost estimates for a space elevator

For a space elevator, the cost varies according to the design.

Bradley C. Edwards Bradley C. Edwards is an American physicist who has been involved in the development of the space elevator concept. Biography Dr Edwards received his PhD degree in Physics from the University of Wisconsin–Madison in 1990. His thesis work wa ...

received funding from NIAC from 2001 to 2003 to write a paper, describing a space elevator design. In it he stated that: "The first space elevator would reduce lift costs immediately to $100 per pound" ($220/kg). The

gravitational potential energy Gravitational energy or gravitational potential energy is the potential energy a massive object has in relation to another massive object due to gravity. It is the potential energy associated with the gravitational field, which is released (conv ...

of any object in geosynchronous orbit (GEO), relative to Earth's surface, is about 50 MJ (15 kWh) of energy per

kilogram The kilogram (also kilogramme) is the unit of mass in the International System of Units (SI), having the unit symbol kg. It is a widely used measure in science, engineering and commerce worldwide, and is often simply called a kilo colloquially ...

(see

geosynchronous orbit A geosynchronous orbit (sometimes abbreviated GSO) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day). The synchronization of rotation and orbit ...

for details). Using wholesale electricity prices for 2008 to 2009, and the current 0.5% efficiency of

power beaming Wireless power transfer (WPT), wireless power transmission, wireless energy transmission (WET), or electromagnetic power transfer is the transmission of electrical energy without wires as a physical link. In a wireless power transmission system, ...

, a space elevator would require US$220/kg just in electrical costs. Dr. Edwards expects technical advances to increase the efficiency to 2%. However, due to the fact that space elevators would have a limited throughput as only a few payloads could climb the tether at any one time, the launch price may be subject to market forces.

Funding of capital costs

According to a paper presented at the 55th International Astronautical Congress in

Vancouver Vancouver ( ) is a major city in western Canada, located in the Lower Mainland region of British Columbia. As the most populous city in the province, the 2021 Canadian census recorded 662,248 people in the city, up from 631,486 in 2016. Th ...

in October 2004, the

can be considered a prestige

megaproject A megaproject is an extremely large-scale investment project. According to the ''Oxford Handbook of Megaproject Management'', "Megaprojects are large-scale, complex ventures that typically cost $1 billion or more, take many years to develop and ...

whose current estimated cost (US$6.2 billion) is favourable compared to other megaprojects e.g. bridges, pipelines, tunnels, tall towers, high-speed rail links and maglevs. Costs are also favourable compared to that of other aerospace systems and launch vehicles.

Total cost of a privately funded Edwards' Space Elevator

A space elevator built according to the Edwards proposal is estimated to cost $6 billion. For comparison, in potentially the same time frame as the elevator: * the

Skylon Skylon may refer to: * Skylon (Festival of Britain), a landmark structure of the 1951 Festival of Britain * Skylon (spacecraft), a proposed orbital spaceplane * Skylon Tower The Skylon Tower, in Niagara Falls, Ontario, is an observation tower t ...

, a 12,000 kg cargo capacity single-stage-to-orbit spaceplane (not a conventional rocket) is estimated to have an R&D and production cost of about $15 billion. The vehicle has about $3,000/kg price tag. Skylon would be suitable to launch cargo ''and particularly'' people to low/medium Earth orbit (targeting maximum 30 people per flight). Early space elevator designs move only cargo but could move people as well to a much wider range of destinations. * Another alternative project to get large numbers of people and cargo to orbit inexpensively during this time frame is the

which, like Skylon, is not a conventional rocket design as it will be fully reusable. Its cargo capacity will be between , is estimated to have an R&D cost of $10 billion, and production cost of about $200-million for Starship crew, $130-million for Starship tanker and $230-million for Super Heavy. The system has a less than $140/kg price tag which is possibly as low as $47/kg. It will be capable of transporting 100 people comfortably to Mars (therefore significantly more to low/medium earth orbit).

References

{{DEFAULTSORT:Space elevator economics

Economics Economics () is the social science that studies the production, distribution, and consumption of goods and services. Economics focuses on the behaviour and interactions of economic agents and how economies work. Microeconomics analy ...