World population will be around 15-25 billion in 2100 and will increase through 2200 because of African fertility, life extension and other technology

The United Nations (UN) recently released population projections based on data until 2012 and a Bayesian probabilistic methodology. Analysis of these data reveals that, contrary to previous literature, the world population is unlikely to stop growing this century. There is an 80% probability that world population, now 7.2 billion people, will increase to between 9.6 billion and 12.3 billion in 2100. This uncertainty is much smaller than the range from the traditional UN high and low variants. Much of the increase is expected to happen in Africa, in part due to higher fertility rates and a recent slowdown in the pace of fertility decline. Also, the ratio of working-age people to older people is likely to decline substantially in all countries, even those that currently have young populations.

There is only a 30% chance of population peaking by 2100. This is even without considering radical life extension or any other turnaround in human fertility.

African fertility alone means world population will not peak by 2100. The old world population forecast will flatten at 9-10 billion before 2100 is done and wrong

Here I describe how the world of 2100 and 2200 will have a lot more people, efficient urbanization in megacities with robotic cars and turbolifts and easy access to space and substantial colonization. Energy and food will not be constraints.

I think 2100 will see a population around 20 billion and 2200 a population in the solar system in the 40-80 billion range.

What could boost population growth ?

* radical life extension for fewer deaths
* lower cost and more effective in vitro fertilization. About 16-20% of couples who want children cannot have them
* if technology in the post-2050 timeframe delivers cheap access to space (orbit and solar system), material abundance from nanotechnology and other technology and abundant energy from nuclear fusion, molten salt fission, advanced solar power and space based solar power, then there could be population and wealth growth without adverse impacts even if population increased hundreds of times beyond current levels

if Africa’s birthrate stayed at current levels and did not drop at all then world population would be about 20-25 billion in 2100.

The extreme longevity scenarios could add 1 billion, 3 billion or 6 billion people to projections.
1 billion would be the difference between the 2010 and 2012 African fertility adjustment.
3 billion would be the difference between 2000 and 2015 African fertility adjustments.
6 billion would be like a worldwide fertility increase of about 0.5 children per couple.

Later in this article I discuss how we can scale food production.

I have also previously looked at scaling nuclear power.

Deep burn nuclear power options –
* fast neutron breeder reactors with onsite or offsite reprocessing of fuel can close the fuel cycle and eliminate nuclear waste (unburned fuel)
* molten salt reactors (like Terrestrial Energy) can increase the power derived from existing uranium by six times

Various reactors from China and Terrestrial Energy and others can be factory mass produced.

Nanotechnology and nuclear fusion would deliver space planes that could easily move people around the solar system the way 20,000 commercial jets move hundreds of million of people around the world now. Colonization of space in orbit, planets or asteroids would become trivial.

Even more mundane technology will open up space and colonization
* Spacex reusable rockets seem likely within a couple of years
* Bigelow Aerospace can make affordable inflatable space stations
* Spiderfab robotic assembly can make large structures in space

Efficient and clean megacities will be possible on earth
* China will build high speed rail to connect cities all across Asia, Europe and South America
* robotic cars will be able to increase the size and speed of movement within cities without traffic jams
* factory built skyscrapers with cable less multidirection elevators will move people easily within supertall buildings and between buildings
* follow on devices to Segway will enable people to have lightweight electrical enhanced movement

There was a NASA analysis of a minimized technological approach towards human self sufficiency off earth. We can now look at building up from the basic level with likely new space capabilities Spacex Heavy launches with some level of reusability, Bigelow expandable space stations and Spiderfab.

We should use Spiderfab (robotic assembly in space) to build the 2000 meter long channel between space station compartments. This will allow slow rotations to provide centrifugal force as a replacement for gravity.

Bigelow modules would need to be enhanced with an outer layer which could hold water. Ideally water would be obtained from the moon or asteroids for large numbers of habitats.

Emphasis needs to be placed on in situ manufacturing, using and developing resources in space, production of photo voltaic power, and production of food to enable the more self-sufficient off Earth settlement – “extending human presence across the solar system.”

A Bigelow space module, spiderfab enhanced and Spacex launched version of a ten thousand person space station possible by 2030

A ten thousand person colonization space ship design is proposed with a focus on how the community and living spaces should be designed. People are assigned area with the density of the city of Seattle and standard mixed use living areas. Everyone has 50 square meters of living space. There is agricultural and other green areas.

Get big bases in orbit and on the moon and have a more powerful bootstrap to massive space industrialization

Massive and complete automation could enable industrializtion of the moon and space. By using some larger human colonies along with the robots then it would be more robust and less dependent on perfect automation.

Advances in robotics and additive manufacturing have become game-changing for the prospects of space industry. It has become feasible to bootstrap a self-sustaining, self-expanding industry at reasonably low cost. Simple modeling was developed to identify the main parameters of successful bootstrapping. This indicates that bootstrapping can be achieved with as little as 12 metric tons (MT) landed on the Moon during a period of about 20 years. The equipment will be teleoperated and then transitioned to full autonomy so the industry can spread to the asteroid belt and beyond. The strategy begins with a sub-replicating system and evolves it toward full self-sustainability (full closure) via an in situ technology spiral. The industry grows exponentially due to the free real estate, energy, and material resources of space. The mass of industrial assets at the end of bootstrapping will be 156 MT with 60 humanoid robots, or as high as 40,000MT with as many as 100,000 humanoid robots if faster manufacturing is supported by launching a total of 41 MT to the Moon. Within another few decades with no further investment, it can have millions of times the industrial capacity of the United States. Modeling over wide parameter ranges indicates this is reasonable, but further analysis is needed. This industry promises to revolutionize the human condition.

Spiderfab can reduce costs by ten times or more and enable vastly larger structure in space. Larger structures such multi-kilometer solar sails, antennas or mirrors can transform space capabilities.

In March, 2014, NASA awarded Tethers Unlimited, Inc. (TUI) a $750,000 contract to continue development of its “Trusselator” technology. The Trusselator is a device for in-­space additive manufacture of high-­performance truss structures for systems such as large solar arrays and antennas.

Tethers Unlimited is developing a set of technologies called SpiderFab™ to enable on-­orbit fabrication of spacecraft components. The SpiderFab architecture integrates elements of 3D printing, automated composite layup, and robotic assembly to create large, light-weight structures. The SpiderFab robotic systems will integrate these structures with solar cells, reflectors, and other elements to create football-­stadium sized antennas, multi-­hundred kilowatt solar arrays, and other large components for space systems.

NASA has given a phase 2 NIAC contract to Tethers Unlimited. The NIAC contract is for developing techniques to enable robotic systems to assemble these trusses into larger structures, such as antenna dishes and solar arrays

Technical Abstract

The Trusselator technology will enable on-orbit fabrication of support structures for high-power solar arrays and large antennas, achieving order-of-magnitude improvements in packing efficiency and launch mass while reducing life-cycle cost. The Phase I Trusselator effort successfully demonstrated fabrication of continuous lengths of high-performance carbon fiber truss using a novel additive manufacturing process, establishing the technology at TRL-4. The initial truss samples displayed bending stiffness efficiency superior to SOA deployable mast technologies. The Phase II effort will address the key technical risks and mature the Trusselator technology to TRL-6. We will do so by first refining the additive manufacturing process elements to improve process reliability and increase structural performance of the truss products. We will then design and prototype a Trusselator capable of operation in the thermal-vacuum environment of space, incorporating design improvements to reduce weight and stowed volume. Demonstration of fabrication of multi-meter lengths of truss in a vacuum environment will establish the technology at TRL-6. We will also develop an automated process for integrating the fabricated truss with thin-film solar cell blankets, and demonstrate this process with a solar cell blanket simulator. These Phase II efforts will prepare the Trusselator for flight demonstration in Phase III efforts to enable its adoption into the critical path for flight missions requiring high-power solar arrays.

Potential NASA Commercial Applications

The Trusselator is a key element of the NIAC “SpiderFab” architecture for on-orbit fabrication and integration of space systems. This technology will enable order-of-magnitude improvements in performance-per-cost for a wide range of mission, including:

* High Power Solar Arrays for SEP Exploration Missions
* Multi-Hundred-Meter Solar Sails for Outer Planet Missions
* Arecibo-scale Antennas for High-Bandwidth Communications with Mars and Deep-Space Missions
* Kilometer-Scale Masts for Long-Baseline Interferometric Astronomy
* Kilometer-Scale Sparse Apertures for Exoplanet Imaging

Potential Non-NASA Applications
The Trusselator will also enable on-orbit fabrication of large apertures and baselines for DoD space systems to enable order-of-magnitude improvements in bandwidth, sensitivity, resolution, and power for a wide range of tactical, strategic, and national security missions, including SATCOM, geolocation, SIGINT, and Earth observation. It will also enable affordable construction of large antennas for GEO commercial communications satellites.

2. Spacex will attempt to land the first stage of Falcon 9 on December 9th, 2014. Being able to land and reuse rocket boosters can reduce the costs for launching into space by ten to one hundred times.

3. The first launch of the Falcon Heavy should be in 2015.

As of March 2013, Falcon 9 v1.1 launch prices are $4,109 per kilogram ($1,864/lb) to low-Earth orbit when the launch vehicle is transporting its maximum cargo weight.

As of March 2013, Falcon Heavy launch prices are below $1,000 per pound ($2,200/kg) to low-Earth orbit when the launch vehicle is transporting its maximum delivered cargo weight. SpaceX has claimed the cost of reaching low Earth orbit can be as low as US$1,000 per pound if an annual rate of four launches can be sustained, and as of 2011 planned to eventually launch 10 Falcon Heavy and 10 Falcon 9 annually.

The first commercial launch of a Falcon Heavy is targeted for 2017.

4. Spacex is developing the methane Raptor engine.

This would enable monster rockets and would likely be the BFR (Big F**ing Rocket) or Mars Colony Transport. Elon Musk has discussed getting the cost of space launch without reuse down to $500 per pound with a large rocket.

Exoscientist Robert Clark has calculated a 15 Raptor engine Spacex rocket could enable abut 500 tons of payload in a single launch.

A June 2014 talk by Tom Mueller, the head of rocket engine development at SpaceX, provided more specific engine performance target specifications indicating 6,900 kN (705 tonnes-force) of sea-level thrust, 8,200 kN (840 tonnes-force) of vacuum thrust, and a specific impulse of 380 seconds.

The Spacex Falcon heavy has three cores and has nine engines on each core as seen in this picture from the site. Having five engines per core would show about three engines in profile on each core.

Pictures of the Falcon Heavy engines from Spacex.

In April 2014, SpaceX completed the requisite upgrades and maintenance to the Stennis test stand to prepare for testing of Raptor components, and expected to begin tests at the facility prior to the end of May 2014.

The Raptor engine will be powered by liquid methane and liquid oxygen using a more efficient staged combustion cycle, a departure from the ‘open cycle’ gas generator system and lox/kerosene propellants that current Merlin engines use. The Space Shuttle Main Engines (SSME) also used a staged combustion process, as do several Russian rocket engines.

More specifically, Raptor will utilize a “full-flow” staged combustion cycle, where 100 percent of the oxidizer—with a low-fuel ratio—will power the oxygen turbine pump, and 100 percent of the fuel—with a low-oxygen ratio—will power the methane turbine pump. Both streams—oxidizer and fuel—will be completely in the gas phase before they enter the combustion chamber. Prior to 2014, only two full-flow staged combustion rocket engines have ever progressed sufficiently to be tested on test stands: the Soviet RD-270 project in the 1960s and the Aerojet Rocketdyne Integrated powerhead demonstration project in the mid-2000s.

Raptor is being designed to produce 8,200 kN (1,800,000 lbf) of vacuum thrust—6,900 kN (1,600,000 lbf) thrust at lift-off—with a vacuum Isp of 380 seconds and a sea-level Isp of 321 seconds. Final thrust and Isp specifications for the as-built engines are expected to be refined as SpaceX moves the engine through the multi-year development cycle.

Additional characteristics of the full-flow design that are projected to further increase performance or reliability include:

* eliminating the fuel-oxidizer turbine interseal, which is a potential point of failure in more traditional engine designs
* lower pressures are required through the pumping system, increasing life span and further reducing risk of catastrophic failure
* ability to increase the combustion chamber pressure, thereby either increasing overall performance, or “by using cooler gases, providing the same performance as a standard staged combustion engine but with much less stress on materials, thus significantly reducing material fatigue or [engine] weight.”

5. An orbital propellant depot is a cache of propellant that is placed in orbit around Earth or another body to allow spacecraft or the transfer stage of the spacecraft to be fueled in space. It is one type of space resource depots that have been proposed for enabling infrastructure-based exploration

Intelsat has recently contracted for an initial demonstration mission to refuel several satellites in geosynchronous orbit, beginning in 2015.

NASA had plans to mature techniques for enabling and enhancing space flights that use propellant depots in the “CRYOGENIC Propellant STorage And Transfer (CRYOSTAT) Mission”. The CRYOSTAT vehicle was expected to be launched to LEO in 2015.

Cryostat does not appear to be in the 2015 NASA budget summary.

The CRYOSTAT architecture comprises technologies in the following categories:

Storage of Cryogenic Propellants
Cryogenic Fluid Transfer
Automated Rendezvous and Docking (AR&D)
Cryogenic Based Propulsion

Turbolift elevators, robotic cars and factory built skyscrapers

ThyssenKrupp places linear motors in elevator cabins, transforming conventional elevator transportation in vertical metro systems. MULTI elevator technology increases transport capacities and efficiency while reducing the elevator footprint and peak loads from the power supply in buildings. Several cabins in the same shaft moving vertically and horizontally will permit buildings to adopt different heights, shapes, and purposes. The first MULTI unit will be in tests by 2016.

MULTI will transform how people move inside buildings, just as the recently introduced ThyssenKrupp’s ACCEL, which also applies the same linear motor technology, is set to transform mobility between short distances in cities and airports.

In a manner similar to a metro system operation, the MULTI design can incorporate various self-propelled elevator cabins per shaft running in a loop, increasing the shaft transport capacity by up to 50% making it possible to reduce the elevator footprint in buildings by as much as 50%.

Using no cables at all, a multi-level brake system, and inductive power transfers from shaft to cabin, MULTI requires smaller shafts than conventional elevators, and can increase a building’s usable area by up to 25%, considering that, depending on the size of the building, current elevator-escalator footprints can occupy up to 40% of the building’s floor space. The overall increase in efficiency also translates into a lower requirement for escalators and additional elevator shafts, resulting in significant construction cost savings as well as a multiplication of rent revenues from increased usable space.

ThyssenKrupp’s MULTI consists of various cabs per shaft and enables vertical and horizontal movement.

The significant extra space available is only one of MULTI’s advantages. Although the ideal building height for MULTI installations starts at 300 metres, this system is not constrained by a building’s height. Building design will no longer be limited by the height or vertical alignment of elevator shafts, opening possibilities to architects and building developers they have never imagined possible.

MULTI is based on the concept of ThyssenKrupp TWIN’s control system and safety features, but includes new features such as new and lightweight materials for cabins and doors, resulting in a 50% weight reduction as compared to standard elevators, as well as a new linear drive – using one motor for horizontal and vertical movements.

Commenting on this momentous breakthrough in the company’s history of innovations at the global headquarters of ThyssenKrupp in Essen, Germany, Andreas Schierenbeck, CEO of ThyssenKrupp Elevator AG said, “As the nature of building constructions evolve, it is also necessary to adapt elevator systems to better suit the requirements of buildings and high volumes of passengers. From the one dimensional vertical arrangement to a two dimensional horizontal/vertical arrangement with more than one or two cabins operating in each shaft, MULTI represents a proud moment in ThyssenKrupp’s history of presenting cutting-edge transport technologies that best serve current mobility needs”.

Operating on the basic premise of a circular system, such as a paternoster, MULTI consists of various cabins running in a loop at a targeted speed of 5 m/s, enabling passengers to have near-constant access to an elevator cabin every 15 to 30 seconds, with a transfer stop every 50 metres.

Schierenbeck said, “Per year, New York City office workers spend a cumulative amount of 16.6 years waiting for elevators, and 5.9 years in the elevators. This data provides how imperative it is to increase the availability of elevators.”

A 2013 analysis of two-dimensional elevator traffic systems likens the present use of one cabin per elevator shaft to using an entire railway line between two cites to operate a single train – clearly a waste of resources. By combining groundbreaking technology with a simple operation concept and convenience of passenger use, ThyssenKrupp’s MULTI will transform the idea of a flexible number of cars per shaft from a distant vision for the future into a reality.

“To get this groundbreaking product onto the market our new test tower in Rottweil, Germany, provides the perfect test and certification environment. The tower is set to be completed at the end of 2016, and by this time, we aim to have a running prototype of MULTI”, Schierenbeck adds.

Efficient Urbanization and greater wealth

Sky City Skyscrapers (200-300 stories) and robotic cars (4 times the density of road traffic) will make certain megacities (future New York, Shanghai, Tokyo etc…) one third to one half of the overall world population and they would have 75% more GDP per capita than they do today. There would be rural, regular urban then super-urban. Research shows that doubling population and increased urban density boosts productivity by about 15%.

Serious study of the role of location and density in economic development probably owes its origins to Alfred
Marshall’s work on location and economic development in the early 1900s. Cities are economic drivers – the very core of economic growth and development. Higher earnings paid to urban workers and premiums paid by firms to be in urban areas are evidence of cities’ productive advantages. In the US, for example, earnings in cities are around 33% more than those in non urban areas (Glaeser and Mare, 2001). Even within Greater London, the urban premium is high: the average earnings for a worker in inner London (£49,400) was nearly double that of the average for outer London workers (£26,700) in 2007.

The ways in which density is linked to productivity has been developed in a wide array of research projects. Six key impacts are discussed in this section:
* density allows a higher degree of specialisation, increasing efficiency;
* reduced transport time and costs for products/goods/services from one stage to the next, or from producer to consumer, occurs in denser areas if the transport infrastructure is sufficient;
* increased density increases the prevalence of knowledge spillovers, increasing innovation
* density allows firms to have access to larger markets of suppliers (especially labour supply) and consumers, allowing competition to enhance the quality of inputs and outputs;
* efficiencies of scale are created in denser markets where suppliers are reaching more potential customers;
* reduced land take in denser areas allows more economic activity to take place on a fixed piece of land than less dense designs;

In addition to understanding the nature of the linkages between density and productivity, economic research estimates the scale of these linkages.

Seminal work by Ciccone and Hall (1996) assessed the impacts of density on productivity in the US, and found that doubling employment density, and keeping all other factors constant, increased average labour productivity by around 6%. Subsequent work by Ciccone (1999) found that in Europe, all other things being equal, doubling employment density increased productivity by 5%. A third paper (Harris and Ioannides, 2000) applies the logic directly to metropolitan areas and also finds a 6% increase in productivity with a doubling of density.

More recent work by Dan Graham (2005b, 2006) examines the relationship between increased effective density (which takes into account time travelled between business units) and increased productivity across different industries. Graham finds that across the whole economy, the urbanisation elasticity (that is, the response of productivity to changes in density) is 0.125. This means that a 10% increase in effective density, holding all other factors constant, is associated with a 1.25% increase in productivity for firms in that area. Doubling the density of an area would result in a 12.5% increase in productivity.

Economist Robin Hanson noted that doubling the population of any city requires only about an 85% increase in infrastructure, whether that be total road surface, length of electrical cables, water pipes or number of petrol stations. This systematic 15% savings happens because, in general, creating and operating the same infrastructure at higher densities is more efficient, more economically viable, and often leads to higher-quality services and solutions that are impossible in smaller places. Interestingly, there are similar savings in carbon footprints — most large, developed cities are ‘greener’ than their national average in terms of per capita carbon emission.

Google told the world it has developed computer driving tech that is basically within reach of doubling (or more) the capacity of a road lane to pass cars. Pundits don’t seem to realize just how big a deal this is – it could let cities be roughly twice as big, all else equal.

Factory mass produced Sky City will become the tallest building in the world and more importantly will impact urbanization in the developing world. Successful urbanization will lift people up to higher levels of per capita income, increase productivity and can reduce pollution.

I see the impact of Sky Cities and Broad Factory mass produced skyscrapers like the move from 3 to 4 story buildings to cities with 30 story buildings. Average skyscrapers are now 30 to 50 stories tall. This factory mass production will make 100 to 300 story buildings affordable and common.

Eight times the density would be a 45% boost to productivity.

Road capacity could be boosted by 4 times using robotic cars. This could be another 30% boost to productivity.

The Sky Cities are also designed to reduce pollution (99% less construction dust) and use 5 times less material than a regular skyscraper. They would also house homes, offices and stores which will enable more in building commuting. This will boost productivity and reduce commuting times.

Certain megacities (future New York, Shanghai, Tokyo etc…) could increase to being about one third to one half of the overall population and could have 75% more GDP per capita than they do today. There would be rural, regular urban then super-urban.