Arcologies - Saviors or Follies?

The idea of arcologies has always been heralded as a cure for all the problems  of modern, urbanised societies.  More than half of the world's population is now living in cities, so we would expect them to be popping up all around us, with their promised benefits of clean, renewable and sustainable living - but as of 2012 there is still not a single real arcology in existence.  The few half-built examples are all stagnating for one reason or another: the experimental Arcosanti project set in Arizona was started all the way back in 1970 by architect Paolo Soleri but is still not "ready" 42 years later; Masdar City in UAE has had its completion date put back from 2016 to 2025, a big slip in project time; Crystal Island in Russia has been postponed indefinitely citing "global economic crisis" as the reason - the name alone reminds me of the British Crystal Palace that ended in disaster.  Many more can be added to this list and their common denominator is that they all seem to be going nowhere.  Not exactly bright beacons for the future.

The reason that arcologies have a hard time working is three fold; most people don't want to live in what is essentially a massive condo built for half a million people; neither does any company of government have enough money to spend on such massive projects when the benefits are largely unproven (the neo-cities in China use proven and relatively "low-tech" layouts, architecture and town planning concepts that equate to a much lower per inhabitant cost); and finally there is a large variety in what one set of people understand as the concept and purpose of an arcology is.  This post is not dealing with "exotic arcologies" such as space habitats or ocean-faring arcologies - the scope here is practical, necessary and possible methods to create sustainable, scalable and comfortable new population centers.  Whenever you have an unclear mission brief, you will struggle to get the project off the ground.

Looks great - but what if you lived right at the bottom where the sun don't shine?

Arcologies were originally envisaged as megastructures that would be totally self sufficient in every way; power, food, water, sanitation etc.  The idea to make them big and tall is to maximise the population density in relation to geographic footprint.  This is an error; the world has  limited resources not overall land area.  Concentrating populations makes access to available resources harder as they are depleted faster in the local area.  It is better to build in areas with a surplus - using green energy generation and adequate recycling facilities for the given population size can then maintain a sustainable and comfortable living environment.  Population from overpopulated areas can then be attracted to reduce the pressure on the old urban centres.  Minimising the area for building means it is harder to adequately generate enough energy (think of the land needed to build sufficient wind or solar energy farms) or recycle waste effectively, making megastructures counterproductive. 

The theory is that arcologies are designed with commercial, habitat and industrial zones in proportions so that all inhabitants would be able to work and spend all leisure time in the arcology without the need to venture outside.  Now, this is not only impractical on certain levels (would every arcology really need to have a Large Hadron Collider / high energy particle lab?) but also this sounds too much like a prison to me.  While squeezing people together would theoretically lower commuting and the associated pollution, this is not as simple in practise.  Town planning already looks to minimise commuting and have optimal levels of habitable and commercial zones but in the real world, micro and macro economic factors make this impossible to predict accurately.  When building a $50 billion structure you hope that you could be less exposed to such risks.

This means that some of the underlying concepts of an arcology can be incongruous to our modern lifestyles.  They are meant to reduce travel to work by bringing work closer to habitation zones, but this becomes non-sensical in an age of multinational, multi-office corporations where people cannot live next to their job.  And while reducing the reliance on cars by bringing work closer to your home makes sense, many people already can cycle to work in large cities - they choose not to for reasons other than the actual distance to work being too large (for example, they might often just be too lazy...)

Large commerce buildings interspersed with rapid-transit routes and
low-rise zones and planned green areas.  Each "cell" is mostly self
sufficient but matrixed to meet any deficits in space or energy.

Arcologies of the megastucture kind are akin to the claustraphobic and titular "Caves of Steel" described by Isaac Asimov in his Robot Series; which is a bad thing, as they were largely a cautionary tale.  They are also very hard to incorporate into the current geography and economy - finding 1 million tenants and $50 billion in funding is harder than finding 10,000 tenants and $500 million. 

Smaller scale structures can be inserted into the ecosystem more easily and incorporated into or near current urban areas.  Within these smaller developments, keeping the layout compact where possible (e.g. commercial and industrial zones) but expanding to give larger green, leisure and habitat zones would increase the wellbeing of inhabitants and allowing recycling initiatives to be efficient and give close to zero pollution footprint.  Even a cursory glance at these two approaches draws an easy comparison as to which is more appealing.

Where would you purchase a property?

As mentioned, a staple of Sci Fi, mega-structure arcologies tend to become run-down and corrupt while smaller "cell structure" arcologies are usually seen in idyllic settings with happy populations.  Acting as a "cell structure", small arcologies can be pieced together, each tending to its own energy and recycling but catering for small local variations in demand for certain zone types by allowing limited commuting and "leasing" of resources.  This can be thought of as the expansion of the current concept of "green homes"; where a home produces and recycles much of its own energy and waste.  Taking this to a larger level allows for economies of scale and public funding to make this more efficient.  An inflexion point can be imagined where the increasing the scale of the arcology no longer produces big gains in efficiency while the undesirable symptoms of the mega-structure design emerge.

A design attached to a larger, existing population hub.  Though providing extra functional space for the city it will increase population density as there is no added leisure or green space.

Small or large, these projects are mostly theory right now.  As recycling and renewable energy technologies improve, populations continue to grow and we become more serious about the "green agenda", the likelihood will increase that we take the idea of arcologies seriously and secure the necessary funding to make them happen.  When that happens, it would be interesting if a planned and considered approach is taken to build the smaller scale "cellular" units or if there still will be the belief that monstrous, monolithic mega-structures are chosen.