First published in Cleantech magazine, September 2008. Copyright Cleantech Investor 2008.
by Anne McIvor
With over half of the global population now based in cities the challenges posed by urban living are becoming increasingly acute. Potential solutions are being forwarded by architects engineers,industrialists and city planners around the world. We review the issues and some of the potential solutions.
The challenge of urbanisation
Cities, since ancient times, have been symbols of civilisation. Ancient cities, however, were mere villages compared to the massive metropolises which we have created in the modern world.
At the start of the 20th century, only 14% of the global population lived in cities. By 2000 this proportion had grown to 47% – and this year the world’s urban population is estimated to have increased to more than 50% of all humans – or 3.3 billion people. The number of city dwellers is expected to grow to almost 5 billion by 2030, according to the United Nations Population Fund.
There are now some 20 ’megacity’ conurbations – cities with populations of more than 10 million – in the world. These include New York, Tokyo, Mexico City, Sao Paulo and Bombay. Growth in the megacities has been less than expected: medium-sized cities of 500,000 or below – where urban problems are less challenging – are the biggest growth areas. One billion people – or one-sixth of the world’s population – live in shanty towns, mainly in developing countries: not surprisingly, the provision of basic services is a challenge in these regions.
Urban living poses major difficulties. The cities of today are massive consumers of energy for numerous applications, the by-products of which are enormous volumes of pollution and waste. The ‘carbon footprint’ of a city is high on the agendas of city governors, especially those in the developed world. Emissions of gases which affect the health of the population through air pollution are a major challenge for many cities in developing countries – and remain a challenge even in the developed world.
In Europe, there is a high correlation between the areas of greatest concentration of pollutants and the areas of most concentrated industry and population mass – including the Po Valley region in Italy, the Benelux/German Ruhr Valley region and major cities such as Paris and London.
In the UK, domestic coal combustion was historically a significant source of pollution, and was the cause of the smog which frequently enveloped London and other major cities. Emissions of pollutants such as NOx from coal in the UK have declined over the years with the introduction of legislation to control the use of coal. However, there are still dangerously high levels of particulate matter (PM) in the atmosphere. The National Atmospheric Emissions Inventory lists the main sources of primary PM10 as:
Road transport
Stationary combustion
Industry
Air pollution is primarily the result of the combustion of fossil fuels. Concentrations are highest in areas which combine heavy volumes of road traffic, high population density, a large industrial base and where there is stagnation in the atmosphere (windswept areas tend to suffer less, but the problem may just have been transferred elsewhere – the ‘acid rain’ issue).
Legislation has targeted emissions from industry and – increasingly – transport with varying degrees of success in different parts of the world. However, air pollution remains dangerously high in cities throughout the world.
Cities which have grown up organically over hundreds of years have inherited transport and energy infrastructures which are difficult to dismantle. European cities currently suffer levels of O3, PM10 and NO2 well in excess of the EU targets for 2005-2010 – and even in rural areas levels of O3 and PM10 can be an issue. Public policy makers face major challenges to introduce change. Legislation is being passed to implement a combination of mechanisms acting as an incentive for positive changes in city living patterns and/or penalties for the old behaviour patterns.
Eco Cities and Towns
In a planet of soaring population numbers, the ideal of self sufficiency for a single home in an idyllic rural environment is unattainable for more than a very small minority of people. However, the concept of sustainable communities may be more realistic. Environmentally friendly cities or communities are not new. Long before the ‘eco-’ tag came into common usage, Curitiba, in Brazil, had developed its acclaimed Integrated Transport Network and was implementing a host of what would today be described as ‘sustainable’ measures under an urban Master Plan which was approved in 1966. Curitiba is upheld as an example of the ability of strong urban planning to smooth the integration of migrants during a period of rapid population growth. 
An anticipated rise in the population of the UK from 61 million to 65 million by 2016 was one of the drivers behind the UK Government’s proposal to build ten ‘eco-towns’, as part of its target to build 3 million new homes by 2020. However, the eco-town plans have faced a barrage of criticism from various sources: the renowned architect Lord Rogers has described them as the “biggest mistake the Government could make”. A number of the original applicants have opted out of the running even before the shortlist has been drawn up. As well as local objections, concerns have included the withdrawal of high profile participants such as the Tesco supermarket chain and the Wellcome Trust. Lawyers for the Local Government Association have also raised the possibility of a legal objection as the plans have bypassed local authorities.
A major criticism of the UK proposals is that the towns are to be built on greenfield sites rather than disused urban sites. The locations of some of the towns have also raised concerns about transport policy: the Government target is for over half of all journeys from the eco-towns to be made sustainably, but locating the towns at a distance to existing public transport infrastructure is likely to make this target difficult to achieve. Furthermore, building an entirely new town requires large amounts of energy and materials and cannot claim to be a ‘zero carbon’ process: even if these communities contain highly energy efficient buildings and use only renewable energy, the low carbon attributes kick in only after the construction process has been completed.
The shortlist of ten potential eco-town sites, originally scheduled for publication in October, has been delayed until next year. With house building generally suffering its worst recession in decades as a result of the credit crunch, a review of the eco-town policy is looking increasingly likely.
In contrast to the controversy surrounding the eco-towns, the UK’s first eco-community, the Beddington Zero Energy Development (BedZED), is held up as a model of sustainable living. BedZED was built on reclaimed land and there was an emphasis on integration with the existing local community. BedZED developer, the Peabody Trust, acknowledges that the techniques used in the “village” (around 80 homes and some commercial buildings) are not “particularly high tech”. The emphasis, rather, is on the design. All energy comes from renewable sources, including solar and a waste wood powered small scale CHP (combined heat and power) plant. This provides district heating (although the need for space heating is significantly reduced due to the design and fabric of the buildings, which are constructed from thermally massive materials which store heat during warm weather for release when temperatures drop – and are also heavily insulated). Low energy lighting, energy efficient appliances and smart meters are integral to the BedZED scheme, and waste water recycling is also in place. The community aims to produce enough electricity from photovoltaic panels to power 40 electric vehicles within ten years.
BedZED and the planned eco-towns in the UK are small fry, however, compared to some of the eco-community projects elsewhere in the world. The $22 billion Masdar project in Abu Dhabi, which is being designed by Foster & Partners, includes a partnership between the Abu Dhabi Government and the Massachusetts Institute of Technology (MIT) for the development of alternative energy projects, including solar and hydrogen power plants and manufacturing facilities. The city, which will be home to 50,000 residents by 2016, is designed to be powered by wind and solar energy, to have zero waste and to be car free (there are plans for a fully automated electric personal transportation system). The Masdar Clean Technology Venture Fund has been established alongside the project to promote sustainable technologies: one of the aims of the Abu Dhabi Government is for Masdar to lead the way in innovation in the design of the cities of the future.
China also has its eco-city project, Dongtan, located on Chongming Island at the mouth of the Yangtze Delta near Shanghai. Dongtan has been designed by UK engineering firm Arup and financed by Irish property developer, Treasury Holdings. The STAR (Sustainable Technologies and Renewables) Project, developed in conjunction with the University of East Anglia in Norwich and at the heart of the plans for Dongtan, comprises a renewable energy station to power the city. The first phase is scheduled for completion by 2010 and Dongtan is ultimately expected to house 80,000 people. However, progress on the eco-city is reportedly slow. There have been rumours that Dongtan has faced problems with financing – and the project has been subject to criticism that it threatens the eco-system of the island, which is one of the last remaining wetlands in China (although a Nature Conservation Area has been created to the east of the city).
Throughout Europe, eco-community projects are well established. The highly acclaimed Bo01 project for 300,000 residents in Malmo, Sweden is regenerating an area which was suffering from the decline of traditional industry. The Bo01 project will draw upon geothermal energy for up to 80% of its requirements, with the remaining energy coming from solar and wind. Bo02 and Bo03 projects are already in the pipeline. Also in Sweden, Stockholm has its Hammarby Sjostad development. Other successful eco-communities include Eko-Viikki in Helsinki, Finland; Kronsberg in Hanover, Germany; the Vauban Quarter of Freiburg, Germany; and Neuchatel’s Ecoparc in Switzerland.
In the US, there are a number of experimental eco-town developments at varying stages of maturity. Arcosanti, designed by Italian architect Paolo Soleri, is an experimental town in the Arizona desert. It has been under construction since the 1970s, financed by the Cosanti Foundation. A collaboration between the Cosanti Foundation and the American Hydrogen Association (AHA) aims to make Arcosanti completely energy self-sufficient. The plans incorporate the storage of solar energy as hydrogen and a biomass conversion plant, to convert waste into hydrogen. In California, the Califia eco-community is in the planning stage.
Eco Buildings
Building new communities in reclaimed urban areas, rather than on greenfield sites, is championed by London-based architect, Thomas Teatum. He has put forward a radical solution to London’s housing problems in the form of a proposal for a 1,500-metre high super tower, the New Town Tower. The super tower, which would be built in phases, would ultimately contain 450 floors and would be home to a population of 100,000 people. With a diameter of 150 metres, the total footprint of just 17,500m2 would be tiny compared to those for equivalent population densities elsewhere in London (an average of 8km2 in Kensington & Chelsea and 20km2 for the city as a whole per 100,000 inhabitants), Surprisingly, at least to some, London is in fact one of the least dense cities in the world.
The tower is conceived as “a vertical extrusion of the city – a new town in the sky complete with parks, public squares, schools and hospitals”. The facade is the load-bearing core for the tower, which releases the centre from a structural role and makes it possible to create large circular openings which act as communal space for the residents (parks, open-air theatres, tennis courts, etc.). Access is from a public walkway that spirals around the outside of the tower. The combined public spaces have an area of 150,000m2 – almost as large as Regents Park. The tower has five circulation cores, one of which contains mass vertical transport units. Water and household waste is recycled within the tower, with fresh water being harvested and filtered from the clouds (the height of 1,500 metres is the average level of cloud cover).
A super tower project is highly unlikely to receive planning permission in the current political environment in London. The recent election of Boris Johnson as the Mayor of London has resulted in the reversal of some of the policies of his predecessor, Ken Livingstone, in particular regarding tall buildings, to which Johnson is opposed. However, the concept may be one which society will need to revisit at some point in the future.
In fact, a host of less controversial (and not so tall) eco-buildings are already under construction or in final planning stages around the world. The first of Italy-based architect David Fisher’s “buildings in motion” is being built in Dubai by the Dynamic Group.
The 80-floor tower, which will cost $700 million, surrounds a central core around which each floor revolves – permitting optimal use of sun/shade for heating/cooling. Between each floor a horizontal wind turbine generates electricity, which can be connected back to the grid. A second rotating tower is planned for Moscow, where the developer is the Mirax Group.
Around the world, corporate property is estimated to account for approximately one- fifth of global CO2 emissions, if the total carbon footprint is taken into account (energy use, water production and waste). Initiatives such as the ‘environment code’, formulated by the Investment Property Databank, CB Richard Ellis and Bureau Veritas, offer a template for the measurement of environmental information from real estate which is applicable around the world, irrespective of local planning legislation. In cities such as New York, new buildings are increasingly following environmental guidelines. The cost of constructing a ‘green’ building is typically higher (the US Green Building Council estimates that the cost is typically around 5% above that of building using traditional techniques) – but can be recouped over time through energy savings.
The challenge of improving the carbon footprints of old buildings is less appealing than a new build project. However, a focus on older buildings can result in major savings in terms of emissions through the retrofitting of appropriate energy efficient technologies, opening up major opportunities for clean technology companies in those areas.
Urban Transport
City authorities around the world are struggling to come up with innovative solutions for urban transport. London’s Congestion Charge – a flat charge on all drivers who enter the city centre during normal working hours – has not been copied widely. (An attempt by Mayor Bloomberg to introduce a congestion charge in New York was prevented by the courts on the grounds that the public transport system did not provide an alternative.) However, the model of London’s Low Emissions Zone (LEZ), introduced earlier this year, is being investigated by cities around the world. The London LEZ model involves banning heavy polluters. Large vehicles (buses, trucks) are required to either install a retrofit or buy a new engine to comply with the standards to enter the zone – which covers a wide area around the city – or face a heavy fine of £200 per day. As with the Congestion Charge, the authorities earn revenues. However, additional benefits are a guaranteed reduction in emissions and – for companies involved in emissions reduction businesses – a sufficiently critical volume of demand for products to make research and development commercially viable.
Elsewhere, the example of Delhi in India is interesting. In the city, which was previously one of the most polluted in Asia, the retrofitting of compressed natural gas (CNG) engines in all vehicles used for public transport (buses, taxis and moto-rickshaws) was mandated as a result of a court order. The court ruling on action to reduce emissions in Delhi was prompted by local concerns about the growing levels of illness related to emissions.
The replacement of dirty diesel engines with CNG engines has certainly cleaned up the city’s air. However, there have also been disadvantages. Five years after the switch-over took effect there is still a lack of capacity at filling stations, and queues to fill up on CNG are commonplace. A more significant side effect, however, is that the incidence of some health problems, notably respiratory diseases, has in fact continued to increase. This can be attributed to the high levels of NOx prevalent in CNG and the Delhi authorities are currently focusing on methods of reducing NOx levels, which may prove more challenging.
In Latin America, the Bus Rapid Transport systems developed by Curitiba and emulated in cities such as Bogotá in Colombia have had a measurable impact in terms of fuel savings, and thereby reductions in greenhouse gas emissions, at a relatively low cost.
Meanwhile, in Europe, buses in Stockholm, Sweden, which aims to become a carbon neutral city, run on ethanol, while in Lille, France, the policy is to run buses on biomethane, recovered from the city’s landfill sites.
And in many cities there are moves to encourage the use of electric vehicles, both for personal transport (cars) and fleets of vans.
Much is being done in terms of transport policy already, but there is still a long way to go. As with the building sector, an enormous opportunity exists for clean technology companies to step in and provide solutions – in terms of both retrofit technology and new technology. Cleantech has a big future in the City.
