Low Carbon Cities: Transforming Urban Systems, the third book in the Earthscan Series on Sustainable Design edited by Curtin University professor Steffen Lehmann, brings together research and case studies that encapsulate the major issues that urban planners, architects, policy-makers, sustainability experts, engineers and landscape architects are grappling with on a daily basis.
The core theme of the book is the re-engineering of urban systems, in terms of reducing the size of the urban carbon footprint, creating regenerative cities and also mitigating the escalating impacts of climate change.
It packs a lot of detail and expertise into the text, illustrated throughout with diagrams, case study photos, plans and tables to create a highly informative global picture that melds theory with what’s actually happening on the ground in places ranging from the Sydney CBD through to India, the Republic of Korea, northern Europe and Detroit in the USA.
The book is divided into three sections. The first sets out the framework of a definition for low-carbon cities and the issues that are crucial to the process of transition. It also canvasses a range of classic texts and different schools of thought, from biomimicry and solar-responsiveness in urban design through to low carbon transport systems and an Australian study on how cities impact their resource hinterland.
The second section explores what it actually means in practical terms to design a low-carbon city, bringing together both theories and outcomes with an interdisciplinary perspective.
Lehmann told The Fifth Estate the contributions were specifically selected for a precinct-scale approach, not just individual buildings. So while One Bligh Street in Sydney is featured in a contributed essay by Christoph Ingenhoven, Martin Reuter and Ben Dieckmann, it is within the context of an essay that examines how both that building and another unbuilt project by Ingenhoven designed for Ireland illustrate the principles of green urbanism and the regenerative approach.
“Neighbourhoods are the right scale for transformation. The whole city is too big, and a single building is too small. The precinct scale is right,” Lehmann says.
The third part of the book looks at the urban micro-climate and mitigating heat stress – how precincts can be designed and built to be cooler, and what the opportunities are for mitigating the urban heat island effect in existing urban areas.
David Sailor, founder of the US-based Green Building Research Centre, does an excellent step-through of the science around urban micro-climates and heat mitigation, and outlines the need to consider both private and public benefit.
For example, he writes, for a home owner a light-coloured, low-albedo roof in a cooling-reliant climate has a positive benefit in terms of reduced energy bills for cooling, even through its contribution to the overall public benefit is small. Conversely, urban greening has a large public benefit, but its benefit for the private individual may appear small.
Sailor also stresses the importance of planners taking the long-term view, including examining co-benefits, and factoring in the maintenance, operation and longevity of a variety of urban heat mitigation measures in determining the final matrix of approaches.
Lehmann says that because the climate is heating up and greenhouse gas emissions are continuing to rise, mitigating the impacts of heat stress is a crucial element of the transition to low carbon cities.
“It’s about looking at what kind of city do we want and need,” he says.
“What do we do as urban planners and architects? What kind of growth do we want?”
One of the key issues, he says, is that under current models and methodologies, increasing economic growth and consumption translates into increased GHG emissions. The alternative is to have a competitive economy that succeeds due to resource efficiency, rather than continuing down the 20th century-thinking path of infinite growth through ever-increasing consumption of resources.
“The industrial paradigm locked us into a certain system that’s a system of consumption – that’s the issue – that the systems in place at the city level force us to generate a lot of emissions.”
Lehmann says the question is not only about how the developed nations such as Australia can make the transition, but also, “How can we help the developing world to come out of poverty?”
Some of the essays in the book, such as Shirpa Narang Suri’s From sustainable to low carbon cities: is India’s urban transformation triggering paradigm shift, touch on this issue of sustainable development and how it can occur within the planetary boundaries.
Lehmann says the two final books in the series, one around density and sustainability, the final one around wood in the city and the use of timber buildings in the urban context, are currently being prepared.
On density, he says, there are potentially connotations to the word that summon up images of the high rises of Hong Kong – built environments that are not what many consider exemplary. Instead, he says he prefers the word “compactness” to describe an approach to urban forms that has a smaller footprint while still providing living and working and recreational space for growing populations.
The timber-focused book, he says, will also examine how to set up a positive green supply chain, and how timber can be used to transform new buildings and districts into carbon sinks.