Sustainable Cities Network

Urban Heat Island Effect: Research & Collaboration

2010-09-08T01:09:43Z

From “Urban cool” by Roland Ennos:

Cities are hot, noisy places with poor air quality that are prone to flash flooding during storms. In cities we are guilty of using huge amounts of energy for cooling in summer, heating in winter and transport the whole year round. Making cities more pleasant and sustainable places in which to live is therefore one of the key goals of environmental research, and it is one that physicists are ideally suited to contribute to, since most urban environmental problems are best understood in physical terms.

Physicists across the world, particularly those working in environmental physics and meteorology, are now collaborating with scientists from other disciplines to study the environmental performance of cities and establish how “green” these urban environments are. One particularly important environmental characteristic of cities is the “urban heat island”, whereby urban areas are hotter than their surrounding countryside. This is a real problem, which will be made even worse by climate change. It has therefore become a prime focus of research.

The urban heat island

Cities are typically about 4 °C hotter than the surrounding countryside and the larger they are, the bigger the difference. To understand why, we must consider the energy balance of the two areas (figure 1). Although heating, air-conditioning and transport all produce energy in cities, this is a surprisingly small component of their heat balance – only about 50 W m–2. Except for in winter, this is dwarfed by the energy we receive from the Sun, which even in the UK peaks at more than 800 W m–2. The difference between temperatures in a city and the surrounding countryside is therefore mostly due to what happens to the Sun’s energy in the two environments.

In rural areas, vegetation reflects about a quarter of the incoming short-wave radiation (visible light or shorter wavelengths). Of the three-quarters that is absorbed, much of the energy is used to evaporate water from leaves – a process known as “evapotranspiration”. This cools the vegetation, which therefore radiates little long-wave radiation (infrared), and even less energy remains to heat the air by convection and to heat the soil by conduction.

In cities, where vegetation has largely been replaced by buildings and roads, the energy balance is dramatically altered. Dark, artificial materials reflect less – and absorb more – radiation than vegetation. This lower “albedo” means that only about 10% of the Sun’s radiation is reflected; this figure is even lower in high-rise cities where light is reflected down into urban “canyons”. Almost all of this energy goes into heating the dry roads and roofs, where it is either stored in bricks and mortar or heats the air above, thus raising daytime surface and air temperatures well above those of the surrounding countryside.

At night the difference in temperature between the countryside and the urban heat island can become even more pronounced. Cities cool down more slowly because there is more heat stored in its buildings, which continues to dissipate into the night; there is more pollution to trap long-wave radiation; and within urban canyons less of the cool sky is visible, so less radiation can escape.

All this causes major problems for city-dwellers. The rise in urban air temperature above that of the surrounding countryside, which can reach 7 °C in a metropolis like London, makes cities less comfortable places to live in during the summer months. Soaring temperatures increase ill health and can even kill people during heatwaves: it is thought that more than 35,000 people died in Europe as a result of the 2003 heatwave, most of them in towns and cities. The urban heat island also makes cities less sustainable, since it increases the amount of energy used for air-conditioning – energy that is pumped into the open air and just makes the situation worse. Fortunately, physics shows that two very different methods could be used to alleviate the urban heat island: using “cool surfaces”; and using vegetation, or “green infrastructure”.

Read the rest of this informative article by Roland Ennos on Physics World.

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Fit Cities: Design & Policy Collaboration

2010-09-07T01:29:59Z

Source: MetropolisMag

From “Design + Policy = Fit Cities” by Susan Szenasy:

George Miller, the current president of the American Institute of Architects and a local [NY] practitioner, opened the fifth annual Fit City symposium at the Center for Architecture, in Manhattan, by challenging the crowd to rethink the planning, architecture, and design of our metropolis, with the goal of encouraging physical activity and healthy lifestyles. Our city is in the midst of a health emergency: 43 percent of elementary school children are overweight or obese, and diabetes rates are climbing, driving health-care costs up and life expectancies down. Clearly, a shift in mind-set is needed. “Ninety percent of the game is half mental,” Miller quipped, channeling Yogi Berra, master of the malaprop. That morning in May foretold an era of collaboration between policy makers and the creative community. Fit City 5, a partnership between the local AIA chapter and the New York City Department of Health and Mental Hygiene, attracted stakeholders from public health, education, and design as well as other concerned citizens.

The commissioners (looking fit, like Mayor Mike, who leads by example) gave an update on their efforts. David Burney, of Design and Construction, said the city’s new Active Design Guidelines are frequently downloaded to addresses far and wide. Janette Sadik-Khan, of Transportation, said the Street Design Manual stresses sustainability, while the “Look” campaign focuses on etiquette to promote safe cycling. Amanda Burden, of City Planning, talked about new zoning regulations that encourage the development of neighborhoods where cars aren’t necessary. Parks and Recreation’s Adrian Benepe reported that hundreds of school playgrounds are being turned into parks, wheelchairs can now get on city beaches with help from special mats, and Blue Cross and Equinox are supporting public-exercise programs. “Health is profitable,” he added.

In addition to creating neighborhoods where children can walk to school and play outdoors, and where people can buy fresh, locally grown food, a fit city must also pay attention to the design of its interior spaces. The health-care specialist Robin Guenther, of Perkins + Will, drew a correlation between the severity of illnesses and increased energy use in hospitals. Smart planning can save fossil fuels and encourage exercise by slowing down elevators, making stairs visible and attractive, and putting them where people gather. Les Bluestone, a developer, described housing built for first-time buyers with rooftop hydroponic gardens for growing their own produce.

On that balmy spring day, it became clear that New York’s policy makers have joined designers in an effort that is more comprehensive and complex than any single department. They are challenging themselves, and designers, to rethink our aging, unhealthy buildings while celebrating our famous urban density. As I write this, I’ve received an invitation to join a group at the national AIA convention this June to discuss ways to develop research and connections among architects, the USGBC, the Centers for Disease Control and Prevention, and the National Institutes of Health. The solutions we come up with must be “half mental,” as Yogi might say.

Orginal article by Susan Szenasy for MetropolisMag.

Hand-made hives for backyard bee-keeping

2010-09-07T01:15:53Z

Source: Springwise

Keeping bees in an urban environment can be tricky and unhealthy for the bees. Now there is now a bee keeping hive for urban farmers that also concentrates on the health of your bees while making it easy to upkeep the hive.

Read the full article.

Collaborative Democracy

2010-09-03T05:42:34Z

Source: Worldchanging.com

Image: infomatique from flickr CC

This article is from a remixed talk by Beth Noveck’s on “Transparent Government“. The talk was given as part of the Long Now Foundation‘s Seminars about Long-Term Thinking. The talks were remixed by Hassan Masum, are made available under a Creative Commons by-nc-sa 2.5 license.

The talk describes a social experiment “which seized upon the truth that each of us is an expert in something” that was designed to investigate ways of re-energising democratic decision making. It started from the following point,

We have been concentrating decision-making power in the hands of too few people – whether legislatures, or cabinet officials, or bureaucrats and agencies like the patent office. We construct our institutional practices around the notion that this is the best way that we have to make decisions. Even though we do not have a system of monarchy or aristocracy, we still believe in the notion of political expertise, and the notion that we have to rest power at the center.

What exacerbates this problem is that we are making long-term decisions that affect the fate of our planet. The fate of our economy, and of major systems of health care and education and environment, are being decided by people who are in short-term political positions. We have a disconnect between the long-term effect of what we do, and short-term electoral cycles.

We have to look at the ways we can reengineer our institutions to take advantage of the expertise that comes from outside the center, and bring it into the way that we make decisions.

Read the full article on Worldchanging

Buckminster Fuller Challenge: Open for Entry

2010-09-01T00:50:39Z

The Buckminster Fuller Challenge is an annual international design Challenge awarding $100,000 to support the development and implementation of a strategy that has significant potential to solve humanity’s most pressing problems. It attracts bold, visionary, tangible initiatives focused on a well-defined need of critical importance. Winning solutions are regionally specific yet globally applicable and present a truly comprehensive, anticipatory, integrated approach to solving the world’s complex problems.

» Applications are now being accepted: How to Enter

» Deadline is Monday, October 4, 2010 at 5pm, Eastern Standard Time

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Minimonos & Other Games for Change

2010-08-31T02:11:28Z

Source: Worldchanging

From “Games for Change: An Interview with MiniMonos and a Look Back” by Amanda Reed:

Jeff Ramos of GameCulturalist.com recently interviewed Kaila Colbin from MiniMonos.com, which is a virtual world that encourages children and parents to practice sustainability, generosity and community. The game was developed by a group of New Zealanders who were trained by Al Gore to be Climate Ambassadors after The Inconvenient Truth came out.

Here is an excerpt from the interview in which Colbin talks about the real world projects the players of MiniMonos develop as a result of the game’s lessons:

What have you learned about gaming and social interaction because of MiniMonos?

We’ve learned that kids online will continually surprise and delight you. We’ve learned that kids are far more clued up about the environment than we had realized, and that they place far more explicit importance on it than we had realized. We’ve learned that they really appreciate being listened to, and the importance of a sense of belonging. We’ve also learned that they’ll go to astonishing lengths to get a rare virtual item!

We’ve been stunned and humbled by the many ways in which MiniMonos members have picked up the sustainability gauntlet and carried these messages into the real world. We’re seeing a generation of children who already care for the environment, who are tremendously generous, fun-loving, and supportive of each other.

We do everything we can to reinforce the need to take real-world action. We turned off the servers for Earth Hour, and every new membership provides clean drinking water for children in India…

Read the full interview and learn more about MiniMonos and the game developers. As a relative newbie to Worldchanging and games for change, this interview inspired me to look into the Worldchanging archives to see what other games and virtual worlds had been written about in the past…the extensive collection of articles I found was stunning. If you’re interested in checking some or all of them out, the list has quotes from each piece.

Check out the list compiled by Amanda Reed on WorldChanging.

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Floating Home

2010-08-31T01:13:25Z

Source: Metropolis Magazine

A competition proposal to develop a floating city has developed into ‘the world’s first off-the-grid floating building’ in Rotterdam.

Towed into place in the Rijnhaven harbor late this spring, the 10,764-square-foot pavilion is made of three geodesic domes designed by Bart Roeffen, a local architect. It grew out of a competition proposal for a floating city developed by Roeffen and fellow students at the Delft University of Technology. “We thought it was a brilliant idea to promote Rotterdam as a city on the water to anticipate the effects of climate change,” says Arnoud Molenaar, program director of the Rotterdam Climate Proof Program.

The city is expanding its current harbour by 20% and this expansion has created the space for up to 5000 similar floating structures that could potentially use the harbours and docks that are being superseded.

Original article by Cathryn Drake on Metropolis Magazine

Building Niches for Biodiversity

2010-08-26T01:08:38Z

Source: Treehugger

From “Biodiversity for Low and Zero Carbon Buildings: A Technical Guide for New Build (Book Review)” by Kimberley Mok:

With major declines observed in bee, bat, bird and other critical species, it makes sense that newer built environments now being designed with zero- or low-carbon status in mind should also integrate ways to boost wildlife diversity as well. That’s the premise of Biodiversity for Low and Zero Carbon Buildings: A Technical Guide for New Build by Dr. Carol Williams.

Dr. Williams, who is associated with the UK-based Bat Conservation Trust (BCT), points out that imperfections in the craftsmanship of traditional buildings allowed certain species to find ecological niches and roosting opportunities right alongside humans. Not so with newer, ‘air-tight’ construction, hence the need to accommodate and integrate built-in habitats for now-threatened species ranging from certain bats, owls and peregrine falcons. Thus, the book is apparently the first of its kind to consciously target biodiversity enhancement in new developments, rather than retrofitting existing structures.

Unless biodiversity is considered early on in the design process, these ever more stringent demands for increased energy efficiency of buildings will lead to losses in the biodiversity that have shared our built environment for centuries. This book addresses this issue because if we do not, there will be very few, if any, future roosting opportunities for bats or nesting opportunities for birds in our buildings. Without these measures, key species will be adversely affected by new developments; not only meaning a failure to achieve truly sustainable building, but also an erosion of the quality of life we all hope to experience in our working and home environments.

With a focus on the sustainable building process and wildlife in the United Kingdom, the book is practical in its scope, providing plenty of tables and technical information on how to size and orient suitable building elements that each particular species could call home. There’s also valuable information on prefabricated wildlife-friendly components from various manufacturers, plus a chapter on living walls, roof gardens and artificial lighting. Full of clearly annotated architectural drawings, colour photos and well-organised information, this book will be an excellent reference for architects and developers in the sustainable building industry.

Original article by Kimberley Mok on Treehugger.

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Solar is Cost-Competitive with Nuclear: Report

2010-08-24T03:39:36Z

Source: Worldchanging

From “Scaling Up Solar: The Global Implications of a New Study that Says Solar Power Is Cost Competitive with Nuclear Power” by Olivia Boyd:

The sunshine of North Carolina, a state on America’s Atlantic seaboard, has long been a draw for tourists seeking a little southern warmth on the region’s beaches. But holiday companies are not the only ones trumpeting a good local deal. The price of the state’s solar-generated electricity has fallen so far that it is now cheaper than new nuclear power, according to a report published in July by researchers at the state’s Duke University. The authors say their figures indicate a “historic crossover” that significantly strengthens the case for investment in renewable energy – and weakens the arguments for large-scale, international nuclear development.

Solar power is usually branded as a clean but expensive energy source, incapable of competing on economic grounds with more established alternatives, such as nuclear. The outspoken pro-nuclear stance adopted by a raft of iconic environmental figures – James Lovelock, Stewart Brand, Patrick Moore – has helped to instill in policy making circles the sense that this is the only power source that can restructure our energy supply at the pace, scale and price required by the pressures of rapid climate change. This study, which was co-authored by former chair of Duke University’s economics department John Blackburn and commissioned by NC Warn, a clean-energy NGO with a firm anti-nuclear bent, challenges that view. “This report should end the argument for risking billions of public dollars on new nuclear projects,” says Jim Warren, NC Warn director.

The paper states that commercial-scale solar developers in North Carolina are already offering utilities electricity at 14 cents or less per kilowatt hour. Meanwhile, two power companies – Duke Energy and Progress Energy – are pushing ahead with plans for local nuclear plants that, at current estimates, would generate electricity at the higher rate of 14 to 18 cents per kilowatt-hour.

The “crossover” is largely thanks to a marked decline in the costs of solar photovoltaic (PV) systems seen over the past decade. The study cites figures [PDF] from the Lawrence Berkeley National Laboratory indicating that the cost of solar PV fell from US$12 (81 yuan) per installed watt in 1998 to US$8 (54 yuan) in 2008, on average – a one third drop in 10 years. In 2008 and 2009, costs fell even more rapidly, bringing the 12-year fall to 50%. Meanwhile, the expense of nuclear has ballooned. The estimated cost of construction in the United States at the start of the nuclear renaissance was around US$2 billion (13.6 billion yuan) per reactor. It now stands at around US$10 billion (67.8 billion yuan).

The Duke University research is, of course, limited in geographical focus – the 14 cents figure, which is net of public subsidies, is specific to the North Carolinian regulatory context, where (as in many places) tax benefits and incentive payments for solar electricity help lower costs to customers. But the authors argue that solar is expected to be cost-competitive without subsidies within the decade. And their overall message – that solar and other renewables represent increasingly good value compared to alternatives – is not unique. Jeremy Leggett, the founder of the UK’s largest solar company, Solarcentury, predicts “even cloudy Britain” will reach residential grid parity between solar and fossil-fuel power within five years, while Google is claiming breakthroughs in its bid to make renewables cheaper than coal.

And the pace of development on the ground is startling. At the end of 2009, total worldwide solar installations passed the 22,000-megawatt mark. During that year, more than 7,000 megawatts of solar-generating capacity had been built globally, half of which was in Germany.

“When you begin seeing solar production on this level, it starts making a significant difference. It’s no longer a niche thing,” says Antony Froggatt, senior research fellow in the energy, environment and development program at UK think-tank Chatham House. “It’s very clear that the learning curve for solar is very fast. We are seeing very, very rapid production and economy of scale is clearly crucial.”

Blackburn and his co-author, Sam Cunningham, argue that the strengthening renewables sector, combined with the perceived financial risks of new nuclear, is influencing investor behaviour: “Very few other states [American states other than North Carolina] are still seriously considering new nuclear plants. Some have canceled projects, citing continually rising costs with little sign of progress toward commencing construction. Many states with competitive electricity markets are developing their clean energy systems as rapidly as possible.”

Read the full article by Olivia Boyd.

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Getting Produce to Market: Transport “Innovation”

2010-08-10T01:52:09Z

Source: Nourishing the Planet: Worldwatch Institute

From “Innovation of the Week: Getting to the Market” by Molly Theobald:

For many farmers, an abundant harvest is only the first step toward feeding their families and earning an income. Vegetables ripening in the field—or even harvested and stored nearby—are still a long way from the market where they can be sold for a profit.

One farmer in Sudan’s Kebkabyia province, Abdall Omer Saeedo, has to travel 10 kilometres twice a week to the nearest market to sell his vegetables and green fodder. Without a cart, truck, or other means of transporting a large amount of goods efficiently, he couldn’t make enough money to cover his production and packing costs, let alone the cost of seeds for the next season, education for his children, and other household needs. And after making it to market with his 10 sacks and five bags of produce on the back of his donkey, he was still at risk for loss if he wasn’t able to sell it all. Instead of dealing with the hassle of trying to pack it back home again, he would throw away whatever wasn’t sold.

Saeedo sought the help of Practical Action, a development non-profit that uses technology to help people gain access to basic services like clean water and sanitation in order to improve food production and incomes. Working with local metal workers, the organisation designed a donkey cart for him. Now, Saeedo is not only able to cart his produce to market twice a week, he can also easily bring back whatever he is unable to sell. His income has increased along with the quality and quantity of his product, which is no longer lost or destroyed by travel time and conditions.

Practical Action’s transportation innovations are helping to improve farmer livelihoods throughout sub-Saharan Africa and around the world. In Kenya, the organisation introduced bicycle taxis as a way for people to earn a living, as well as an energy-efficient means to transport people from place to place. In Nepal, Practical Action’s bicycle ambulances help carry sick or injured people from remote areas to hospitals safely and comfortably. And in Sri Lanka, the group’s bicycle trailers—capable of carrying loads of up to 200 kilograms—are used to transport goods to market, people to hospitals, and even books to local communities.

Read the full article by Molly Theobald.

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