̽��ֱ�� of Cambridge - Douglas Crawford-Brown

Going green: why don't we all do it?

lw355 — Fri, 10 Jun 2016 09:20:54 +0000

For those of us who pay fuel bills, saving energy by insulating our homes or perhaps installing solar panels seems to make perfect sense. It saves money, therefore as rational human beings why don’t we all do it?

It’s a question that preoccupies Dr Franz Fuerst from the Department of Land Economy. “If you just follow the bottom line, you should see a lot more investment in energy efficiency purely from a profit-maximising perspective. And we should see even more if we take the costs of climate change into account. Why it’s not happening is a puzzle that keeps me awake at night,” he admits.

Fascinated to find the factors at play, Fuerst and his colleague Ante Busic-Sontic started supplementing their economic models with insights derived from psychology.

According to their newly developed theoretical framework, our personalities – as described by the ‘Big Five’ personality traits of Openness, Conscientiousness, Extraversion, Agreeableness and Neuroticism – have a major influence on our decisions about investing in energy efficiency because of the way they relate to our attitudes to risk and the environment.

To provide evidence for the theory, they analysed data from the Understanding Society survey (previously called the British Household Panel Survey), which since 2009 has surveyed some 50,000 households and 100,000 individuals every year. “It’s a rich data set that captures all possible indicators for a household, including energy efficiency decisions and attitudes as well as personality traits,” says Fuerst.

They found that personality traits matter in terms of investment decisions in energy efficiency, even when controlled for drivers such as income, gender and education, although some personality traits are more strongly associated with investment decisions than others.

“Making any investment is almost always a risky undertaking. This is particularly true for many energy efficiency investments that require upfront capital expenditure while the actual energy savings and payback periods occur at a later time, which introduces risk. But what is considered an acceptable level of risk differs widely across people and households.”

This makes attitudes toward risk an interesting factor to consider when explaining energy efficiency investment decisions. “Openness, which is generally related to lower risk aversion, has a distinct impact on investment behaviour and is our strongest trait,” he explains. “Neuroticism and Agreeableness lead people to be more risk averse, while Extraversion has a positive association with risk. Conscientiousness instead shows only a weak impact on investment behaviour through the risk channel.”

They also found sizeable differences between personality traits and environmental attitudes and the same personality traits and actual investment outcomes. “We find that with rising income, personality traits become more important as factors that determine green investment. Your personality traits don’t get a chance to manifest themselves if you lack the money to invest.”

Given policymakers’ limited success in encouraging more of us to invest in energy efficiency, understanding how personality affects these decisions could help us develop more effective policies and incentives, Fuerst believes.

“Because perceived risk and risk aversion are the two key mediating factors, there is scope for developing more bespoke financial products that are attractive if you have a very low appetite for risk.”

There is already a range of financing options available that involve transferring some or all of the investment risk from the property owner to a private or public sector third party but these are currently focused on larger organisations and businesses and have yet to be rolled out to households on a large scale. Additionally, information campaigns can help to increase the awareness among the risk averse that the ‘do nothing’ option is by no means risk-free and might in fact be the riskiest choice. “For example, via the larger exposure to future energy prices, tightening regulations or a potential drop in market value for properties with poor energy efficiency,” he says.

Environmental decisions, are affected not just by personality and attitudes to risk, but also by urban design and social conditions – factors that Professor Doug Crawford-Brown and PhD student Rosalyn Old are exploring.

“Cities are increasingly incorporating sustainability metrics in the way buildings are built, the materials and resources used by occupants, and how waste is disposed of,” Crawford-Brown explains. “But how can we ensure cities will meet these metrics and perform sustainably? One of the most important challenges is to understand how people are motivated to act sustainably, and how those motivations are stimulated by the design and operations of communities.”

To understand more about the take up and use of green technologies, Old is studying the ̽��ֱ��’s North West Cambridge (NWC) Development, an extension to the city that is currently being built. “House builders are under pressure to include green technologies in new buildings, yet the take up and use of these technologies is uncertain,” she says. “This is a good opportunity to look at what’s special about NWC, how energy and carbon can be saved in a development like this, and learn lessons that can be transferred to future sites.”

Taking a range of technologies – from solar panels and water recycling to the district heating system and electric car charging points – that are being built into NWC, Old is modelling which technologies will be most efficient according to how people behave.

Residents have yet to move into NWC, so she is surveying equivalent demographic groups in Cambridge, such as postgraduates, key workers and families, to find out about their values, norms and attitudes so that she can model how they are likely to use the green technologies on offer.

“We can look at the energy impact given certain scenarios,” she explains. “For example, if 50% of postgraduates are ‘keen greens’ and they all cycle to their departments, the model will tell us the energy impact.”

And because the model includes the ability to interrogate different scenarios, it allows project managers to calculate the carbon savings associated with encouraging certain groups to be more environmentally conscious, opening up new ways of nudging residents to be greener.

Old hopes the model will help shape future phases of NWC, as well as other sustainable city sites and other sectors: “What we discover about how to shift people between different behavioural groups is important and can be used in policy work in many sectors. Even small changes in urban design can make a big difference.”

From wind turbines and solar photovoltaics to grey water recycling and electric vehicles, technology is making it ever easier for us to be green – yet many of us are not. Now, Cambridge researchers are discovering that our personalities and communities have a major impact on our environmental decisions, opening up new ways to ‘nudge’ us into saving energy and carbon.

One of the most important challenges is to understand how people are motivated to act sustainably, and how those motivations are stimulated by the design and operations of communities

Douglas Crawford-Brown

Josef Stuefer

Green light

Smart city, MAGIC city

Nudging people to make sustainable lifestyle choices is one thing, but can a city be nudged towards energy efficient investments, lower emissions and cleaner air?

Cities cope with pollution and uncomfortable temperatures by closing windows and installing units that heat, ventilate and air condition, which themselves guzzle energy and frustrate efforts to decarbonise.

A new interdisciplinary research project aims to halt this unsustainable trend by creating solutions that make cities cleaner with minimum use of energy. ̽��ֱ��key to progress, says project leader Professor Paul Linden, in the Department of Applied Mathematics and Theoretical Physics, is to start treating the city as a complete, integrated system.

“Experience over the past two decades suggests that when infrastructure investment works closely with innovative urban design across a city, there’s a shift towards low emissions and lower carbon travel through spontaneous citizen choices,” he explains.

̽��ֱ��£4.1 million Managing Air for Clean Inner Cities (MAGIC) project will link data fed from sensors monitoring a city’s air to an understanding of air flow inside and outside buildings, and innovations in natural ventilation processes. ̽��ֱ��idea is to develop an integrated suite of models to manage air quality and temperature (and, consequently, energy, carbon, health and wellbeing) – at the level of buildings, blocks and across the whole city.

To do so, engineers, chemists, mathematicians, architects and geographers from 12 university and industry organisations will be working together, with funding from the Engineering and Physical Sciences Research Council.

̽��ֱ��model and associated decision support system will, for example, provide information on how traffic routes can be optimised to reduce pollution, and the cost-benefits of introducing cycling routes and green spaces. But the main value of understanding energy use and air flow, says Linden, is that a city can monitor itself continuously – it can, in effect, become its own natural air conditioner.

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes

Innovating for the future of cities

Anonymous — Wed, 01 Jun 2016 15:30:00 +0000

There is a clear line of sight on the broad features of the cities of the future.

They will be large, with significantly more than half of the world’s growing population crammed into them.

They will house an increasingly older population, placing stress on services to the elderly and a rising tax burden on young workers whose taxes pay for those services.

They will be environmentally constrained, require a lower environmental impact of almost everything we depend on today, and they will need more resilient infrastructure, buildings and economies as the climate shifts.

In at least the developing world, the megacities will be a complex and messy mix of formal and informal settlements, with no obvious governance structure covering the entire city.

These are very broad sketches of the challenges. ̽��ֱ��more interesting issues revolve around how we respond to those challenges, and how those responses affect the design, operation and governance of cities. How we respond will in turn profoundly influence the quality of life of residents and what it feels like to live in such cities.

̽��ֱ��future depends on the innovations we create and put in place today. But what form might those innovations take? We divide them into the physical city, urban governance and the choices made by the residents of a city. Each is the focus of intensive research at the ̽��ֱ�� of Cambridge in collaboration with our partners elsewhere and in the public and private sectors.

̽��ֱ��physical city

Future cities must become smarter, since resources and services will be stretched to their limits. Our cities today are built on projections of long-term needs, and locked into the infrastructure to meet those needs with a large margin of safety so they are robust against different potential futures. This is wasteful of materials and energy.

Buildings and infrastructure of the future will be fitted with sensors monitoring every aspect of operations from climate to energy performance to material safety and service demand. Energy will flow in real time to where it is most needed. Transport will be directed around areas of high air pollution so human health is preserved. Buildings will be monitored for stresses, allowing actions to be taken before catastrophic failure, reducing the over-engineering of buildings with more concrete and steel than may ever be required.

̽��ֱ��same sensors will monitor the climate and allow buildings and infrastructure to respond so damage from extreme weather events is minimised. ̽��ֱ��technologies for climate adaptation are well known. ̽��ֱ��problem is how to allocate limited technological and financial resources so the overall impact on a city by a changing climate is minimised. This requires understanding the role of specific parts of the physical city in the economy and services. An approach is needed to rationalising adaptation resources so they are used wisely to protect the city’s economy and services, in turn ensuring livelihoods and well-being are preserved. Macroeconomic models linked to engineering knowledge allow decision-makers to understand where adaptation and recovery resources can best be directed to get a city back on its feet after an extreme weather event.

Governance

Cities will become living laboratories for sustainability, requiring changes in governance. Since cities are heterogeneous mixtures of planned and unplanned buildings, formal and informal developments, no single set of solutions to service provision, crime, health or education will work everywhere within the city. Systems of governance will allow for experimentation, testing solutions in some parts of the city but not others, with the design of those trials allowing us to see what works where and under what conditions.

̽��ֱ��city will become a laboratory in the scientific sense, with the language of case-control and cohort studies. ̽��ֱ��messy and complex nature of cities will be turned into an asset, allowing for natural experiments. This in turn requires governance systems that embrace experimentation; politicians who are willing to admit when an experiment has failed and move on to the next experiment; a public that will not penalise those who are brave enough to try something in the face of profound uncertainty and then adjust their decisions when evidence emerges.

Cities will also find an intermediate ground between top-down planning (as in the ‘new towns’ such as Milton Keynes) and bottom-up growth (think of the favelas of South American cities). Bottom-up solutions allow for highly local differences in economies, architectural style, material and energy consumption. However, they can reduce the efficiency of resource use of the city when viewed as a system. ̽��ֱ��‘transmission’ of a future city, sitting somewhere between the Mayor’s office and neighbourhood groups, will enable local solutions to remain local while facilitating solutions for the greater good of the city overall.

̽��ֱ��challenge is to design a governance structure that enables the efficiency of technocratic, systemic control of planning and development to take place while also allowing citizens to develop solutions that work for their local conditions. ̽��ֱ��challenge is to find a system where bottom-up and top-down decisions co-exist comfortably.

People

Citizens must become smarter as well. Future technologies will not simply provide data. They will be linked to data analytics that reflect who is taking decisions, why, when and where. ̽��ֱ��data will be turned into information to guide decisions on (for example) assets, and transmitted in easily understood form to the pinch points where decisions are taken. People will be re-connected to the ebb and flow of material and energy in the city, with much deeper understandings of how their personal actions influence the performance of their city, and how the information around them influences their own decisions on use of materials, energy and services.

Future cities will make increasing use of natural ventilation based on advances in ecology and fluid dynamics. With the transport system dominated by much quieter electric vehicles, windows will be left open, indoor pollution will be reduced and levels of comfort will rise as the heat island effect disappears. Improved walking and cycling paths will bring the benefits of exercise and re-connect people to their neighbourhood activities. Health and well-being will be improved by, rather than be collaterally damaged from, urban life.

These are just three examples of future challenges being explored at the ̽��ֱ�� of Cambridge in collaboration with partners at other universities in the UK and globally, and with public and private sector organisations. Taken together, they are providing the evidence base that will solve the high level and ground level challenges, and enable the top-down and bottom -up solutions, that are emerging as urban life becomes the norm for a growing global population.

Professor Doug Crawford-Brown is at the Department of Land Economy, Professor Lord Robert Mair is at the Department of Engineering and Professor Koen Steemers is at the Department of Architecture.

Today, we commence a month-long focus on the future of cities. To begin, Doug Crawford-Brown, Robert Mair and Koen Steemers describe the challenges our future cities will face and how mitigation depends on the innovations we create and put in place today.

How we respond to these challenges will profoundly influence the quality of life of residents and what it feels like to live in such cities.

Doug Crawford-Brown, Robert Mair, Koen Steemers

GLAS-8

Dark City

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes

What impact will new technology have on tackling emissions?

sj387 — Mon, 21 Oct 2013 09:14:01 +0000

Computational models provide unparalleled insight into current and future demand for water, land and energy, and the impact these demands have on greenhouse gas (GHG) emissions and the environment. What if we could also take into account the fast pace at which new technologies are evolving? This is the aim of a new project in the Cambridge Centre for Climate Change Mitigation Research (4CMR) in the ̽��ֱ�� of Cambridge’s Department of Land Economy.

Dr Jean-Francois Mercure, who leads the research, asserts that building this factor into models will help understanding of the degree to which improvements in energy-consuming technologies and their adoption can help governments reduce emissions: “Technology comes to life through innovation, timely investments and policy incentives, and so it’s important to include technology diffusion and its pace in energy modelling.

“However, this is challenging and most models today attempt to calculate cost-optimal technology roadmaps based on current technology, which is not necessarily likely to happen, and which disregard the process by which new technology regimes come to existence, but also how old technologies endure.”

Technological change occurs constantly, either following innovations in industrial systems or through evolutions of behaviours, such as in the adoption of electric cars. Earlier this year, with funding from the Engineering and Physical Sciences Research Council, Mercure began work on a computational modelling system that takes into account the profile of technology transitions in the past to project how new transitions could arise in the future.

To do so, he is collaborating with environmental scientists at the Tyndall Centre at the ̽��ֱ�� of East Anglia and at the Open ̽��ֱ��, policy advisors and researchers at the UK Department for Energy and Climate Change and the Committee for Climate Change, and applied economists at Cambridge Econometrics.

Mercure believes that this will be the first time an energy–economy–environment model at the global level simultaneously considers technology diffusion in all sectors of energy use alongside natural resource constraints and the interaction between sectors.

“If the global power sector is to decarbonise by 2050 without there being significant economic costs then all countries must make a contribution to the development of renewable technologies,” he added.

“Take as an example the solar photovoltaic industry. Large investments in Germany enabled production costs of firms in China to decline significantly in recent years, which could not have occurred without such investments. Technology sectors typically face a classic vicious circle: established technologies thrive because they are established, and emerging technologies see barriers to their diffusion due to the lock-in of established technologies. This will be the case unless an emerging technology is a radical improvement over established technologies, or it benefits from strong policy support and investment. This applies to many other sectors such as mobility technologies, industry and household appliances.”

Professor Douglas Crawford-Brown, Director of 4CMR, is excited by the prospects of this new modelling: “Dr Mercure’s work sits nicely at the intersection of aggregated economic sectors and the decisions of individual investors. He is plotting an intermediate ground in which both theories of investor behaviour and empirical econometrics allow for much greater insights into energy supply and demand.”

Mercure’s recent research has focused on the global electricity sector, which currently emits 38% of global fuel combustion emissions mostly through the use of fossil fuels. ̽��ֱ��new project will extend the model to all major energy-consuming sectors, including transport, industry (e.g. steel, cement) and buildings (heating, appliances), to model different scenarios of support policies for technological change.

“We want to be able to answer questions about the impact of policy changes on global emissions. Badly coordinated roadmaps of technological change can lead to increases in GHG emissions and so it’s important to know which types of policies will incentivise efficient emissions reductions in order to avoid dangerous climate change.”

New research seeks to take account of the fast pace at which technology is evolving in understanding how to tackle greenhouse gas emissions.

Technology comes to life through innovation, timely investments and policy incentives

Jean-Francois Mercure

Paul Krueger

Car2Go Electric Car Sharing

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Yes

Cambridge unveils plans to become Retrofit City

tdk25 — Wed, 12 Jun 2013 00:11:27 +0000

A landmark energy-efficiency initiative which aims to reduce the carbon emissions from buildings in Cambridge by 30% before 2050 through a massive, city-wide retrofit scheme, has been launched.

̽��ֱ��Cambridge Retrofit Project will function partly as a social enterprise, and partly as a professional delivery service, and is being run by representatives from organisations and businesses across the East Anglian city.

It has set itself the formidable task of supporting the retrofits of approximately 20,000 private homes, and another 20,000 non-residential properties, before the mid-way point of the 21st century. These will include Victorian terraces, modern shopping centres, and the medieval college buildings of the city’s 804-year-old ̽��ֱ��.

̽��ֱ��aim is to make a decisive contribution to the UK’s carbon reduction target of 80% by 2050 in a single move focused on the energy-efficiency of buildings. In the process, the project will also seek to make Cambridge the first city to hit that national objective. From today, businesses and residents are being urged to sign up through a newly-launched website, www.cambridgeretrofit.org, where a full list of the many organisations already involved can also be found.

“Retrofitting” essentially means adding new technologies and features to a building to increase its energy-efficiency and reduce its energy consumption. In practice, that can involve the introduction of measures such as loft and cavity wall insulation, enhanced window glazing, draught-proofing, energy-efficient lighting and improved boilers. ̽��ֱ��result is reduced energy consumption and carbon emissions, but the programme also aims to build up local businesses, create warmer homes and increase the value of properties.

Making those improvements throughout an entire city – especially one which, like Cambridge, has a daunting range of buildings dating back to the Middle Ages – will require a huge community effort that cuts across public and private sectors.

̽��ֱ��total cost of retrofits over the course of the programme is expected to be £1billion. ̽��ֱ��project team calculate, however, that the energy-savings that result will be worth £1.5billion. ̽��ֱ��environmental payoff will be even greater, – the city’s carbon footprint, currently 830,000 tons of CO2 a year is expected to decrease at a rate of about 1% a year, eventually falling to about 500,000 tons of CO2 per annum as a result of the retrofit programme.

Since 2012, organisations from across Cambridge have been drawing up plans which will enable the project’s leaders to stimulate demand for retrofits, and then bring that together with financial support and delivery services. ̽��ֱ��process has involved local planners, building firms, property managers, housing associations, lawyers, engineers, architects and researchers, as well as national government offices and English Heritage.

̽��ֱ��project will be handled by a Programme Management Unit, which breaks down into three sub-groups. A “Project Support and Aggregation” arm, run by the energy solutions firm, Day One Energy, will oversee the practical business of delivering and financing retrofits. ̽��ֱ��online consultation service, Consense, will lead the process of mobilising businesses and residents. Finally, supporting research and monitoring will be undertaken by the ̽��ֱ�� of Cambridge’s Centre for Climate Change Mitigation Research and its academic partners.

Overseeing this will be a group of 30 public and private sector partners, chaired by the former leader of Cambridge City Council, Sian Reid. This group will be responsible for monitoring the Unit’s performance and ensuring that it is acting in the best interests of the community.

Professor Douglas Crawford-Brown, Director of the Cambridge Centre for Climate Change Mitigation Research, said: “It’s a huge challenge, but if we are going to achieve the ambitious carbon reduction targets that the UK has set, then we are going to have to learn how to run projects of this scale.”

“Crucially, our plan is to ensure that the business of retrofitting Cambridge’s buildings is demand-driven. Other attempts at initiatives like this have tended to work on the assumption that if a programme to make large-scale changes like this is created, people will use it. Our view is that you don’t start supplying until you’ve got the demand. Our first objective is to get big estate-holders involved.”

Residents, companies and public organisations alike can add their details to the website. Using this, retrofits will be co-ordinated by the Programme Management Unit to keep the costs as low as possible, and to ensure that local businesses and innovators form the project’s principal supply chain.

̽��ֱ��initial focus will be on the non-residential sector – the estates of the City and County Councils, property firms, schools, universities and the ̽��ֱ�� of Cambridge Colleges. These organisations are considered prime targets for retrofits because of the cost-saving benefits. “Our approach is that we’re not here to save your soul and we don’t care why you’re doing it, so long as you’re doing what needs to be done,” Crawford-Brown added.

Over time, the project will focus increasingly on the residential sector, working alongside local councils and other organisations to help reduce energy costs in homes.

̽��ֱ��Programme Management Unit will also offer all participants optional support through which they can negotiate the cost of retrofitting their properties. For example, in some cases, the Unit will take out an initial, low-cost loan to pay for the retrofit up front, then gradually pay this back by taking a cut of the profit made through energy-savings over time.

Several inaugural “beacon” projects are now being prepared by the project team, with a view to giving the scheme some initial momentum. They will include at least one college building, one commercial building, a local authority office and a ̽��ֱ�� of Cambridge building.

Sian Reid, chair of the project’s oversight group, said: “It is wonderful to see that many Cambridge organisations have already signed up to Cambridge Retrofit. Getting people involved early, and then constantly broadcasting the successes that are happening in Cambridge, is crucial to the success of Cambridge Retrofit. There is a real opportunity here to create nationwide awareness of how retrofits can work for building owners, occupiers and communities. To do that, we have to make Cambridge a living example of best practice.”

Julian Huppert, MP for Cambridge, said: “Cambridge Retrofit has the exciting possibility of allowing everyone in Cambridge to benefit from more energy-efficient buildings, saving money and helping to protect the environment. I am pleased that so many people and organisations are coming together to make this happen.”

For more information about this story, please contact: Tom Kirk, Office of Communications, ̽��ֱ�� of Cambridge. Tel: +44 (0)1223 332300; Email: thomas.kirk@admin.cam.ac.uk

A new network of public and private sector organisations aims to carry out retrofits across Cambridge, bringing down carbon emissions, cutting energy costs, and helping to make it the first city to meet the UK Climate Change Act carbon reduction target of 80% by 2050.

"We’re not here to save your soul and we don’t care why you’re doing it, so long as you’re doing what needs to be done"

Douglas Crawford-Brown

Cambridge Retrofit

̽��ֱ��wide range of building types in Cambridge, ranging from modern structures to medieval college buildings, make it a natural community in which to test the feasibility of city-wide retrofits to cut carbon emissions.

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Yes

Food security: your questions answered

lw355 — Wed, 31 Aug 2011 15:33:16 +0000

Should I use GM?

I live in Manipur, north eastern India. It’s a hilly area. ̽��ֱ��cropping system is a traditional terrace system and we sow once a year. We grow rice, some indigenous pulses, vegetables and fruit. Most of these crops are sown in the month of June and the rest of the year the land remains dry and unused. Nowadays cropping lands are reducing due to lack of water and growing of unwanted plants in the plot. So, I want to ask what measurement should we take either to adopt GM which we could not afford and is hardly available or should we focus on traditional recovery?

N G Ngashangva, Phadang Village Christian Compound, Manipur, India

Dear Mr Ngashangva, I do not think that there are GM varieties that would be useful to you – at least at present. However if you had herbicide-resistant crops then that might allow you to reduce weeds in your plots. It may also allow you to plant without ploughing or digging up the soil because you could drill holes to plant your herbicide resistant seed and then kill the weeds by herbicide application. Drought resistant GM crops are being developed but they are not available yet.

Professor Sir David Baulcombe

Can we tackle the financialisation of food?

I would like to ask what your analysis is of the impact of speculation in the food derivative markets on food prices. Bodies including the OECD and the G20 agriculture ministers are increasingly recognising the contribution of speculation in commodity derivative markets to food price spikes, which obviously has an immediate and negative impact on consumers everywhere, but especially in developing countries where food security is already a problem. Do you think we can tackle food security for the poorest people in the world without also tackling the financialisation of food globally?

Vicki Lesley, Brighton

̽��ֱ��theory is that food derivatives help farmers to hedge the price risk they face. Demand for food has grown enormously in recent years, not the least with the 'emergence' of the Indian and Chinese economies. ̽��ֱ��supply of food has suffered erratically due to climatic calamities. Food prices have not only risen but have been volatile. Uncertain prospects of future food prices encourage farmers to hoard, and volatile prices stifle investments. Derivatives contracts allow the price risk to be traded so that speculators can take it on, induced of course by some probable return. A farmer who fears that the price of his crop will decline as it grows can hedge the price risk by entering into a futures contract to sell his crop in so many months’ time at a price determined now. This principle of transferring risk from hedgers to speculators is also the basis of option contracts which give holders the right to buy or to sell the commodity at an agreed price on or before a specified future date. If derivatives markets stayed true to principle, they should help in discovering price and encourage farmers to invest in the right crops. That is the theory!

But as markets for food derivatives have grown, large buyers and sellers, attracted by the potential for speculative gains, have come to dominate the market, and physical hedgers are of much less significance. Demand and supply are now driven by speculative investment strategies in which commodities form one asset class in large portfolios.

Does this matter? ̽��ֱ��real price of food rises through changes in real demand and supply. Speculators never take physical delivery of the good. Can demand for futures contracts change real demand and their sales change real supply of food?

̽��ֱ��markets for food and for food derivatives are linked of course. Speculators act upon small events that can potentially create price fluctuations in the real market, and amplify them in the derivatives market. Momentum traders render prices volatile. Volatility in turn drives more speculation. Volatile derivative prices that result can move real food prices when (at least some) farmers take them as signals of real prices in the future, and change their inventories accordingly. ̽��ֱ��risk management and price discovery functions of the derivatives market are ever at risk of being washed out by speculators. More often than not, the tail can wag the dog.

Furthermore, in the globalised world, commodity futures markets in different countries are linked. Returns and volatility spill over from rich country markets to emerging and developing country markets. Even in rich countries, futures contracts and the commodities they represent often do not converge to the same value at contract settlement. So even farmers and producers who do have access to the derivatives market cannot hedge efficiently using futures contracts.

̽��ֱ��lives of large proportions of households in poor and developing economies depend on food prices. I agree with you that the need for the commodities futures market to be regulated more effectively, backed by careful research, is urgent.

Dr Paul Kattuman

How can we protect agricultural lands from urban spread?

I wish to congratulate you on such an innovative initiative to research into the biggest global concern - Food Security. Having been exposed to some of the causes of Global Food Insecurity as a young academic with background training and experience in Human Settlement Planning, I have come to appreciate that, one major challenge to ensuring food security is the invasion of prime agricultural land by residential and other urban land uses. In Ghana for instance, the pace of invasion is so fast that large tracts of fertile lands have suffered from urban expansion and population growth particularly in the peri-urban interface. This has not only resulted in reduced food production but has also taken away the very sources of livelihood derived by residents of peri-urban areas.

Against this background, I wish to know what practical strategies could be adopted within the framework of Spatial Planning to ensure that agricultural lands are protected as a basic prerequisite to ensuring food security. Secondly, I will be glad if the group could expound on how a good balance can be achieved between efforts by national and international communities to reverse deforestation and the provision of suitable land for food production as well as the sustenance of rural livelihoods.

Ransford Antwi Acheampong, Kwame Nkrumah ̽��ֱ�� of Science and Technology, Ghana

Thank you for these excellent questions. Although I am not an expert on spatial planning, my research deals with reconciling conflicting priorities for land, and as part of that work I spent a year in the forest zone of Ghana in 2006/2007.

Planners must consider a range of valid objectives (such as requirements for housing, commercial facilities, transport infrastructure, crop cultivation and biodiversity conservation) and attempt to find compromises between them to guide development without being overly prescriptive. To do this, a good place to start is in establishing very clearly what those objectives are, over an appropriate time horizon, by involving interested parties in a consultative process. Local plans need to be coherent with national policies, and national policies need to take account of local needs and constraints. If a particular group is excluded, there will be problems. For example, if only the needs of urban residents and businesses are considered in plans for urban expansion, and not those of peri-urban farmers (or of those who buy and eat the food they produce), any spatial plan will be built on a flawed foundation.

There is also a need for good information to inform decisions about zoning land for different uses. Here, communication and data-sharing between institutions is crucial. Which areas of land are most suitable for crop cultivation? Ghana has a Soils Research Institute which has produced detailed maps of crop suitability, but when I visited the country these were not accessible to planners. Which areas of land are most important for biodiversity conservation? Ghana has tropical forests internationally renowned for their diverse and endemic species, but while staff of the Forestry Commission might know this, many of those working within the Ministry of Food and Agriculture may not. These problems are not unique to Ghana: often here in the UK there is also poor communication between government departments.

How best to conserve forests while producing more food? My research in Ghana has persuaded me that the most promising approach is to grow more food on less land, while protecting (and in the long term, restoring) forests. Measures to increase food output while reducing food production can help too, such as reducing the amount of food that spoils before it can get to market. Increasing yields on existing farmland, while minimising pollution and other problems, will need the intensive application of both scientific knowledge and farmers’ knowledge. There is a role for planners here in synthesising information about the most appropriate lands for crop production (with good soils, low carbon storage and low biodiversity value) and directing agricultural development towards those areas.

In addition to targeting agricultural development towards existing croplands with the most potential, reducing deforestation will require zoning of land where further agricultural development is inappropriate. In Ghana, this might include all of the remaining high forests, many wetland areas, plus areas with potential for restoration, such as land dominated by shaded cocoa farms. Careful screening and regulation of any large-scale land acquisitions, particularly for biofuel crop cultivation, will be needed to ensure that they deliver real benefits for the nation and for local people, without damaging areas of high conservation value. Oil palm companies in Ghana have adopted a set of Principles and Criteria for responsible palm oil cultivation. Similar principles could be used to ensure that development of other crops, too, adheres to strict environmental and social safeguards.

Dr Ben Phalan

Should we instead address global overpopulation?

Thomas Malthus wrote. "Must it not then be acknowledged by an attentive examiner of the histories of mankind, that in every age and in every State in which man has existed, or does now exist, that the increase of population is necessarily limited by the means of subsistence, that population does invariably increase when the means of subsistence increase, and, that the superior power of population is repressed, and the actual population kept equal to the means of subsistence, by misery and vice."

While not suggesting we do nothing and thereby cause misery and vice, by working to produce more food for a growing population, are we not just compounding the problem because it will enable the population to grow even bigger, requiring even more food, and at the same time having an even greater negative impact on our planet? Why not address the root of the problem, ie global overpopulation, by better education, financial incentives from government, and other means to encourage people to have less children and therefore reduce the population back to a level that is naturally sustainable on Earth?

Jacqueline Garget, Cambridge

̽��ֱ��term ‘overpopulation’ makes a normative claim about population size, so we might begin to answer your question by first positing another one: what constitutes an ‘ideal’ or ‘naturally sustainable’ population?

A few statistics might help us frame this discussion. According to the United Nations, Somalia, Sudan, and Mozambique, three African countries severely affected by hunger and malnutrition, have between 14 to 29 inhabitants per sq km. These figures contrast sharply with 400 people per sq km for the Netherlands, 351 for Belgium, and 255 for the UK. Ghana, which is twice the size of the UK, has nearly a third of the population of the latter. Yet, we are unaccustomed to thinking of the UK or Belgium as ‘overpopulated.’ Why? Well, clearly the long-term carry-capacity of an area, rather than the overall population density, is what matters most. But that point aside, I do not think that one needs to delve too deeply to see that the tendency to single out the developing world for attention expresses a deep and abiding fear of the other. We all know that we would need several additional planet Earths if everyone adopted the consumption patterns of the average America; and yet that knowledge does not tend to diminish the perception that it is ‘their’ prolificacy that threatens ‘our’ existence. Historian David Arnold puts this very well when he writes that ‘too many people’ usually means ‘too many of the wrong sorts of people.’

Of course, Malthus’s own account of the population problem was saturated in this kind of moral reasoning. ̽��ֱ��poor, especially the non-European poor, were creatures of nature that bred without any consideration of the consequences. Malthus believed that in the ‘southern climates’, where virtue was absent and the inhabitants lived in a ‘degraded state’, the perennial threat of war, pestilence and famine was necessary to sharpen faculties, force improvements, and prevent additional population increases. ̽��ֱ��‘four horsemen of the apocalypse’ were thus seen as a ‘positive check’ on human improvidence – a last resort to discipline the intractable and restore balance in the human and natural world.

̽��ֱ��latent racism of Malthus’ worldview is frequently ignored. Instead arguments tend to concentrate on his more general point that famines are caused by a decline in food availability brought on by an increase in human numbers. We might ask, then, if this is a helpful way to think about the aetiology of subsistence crises?

Unfortunately, measuring aggregate food supply against population totals – as Malthus did – is profoundly misleading, because it gives little consideration to the ways in which resources are unequally apportioned. This is one of the major contributions of Amartya Sen’s classic work on famines as ‘entitlement failures’ (Sen’s book, Poverty and Famines: An Essay on Entitlement and Deprivation, was first published in 1981). According to Sen, people starve when either their ‘endowments’ (by which he means their resources) or their ‘entitlement set’ (by which Sen means the bundle of goods and services that a person can legally utilise) change to such a degree that they can no longer obtain adequate sustenance.

Sen offers many examples to think about how shifts in resources and entitlements can lead to starvation. For example, a farmer and his family may starve because they find themselves unable to pay rent and are forced of the land. Alternatively they may starve or undergo severe hardship because the cost of labour or price of inputs (for, say, seeds and fertilisers) increases to such a degree that they are unable to undertake the usual cultivation the land. ̽��ֱ��point is that people ‘command’ food through a variety of mechanisms, and thus analysing the ‘entitlement set’ is much broader than looking only at, say, income or indeed food supply, as the determining factor in precipitating a subsistence crisis.

I spend some time discussing Sen’s Nobel Prize winning research because it demonstrates how the ‘famine question’ involves so much more than the ‘population question’. Or as Sen has put it himself, ‘the most important denial made by the entitlement approach is ... the simple analysis in terms of ‘too many people, too little food.’ ̽��ֱ��Malthusian ‘food availability decline’ model, as Sen calls it, presupposes that starvation deaths result from a severe interruption in the supply of food (caused by an environmental catastrophe, like a drought, or arising from the effects of overpopulation), whereas the ‘entitlement’ approach focuses attention on the allocation of resources within a market-based economy.

I find the latter approach to be a more helpful method to analyse the problem of global hunger. It is a well-established fact that there is enough food to feed the world’s present population – indeed by some estimates there is 20% more food than the world currently needs. Yet hunger persists and future famines seem very likely. I would suggest that the problem is less the number of people, than a particular kind of political economy that places food in some hands and not others.

Dr David Nally

How do we reclaim nutrients from water?

How long have we got to develop massive systems of nutrient reclamation from the world's sewers (before phosphate or potassium, or perhaps boron becomes limiting) and how much energy might such a system, require - energy that has to be added to our energy budget for the future? Agriculture exports nutrients to the cities of the world with every tonne of food supplied. Until mankind finds ways of returning those nutrients to the cropland (instead of flushing them out to sea) no system of farming can be described as sustainable. There is an added challenge here: we need those nutrients returned, but without the pollution that the cities inevitably mix with them - particularly heavy metal contamination.

Bruce Danckwerts, Choma, Zambia

Many of the world's larger communities are exploring the option of nutrient recovery, although often in the context of recovering the energy content of the organic matter in sewerage. For example the city of San Diego in California is producing such as system, in part in response to recovering energy content and in part to recover the water. Nutrient recovery has tended to be a side benefit. You are, however, correct that nutrient recovery will become increasingly important in the future, not only because the raw materials of nutrients are being depleted, but because the energy required to make these into useful materials such as fertilisers is quite large, and so contributes to the greenhouse gas emissions of nations.

Dr Douglas Crawford-Brown

Can we afford the energy input? Do we have adequate water resources?

Someone once said that modern agriculture is the conversion of fossil fuel calories into edible calories, due to the reliance on mechanisation. If oil prices continue to rise as predicted, the cost of farming will increase markedly, as will the cost of the food produced. Since it seems we can no longer control oil prices in a sustainable fashion, except by recession, it would appear that permanent food price rises are now a reality. How can we give people access to affordable food when we rely so heavily on expensive fossil fuel to produce it? Also, we know that water tables in the Middle East, China and Australia are already severely depleted, mainly due to the demands of agriculture. If this issue turns out to be more widespread, how on earth can we expand agriculture further?

Tristan Collier, Cambridge

Your comments are right on the mark. In fact, the Foreseer Project we are involved in aims to study the physical linkages between energy, agriculture and water resources to inform discussions like this on a local, regional and global level. ̽��ֱ��aim of the project is to develop an online visualisation tool to help the policy makers, industry and the general public understand the importance of future resources such as energy, land and water.

̽��ֱ��major physical linkages between food production and energy occur through the production and use of fertiliser (which uses about 2% of world energy production) and the use of fossil fuels for mechanisation of food production and transportation of food. Decreasing this physical reliance might make food prices less linked to energy prices. One possible strategy to do this would be to avoid the use of excess fertilisers.

Agricultural yields in developing countries could potentially increase without adding much mechanisation, fertilisation and irrigation. Yields and productivity can be improved by better informing the local farmers about the use of new practices, such as agro-forestry and soil moisture conservation practices, including minimum tillage, depending on local conditions.

Water scarcity is probably the biggest limitation to expansion of agricultural production, as you correctly point out. There is some room for improvement, such as better irrigation technologies, rainwater harvesting and increase use of wastewater in agriculture production. However we agree that agricultural production cannot be expanded infinitely. Using desalinated water is also an option, though today it is still much too expensive to be used for irrigation – and it comes at energy price. One of the main goals of ̽��ֱ��Foreseer tool is to include this kind of energy, water and land interactions into the analysis.

Grant Kopec, Bojana Bajzelj and Liz Curmi

Is GM the answer?

How can GM technologies serve enough food for the human population which is growing rapidly every year and if we compare with sosiocultural aspect of human, poverty and planting areas? Maybe we can increase the quality and quantity of food with genetically modified food, but it can’t compare with population growth. I come from Indonesia, most people said my country is a high biodiversity country, evergreen and we can grow up every vegetable and rice, but it can serve for Indonesian (for about 200 million people), there are many malnutrition children, hungeroedema and etc. What do you think about the connection between population growth, poverty and quantity of foods?

Rikhsan Kurniatuhadi, ̽��ֱ�� of Tanjungpura, Pontianak City, Indonesia

To feed the growing population we will likely need a whole array of approaches. This will include, but will not be limited to strategies like traditional breeding, enhanced breeding strategies (including making use of genetic information that is not currently residing in the genepool of the crop in question), as well as improvements in engineering aspects of agriculture, and the supply chain itself. All of these areas have the potential to be important. Whether any one part of the process, including genetic modification, is the most important will only be clear when we look back.

However, there are traits that one could engineer into crops to improve tolerance to stresses, including pest and pathogen attack. There are also the approaches currently being taken to improve nutrition of crops. There is also the possibility of using natural variation in photosynthesis to increase the potential yield of crops. There is growing support for the argument that, to maintain biodiversity, we need to ensure the agricultural land that is in use is used as efficiently as possible. ̽��ֱ��hope is that multiple technologies will be combined and this will contribute to sustainable food production in the future.

Dr Julian Hibberd

And finally….

Watch out for the following events at the ̽��ֱ�� of Cambridge’s Festival of Ideas:

Is the future of food GM?

Saturday 22 October 3.30pm – 4.30pm, Faculty of Law, Sidgwick Site

What are the challenges and solutions to the global food crisis? Are genetically modified crops a natural progression in efficient agriculture or are we playing God with nature?

Can we afford not to embrace GM? Join Professor Sir David Baulcombe, Regius Professor of Botany; Tony Juniper, Sustainability Adviser; David Nally, Department of Geography and the chair, Jack Stilgoe, ̽��ֱ�� of Exeter for the debate.

Seven billion: the crowded planet

Tuesday 25 October, 6pm – 7pm, Mill Lane Lecture Rooms, 8 Mill Lane

̽��ֱ��world’s population will reach seven billion this year. Can the Earth sustain this many people and is reproductive freedom a fundamental liberty? What will the future hold for a crowded planet? Panel discussion with Professor John Guillebaud, Population Matters; Sara Parkin, Forum for the Future; Dr Rachel Murphy, ̽��ֱ�� of Oxford; Fred Pearce, author of Peoplequake and the chair, Sir Tony Wrigley, Cambridge Group for the History of Population and Social Structure.

Energy policy: should scientists be in charge?

Thursday 27 October, 5.30pm – 6.30pm, Judge Business School, Trumpington Street

̽��ֱ��Electricity Policy Research Group lift the lid on the long-standing dispute between engineers and economists. Who knows best and whose contributions should be used to solve the problems of energy usage in the UK today?

For more information about these and many other events, please visit www.cam.ac.uk/festivalofideas

Over the past month, the ̽��ֱ�� of Cambridge has been profiling research that addresses one of the biggest challenges of the 21st century – how to guarantee enough food, fairly, for the world’s rapidly expanding population. As part of this, we asked whether you had a question that you wanted us to answer, and put them to a panel of academics who specialise in research to do with food security. Here's what they had to say. Thanks to everyone who sent questions in!

I would suggest that the problem is less the number of people, than a particular kind of political economy that presents some people as a liability to the welfare of others.

David Nally

Adactio on Flickr

Vegetables

Panel contributors

Professor Sir David Baulcombe

Sir David Baulcombe is Regius Professor of Botany, a Royal Society Research Professor and Head of the Department of Plant Sciences. His research interests include genetic regulation, disease resistance and gene silencing; he discovered small interfering RNA and the importance of this molecule in epigenetics and in defence against viruses. In 2008, he chaired a Royal Society Working Group on how biological approaches can enhance global food crop production. In 2009, he was knighted by Queen Elizabeth II for services to plant science.

Dr Douglas Crawford-Brown

Douglas Crawford-Brown is Executive Director of the Cambridge Centre for Climate Change Mitigation Research in the Department of Land Economy. He is interested in all aspects of research related to the development of policies for mitigating the risks of environmental change, including - but not restricted to - climate change, and has provided expertise to government bodies and businesses.

Dr Julian Hibberd

Julian Hibberd is a plant scientist in the Department of Plant Sciences. His research interests lie in the evolution and assembly of photosynthetic apparatus in plants. In 2008, he was named by Nature magazine as one of ‘Five crop researchers who could change the world’ for his research, which would greatly increase the efficiency of photosynthesis and create a rice cultivar that could ‘have 50% more yield’.

Dr Paul Kattuman

Paul Kattuman is a Reader in Economics at Cambridge Judge Business School and Director of Studies in Economics and a Fellow of Corpus Christi College. Dr Kattuman’s research interests include: applied econometrics and statistics; industrial organisation; distribution dynamics methods and applications; online markets; the software industry; co-operative game theory applications; system dynamics; India. He is a member of the Business & Management Economics subject group at Cambridge Judge Business School and is on the editorial board of the B.E. Journal of Economic Analysis & Policy. Prior to beginning his academic career, he was an economist in the Indian civil service.

Dr David Nally

David Nally is political geographer in the Department of Geography. His research focuses on the relationship between famine and society and the politics of disaster relief, as well as the historical origins of development geographies and theories of political violence. Nally has also worked on the political economy of agro-biotechnologies. His latest book Human Encumbrances: Political Violence and the Great Irish Famine (2011) traces the causes of the Irish Famine of 1845-50.

Dr Ben Phalan

Ben Phalan is a conservation biologist in the Department of Zoology and a junior research fellow at Churchill College. His current research is concerned mainly with understanding the impacts of agriculture on tropical faunas and identifying land use strategies to minimise those impacts. He works in collaboration with BirdLife International, the RSPB and the UNEP World Conservation Monitoring Centre.

Grant Kopec, Bojana Bajzelj, Liz Curmi

Grant Kopec, Bojana Bajzelj and Liz Curmi are researchers on the ̽��ֱ�� of Cambridge's Foreseer Project, a cross-departmental project which examines current and future interactions between the supply and demand of regional energy, land and water resources. Collectively, they have expertise in water economics, energy systems, land-use issues and climate change mitigation.

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Yes

Placing water into the picture for climate change

bjb42 — Mon, 22 Aug 2011 09:34:35 +0000

In the United Nations Framework Convention on Climate Change negotiations in Copenhagen and Cancun, both mitigation (preventing climate change) and adaptation (responding to the increased risks of climate change) measures were on the table, but there was little mention of water. There is an understandable desire to focus on the core task of reducing greenhouse gases, but this must not be at the expense of ignoring the changes in water availability and quality that will accompany climate change. For the majority of people in the world, especially the poorest, water remains the most significant environmental and public health problem.

̽��ֱ��lack of consideration of improved water provision as a way of reducing greenhouse gas emissions is understandable since the use of water usually accounts for only a few percent of the carbon footprint of most nations. There are exceptions to this rule; for example, for some countries in the Middle East treating and pumping water contribute as much as 30% of their energy use. But overall, a focus on water is not an effective way to get at mitigation.

For adaptation, the situation is starkly different. Water is arguably the most significant problem facing nations as a result of climate change; even if climate change were not occur, it is a global challenge to provide safe, plentiful, reliable and affordable water, especially as populations grow towards 9 billion. Sea level rise will affect communities world-wide, with some of the most dramatic effects being seen in the Lesser Developed Countries and Small Island Developing States that are the focus of international climate change efforts. Changing patterns of rainfall will bring increased drought or flooding to even the developed nations, with impacts on sustainable development and food security. Potential changes in the amount and quality of water are therefore at the heart of adaptation strategies, and leaving them off the table is a missed opportunity.

̽��ֱ��world needs an aggressive international campaign of water-related adaptation measures, allocating resources where the risks are highest. This requires significant improvements in understanding how climate change risks will appear over time, and what management strategies can reduce these risks in the most cost effective, appropriate and equitable ways. This in turn requires improving the evidence base through advanced research such as that carried at the ̽��ֱ�� of Cambridge in regard to:

Supporting the scientific capacity to quickly identify storms that will bring flooding, and to evacuate effectively
Protecting the processes of wastewater treatment so extreme weather events aren’t followed by outbreaks of microbial disease
Developing drought-resistant crops
Enhancing the ability of land to capture and store water, both to prevent flooding and to reduce evaporation back to the atmosphere
Developing public health systems capable of identifying water-borne disease outbreaks in their early stages, and provide adequate health care
Identifying strategies of sea wall defenses, and perhaps relocation, for communities in coastal regions affected by sea level rise
Strengthening planning regulations to prevent further development in areas vulnerable to flooding and inundation by the sea

All of these are adaptation strategies that reduce the risks from climate change, and do so through a focus on water and its changing availability.

International negotiations hopefully will produce a framework for reducing the risk of climate change in the face of significant uncertainties as to timing and extent of that risk. A large part of the solution will be rapid and significant reduction in global emissions of greenhouse gases, and so that issue should be given pride of place in negotiations. This cannot, however, be at the expense of ignoring the central role of water in risk reduction. It is often said that mitigation is about air, adaptation is about water. ̽��ֱ��scientific, technological, behavioural, organisational and political innovations to produce effective adaptation strategies focused on water need international support, backed by a sound base of evidence that will ensure we tackle the right problems in the appropriate places with appropriate technologies and policies. That is a grand challenge for researchers in the 21^st century.

Dr Douglas Crawford-Brown is Executive Director, Cambridge Centre for Climate Change Mitigation Research, based within the Department of Land Economy, ̽��ֱ�� of Cambridge.

As World Water Week, an annual week-long global conference on water provision and sustainability, begins in Stockholm, Dr Douglas Crawford-Brown explains how the world needs to prepare for the consequences climate change is likely to have on people's access to this vital resource.

̽��ֱ��world needs an aggressive international campaign of water-related adaptation measures, allocating resources where the risks are highest.

Douglas Crawford-Brown

̽��ֱ�� of Cambridge Office of Communications.

Douglas Crawford-Brown.

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Yes

Safe water solutions

lw355 — Mon, 01 Nov 2010 15:38:27 +0000

Almost 900 million people worldwide lack access to safe water; polluted lakes and waterways diminish livelihoods and health; and 2.6 billion people (almost half the population of the developing world) lack access to adequate sanitation¹ .

In Cambridge, research groups from several disciplines are working in regions worldwide where dirty, polluted and inadequate supplies of water make drinking, cooking and cleaning an everyday challenge for the communities who live there. We take a look here at some of their solutions.

Water cleaning with mussel power

Zoologist Dr David Aldridge is a keen advocate for the amazing abilities of mussels to clean up water. His work in China is using these remarkable organisms as cheap and sustainable water filters to improve water quality and, as a result, it is hoped that a local industry will develop to farm them.

China’s Lake Dianchi was once a rich haven of aquatic species but increasing levels of pollution from a cocktail of fertilizer run-off, sewage and the effluent from factories has caused a huge deterioration in water quality. ̽��ֱ��water is undrinkable and a hazard to those using it for washing, and the native aquatic wildlife has all but died off. Where once underwater visibility was over 10 metres, on a good day it’s now a mere 30 cm.

Using a set-up that could be replicated in many of the world’s polluted freshwaters, Dr Aldridge from Cambridge’s Department of Zoology and colleagues at the Chinese Academy of Sciences have deployed specially bred giant mussels – once native to the lake – in experimental enclosures along the lakeside.

̽��ֱ��mussels filter 50 litres of water a day, removing algae and suspended particles. ‘In just a few months,’ he explains, ‘not only did the water become clearer but native plants suddenly began to emerge from seeds buried for decades on the lake bed. These, in turn, provide habitat for insects, and then fish, and the system stabilises back to clearer water.’

One challenge has been the tendency of people living locally to eat the mussels. ̽��ֱ��team’s solution has been to turn to pearl farming to encourage the community to sustain the mussels in the lake. Chopsticks are used to insert a tiny bead of shell into the mussel, around which a pearl is formed. Recognising the potential impact of this idea on bolstering local industries, the World Bank awarded Dr Aldridge a Development Market Place Award to continue the work.

Dr Aldridge is also developing a means by which local authorities and managers of waterways can check the health of freshwater in their region, reducing the need for difficult and costly chemical testing. ‘We’re using the biology of the lake as an indicator of water quality. ̽��ֱ��number and type of organisms, or biotic index, provides a useful indication of the state of the water they live in. ̽��ֱ��guide book we are creating will enable users armed with only a hand net to monitor the condition of water in their province.’

Healthy water for households

Many people who lack access to safe water live in regions where conventional methods for supplying drinking water through water pipes are simply not possible or cost-effective. For these people, the alternative is to use household water treatment and safe storage systems (HWTS) based on chlorination, solar disinfection, ceramic filters or biosand filters.

As part of Dr Douglas Crawford-Brown’s wide research interests in water policy, he has been examining the effectiveness of reducing microbes in drinking water using low-cost HWTS in the developing world. As Executive Director of the Cambridge Centre for Climate Change Mitigation Research, in the Department of Land Economy, his research interests have an environmental perspective: ‘ ̽��ֱ��problem of ensuring safe water provision in the face of environmental change is a global one. But for developing countries, where large investments in infrastructure are not possible, it’s a massive concern.’

His work has been in collaboration with colleagues Dr Mark Sobsey and Dr Linda Venzcel at the ̽��ֱ�� of North Carolina, from which he moved two years ago, and Dr Christine Stauber at Georgia State ̽��ֱ��. Dr Crawford-Brown’s role in the long-term project has been to model the predicted human health impacts so that they can be compared against field epidemiological data in the Dominican Republic, Ghana, Honduras and Cambodia.

‘Our results show clearly that there is significant reduction in microbes, but also a residual concentration that can be quite difficult to remove,’ he explains. ‘In one project funded by the International Rotarians, we found that a simple sand filtration HWTS in the Dominican Republic halved the incidence of diarrhoeal disease, a major cause of death among infants in poor communities worldwide.’

Given that affordability of water systems is a critical regulatory issue, his research has also looked more widely at health–health trade-offs. ‘Trade-offs occur when the costs of water treatment in poor communities cause them to re-allocate limited finances, often away from buying medicine, unless public programmes are brought in to provide healthcare. Our goal is to provide policy makers with the evidence on which to base decisions on risk and in allocating budgets.’

Improving outcomes

Having worked for several years in rural Nepal trying to implement the use of water filtration units, Tommy Ngai from the Department of Engineering knows only too well that, despite their benefits, the adoption and continued use of HWTS is not always straightforward.

For the past four years he has been investigating how to scale up the dissemination of HWTS. Working with Dr Dick Fenner in the Centre for Sustainable Development in the Department of Engineering, his research has taken him to Nepal, southern India and Ghana, where he has carried out extensive interviews with project management staff, community workers, government officials, shopkeepers and household end users.

‘It’s not uncommon for communities either to not take up HWTS or for the equipment to be found lying abandoned a year or so later,’ he explains. ‘There may be a lack of awareness among potential users, or the devices may be too expensive to operate and maintain, or the supply chain unavailable, or there may be technical difficulties and ineffective post-implementation support.’

Ngai’s research has, for the first time, captured the big picture of the many competing factors at play – from the technical and financial, to the social and institutional. ̽��ֱ��outcomes are three programme-specific computer simulation models linking over 300 different variables. ̽��ֱ��models can help implementing organisations to appreciate the complexity of project management, to understand the interactions and consequences of any policy strategy and, crucially, to make recommendations for increasing the success of an HWTS programme.

‘Literally thousands of scenarios can be simulated in the model, whereas in the real world you can only try one strategy at a time,’ he says. ‘Comprehensive analysis showed that no single strategy will always work in all situations, and that some measures that have long-term benefits may at first appear counter-intuitive.’

One of the models has also been designed as an easy-to-use simulation game that can be run on a PC, allowing agencies and government officials to explore the effects of different potential intervention strategies concerning programme expansion, promotion, training, pricing and capacity building, and to predict adoption and sustained use of HWTS.

In his next post, as Director of Research Learnings at the Centre for Affordable Water and Sanitation Technology in Canada (www.cawst.org/), Ngai will be using his research to help NGOs and government policy makers to understand quickly how best to encourage sustained adoption of HWTS in their region.

^{1 www.unep.org/pdf/SickWater_screen.pdf}

For more information about these projects, please contact Dr David Aldridge (da113@cam.ac.uk) at the Department of Zoology; Dr Douglas Crawford-Brown (djc77@cam.ac.uk) at the Department of Land Economy; Tommy Ngai (tommyngai@yahoo.ca) and Dr Dick Fenner (raf37@cam.ac.uk) at the Department of Engineering.

Research across the ̽��ֱ�� is helping to clean up water in regions around the world.

̽��ֱ��problem of ensuring safe water provision in the face of environmental change is a global one. But for developing countries, where large investments in infrastructure are not possible, it’s a massive concern.

Dr Douglas Crawford-Brown

Tommy Ngai

Water clarity improvement after filtration

Sanitation innovation

Ensuring access to safe water isn’t the only challenge; it’s also what you do with waste. An innovative study has come up with a prototype system that could improve sanitation in urban slums.

̽��ֱ��realities of high-density living in urban slums have made conventional approaches to improved sanitation practically impossible, with low-income families renting living space in tightly packed, unplanned settlements serviced by pit latrines.
Nate Sharpe’s research in the Centre for Sustainable Development has come up with a solution for emptying pit latrines in the slums of Dar es Salaam, Tanzania, although his findings should be applicable to many other similar cities around the world. ‘Pit latrines are filling up faster than ever and people are often forced to rely on unhygienic emptying methods,’ he explains. ‘If smaller amounts of the sludge could be removed more often, it becomes easy to transport – even on the back of a bicycle.’

Sharpe has designed a prototype bicycle-powered vacuum pump/tank system and a business model for small businesses to run a latrine-emptying service at a low enough price that even the poorest might be able to afford to make their latrine usable again. ̽��ֱ��next stage is to test the device in Tanzania and to put the device into production.

His research was completed as part of an MPhil in Engineering for Sustainable Development with Dr Heather Cruickshank, and is just one of around 35 similar projects annually that are finding innovative engineering solutions to a host of sustainability problems. Many focus on developing countries where, as Sharpe has highlighted, sometimes the solution lies not in the development of new technology but in the creation of a new business angle that works in the local community.

For more information about these and other projects, please contact Dr Heather Cruickshank (hjc34 AT cam DOT ac DOT uk).

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Yes