Sustainablog

This blog will cover some news items related to Sustainability: Corporate Social Responsibility, Stewardship, Environmental management, etc.

13.2.08

Global Warming and the Minefield of Unintended Consequences: whether biofuels emit more or less CO2 than gasoline depends on what the land they were grown on was previously used for


February 13, 2008,  2:05 pm
Global Warming and the Minefield of Unintended Consequences

By Melissa Lafsky

Dubner and Levitt recently wrote a column discussing the unintended consequences of legislation intended to help the neediest segments of society.

Few movements for change have met with as many unintended consequences as the efforts, both in the public and private sector, to combat global warming. Take biofuels (another topic Dubner has addressed here and here). Hailed as the darling of the alternative fuel market, this new energy source, led by the most popular form, ethanol, was declared the solution to burning fossil fuels in 2006. It has since been embraced by companies from luxury car makers to airlines. To meet the growing demand for ethanol, U.S. farmers and agribusiness firms invested millions in growing corn (a move that has already come back to bite them financially). Biofuels have become such a staple of international plans to combat climate change, reports the Times, that governments are even legislating and subsidizing their use:

The EU has mandated that countries use 5.75 percent biofuel for transport by the end of 2008. In the United States, a proposed energy package would require that 15 percent of all transport fuels be made from biofuel by 2022. To reach these goals, biofuels production is heavily subsidized at many levels on both continents.

Fantastic! A worldwide movement to cut emissions and halt what a growing number of scientists call a massive global crisis. Except it all hit a roadblock last week, when two newly-released studies reported that the net environmental effect of using biofuels may be even more harmful than burning the gasoline they were created to replace.

The first study, led by Princeton University environment and economics researcher Timothy Searchinger, found that replacing fossil fuels with corn-based ethanol could actually double greenhouse gas emissions for the next thirty years. As Scientific American writer David Biello explains it:

"Prior analyses made an accounting error," says [Searchinger]. … "There is a huge imbalance between the carbon lost by plowing up a hectare [2.47 acres] of forest or grassland from the benefit you get from biofuels."

Growing plants store carbon in their roots, shoots and leaves. As a result, the world's plants and the soil in which they grow contain nearly three times as much carbon as the entire atmosphere. …

By turning crops such as corn, sugarcane and palm oil into biofuels — whether ethanol, biodiesel, or something else — proponents hope to reap the benefits of the carbon soaked up as the plants grow to offset the carbon dioxide (CO2) emitted when the resulting fuel is burned. But whether biofuels emit more or less CO2 than gasoline depends on what the land they were grown on was previously used for…

The second study, led by Joseph Fargione, a scientist at the Nature Conservancy, found that by switching to biofuels, we could essentially be worsening climate change for the next 93 years, in that "[t]he clearance of grassland releases 93 times the amount of greenhouse gas that would be saved by the fuel made annually on that land," according to the Times. Not to mention the fact that, by switching to growing corn, U.S. farmers have turned away from growing other crops, such as soy. As a result, Fargione told the Times, "'Brazilian farmers are planting more of the world's soybeans — and they're deforesting the Amazon to do it.'"

So in a matter of days, biofuels go from a celebrated fossil fuels alternative to a rainforest-killing disaster, with scientists already calling for government reform on biofuel policies. If anything, this provides a window into how little we actually know about this issue, and the wide lengths left to go in reaching a viable solution.

12.2.08

Self-Generated Energy- Power from the People: Now you can recharge things just by walking around


Thanks to Scot

Self-generated energy
Power from the people

Feb 7th 2008
From The Economist print edition,

Link:  http://www.economist.com/science/displaystory.cfm?story_id=10640707
Now you can recharge things just by walking around

Illustration by David Simonds

IN THE early 1990s, an inventor called Trevor Baylis came up with an idea that provoked the sort of smirking disbelief journalists usually reserve for those who have spent too long in their garden sheds. But the smirkers were wrong. Mr Baylis's clockwork radio turned out to be a great success in places where batteries are expensive and mains electricity is non-existent. In the latest versions, the crank charges a battery directly, rather than winding up a spring which then turns a small dynamo. A few minutes' handle-turning can provide an hour's reception.

Wind-up radios have turned into consumer products in rich countries too, along with wind-up torches, wind-up mobile-phone chargers and wind-up music players. But all these gadgets rely on people having to do some specific work in return for their entertainment. Hence the appeal of finding a way of extracting power from everyday activities without the user noticing what was going on—rather like an old-fashioned self-winding watch, but on a grander scale. There have been several attempts to do this in the past, from trainers that absorb power from the pounding of a foot on a pavement to backpacks that generate it from the bobbing motion of the load while the wearer walks. None, though, has really taken off. But the latest idea might, as it is a human version of a popular idea in car design—regenerative braking.

The "energy harvester" that Max Donelan of Simon Fraser University and his colleagues describe in this week's Science looks like an orthopaedic knee-brace. It tucks behind its wearer's knee and has extensions that strap around the front of his calf and his thigh. When the wearer walks, the knee's motion drives a set of gears which turn a small generator.

On the face of it, that sounds like a recipe for making walking difficult. Surprisingly, it is not. Although the leg muscles perform "positive" work when they accelerate the leg forward to begin a step, when the leg straightens at the end of the step they perform "negative" work as they slow the leg down. If the generator in the harvester were connected during the accelerating phase the process would, indeed, be expected to increase the load on the muscles. But if it were connected only during the decelerating phase it would impose no load. It might even make things easier.

To test this idea, Dr Donelan recruited six volunteers, attached harvesters to their knees and put them on a treadmill. With the generators in the harvesters engaged all the time, walking produced seven watts of power. When the generators were engaged only during deceleration, however, they produced almost five watts (enough to power ten mobile phones simultaneously). Moreover, in that second case, the amount of extra energy used by walkers wearing the harvesters was insignificant, since the harvesters were absorbing energy that would otherwise be dissipated as heat—which is exactly the principle used by regenerative braking in a petrol-electric hybrid car.

One use for the harvesters, if they could be made cheaply (and people could be persuaded to wear them routinely), would be to charge up batteries. But Dr Donelan also has more sophisticated applications in mind. He thinks energy harvesters could be used to power robotic artificial joints and might even, one day, be implanted within muscles for that purpose.

A green light

Even the quotidian uses of an energy harvester like Dr Donelan's will, however, be enhanced by other advances in the field. Rechargeable batteries are getting smaller, lighter and more powerful. They may eventually be replaced in some applications by ultracapacitors that can charge up and discharge even faster than a battery. More efficient cranking systems and generators are also under development. And the miniaturisation of electronics continues to reduce power demands.

One of the biggest changes has been the use of light-emitting diodes (LEDs). This has transformed wind-up lighting products, says Rory Stear, chairman of Freeplay Energy, which specialises in such "self-powered" devices. The company's Indigo lantern, for instance, can provide up to two hours of light from just one minute of winding. LEDs also last for a long time: those in the Indigo are rated for 100,000 hours, whereas a filament bulb might burn out after 16 hours.

Such products can make a huge difference to power-starved people. Freeplay's charitable foundation reckons that the use of kerosene, candles and firewood for lighting absorbs 10-15% of monthly household incomes in sub-Saharan Africa. It is planning to test a range of wind-up LED lanterns in Kenya and South Africa this year. These, it hopes, will allow people to do things like studying at night, increasing their security and coping better with medical emergencies. Freeplay Energy is also developing self-powered medical equipment, including a fetal-heart monitor.

Mr Stear says people in poor countries are prepared to work hard for their energy, with wind-up lanterns often passed among family members to help power them. That bodes well for Dr Donelan's idea, if it can be mass-produced. But the ability of such devices to save on batteries and to serve as reliable standby devices could make them popular even in Western markets as their performance gets better. Save the planet by walking to work and powering up your iPod at the same time. What more could a Green want?

Back to top ^^

"Our servers are using too much electricity, we need to virtualize"


11.2.08

Green work at Microsoft Research: Understanding the earth’s life support systems, and predicting and mitigating the rapid changes that are occurring in these systems because of human activities is one of the great global scientific challenges humanity is currently facing. The programme in ecological and environmental sciences aims to contribute to meeting this challenge


Thanks to Lloyd for the pointer

http://research.microsoft.com/ero/biosciences/compecology.aspx




Computational Ecology and Environmental Science

Developing novel computational tools and methods to predict and mitigate the rapid changes occurring in the earth's life support systems.



Understanding the earth's life support systems, and predicting and mitigating the rapid changes that are occurring in these systems because of human activities is one of the great global scientific challenges humanity is currently facing. The programme in ecological and environmental sciences aims to contribute to meeting this challenge by working with the scientific community to identify critical problems and develop novel computational methods and tools for addressing these problems. Problems range from the management and integration of the ever-expanding body of ecological and environmental data to developing novel data analysis and visualization methods to developing advanced predictive models of biotic and coupled biotic and physical systems at scales from local to global.

Team

We are a young and growing group with an extended family of collaborators in Europe and elsewhere.



Photo of Drew Purves
Drew
Purves

(Scientist)
Photo of Leeza Pachepsky
Elizaveta 'Leeza'
Pachepsky

(Postdoc)
Photo of Rich Williams
Rich
Williams

(Head of group)
Photo of Robin Freeman
Robin
Freeman

(Postdoc)

Projects

Some Projects in Development

Toolbox for Spatial Analysis of Invasive Species Spread.

Invasive species are causing significant economic and environmental damages worldwide. This project will develop a toolbox to calculate the rate of spatial spread of an invasive species though habitat, and to determine the factors that determine that rate. (Elizaveta Pachepsky)

Using 25 Years of Infra-red Satellite Data to Derive a New Global Fire Model.

The future of terrestrial carbon will be determined by the inputs and outputs of carbon to and from ecosystems, one of which – fire – is particularly poorly understood at global scales. This collaboration will process a large amount of infra-red satellite data to create a global, monthly time-scale map of carbon fluxes due to fire; and use these data to parameterize a new global fire model for use in Earth system models. (Drew Purves)

Ecological Data Management.

Working closely with academic partners to identify common themes and problems in the management of such data, we aim to create the tools that allow ecologists to collate, manage and disseminate their data in an efficient, powerful but easy to use way. (Robin Freeman)

Spatial Modelling and Optimization Tools for Conservation Science.

This project will develop a spatial modelling and optimization tools for optimal marine reserve design and other optimization problems in ecology and biology. (Elizaveta Pachepsky)

Data-constrained Simulation Modelling of Plant Growth.

Plant communities may act to amplify, or dampen, changes in the Earth's climate system caused by anthropogenic CO2 pollution; but current understanding of these potential effects is limited by a lack of quantitative knowledge and modelling capabilities for individual plant growth. This project will build a user-friendly interface for defining, parameterizing, and running simulations of non-linear biological models, and then use this tool to generate rigorously-parameterized plant growth models whose predictions can be trusted enough to integrate into larger analyses. (Drew Purves)

Analysing Animal Movement.

High resolution data from animal movement can now be collected allowing researchers to identify changes in the animals' behaviour. Here, we hope to create tools and techniques that allow researchers to apply these tools to arbitrary positional information. (Robin Freeman)

Building a Global Database of Forest Inventory Data.

Forests harbour around 60% of the world's biodiversity and around half of its terrestrial carbon, so there is an urgent need to predict how forests will respond to continuing anthropogenic perturbations including increased atmospheric CO2, logging and land-use change. To aid in the development and parameterization of models to predict these responses, this collaboration will collate millions of pre-existing field measurements of trees from national forest inventories, into a coherent, user-friendly database. (Drew Purves)