̽��ֱ�� of Cambridge - Christopher Howe

Photosynthesis ‘hack’ could lead to new ways of generating renewable energy

sc604 — Wed, 22 Mar 2023 15:57:53 +0000

Researchers have ‘hacked’ the earliest stages of photosynthesis, the natural machine that powers the vast majority of life on Earth, and discovered new ways to extract energy from the process, a finding that could lead to new ways of generating clean fuel and renewable energy.

Algae-powered computing: scientists create reliable and renewable biological photovoltaic cell

jg533 — Thu, 12 May 2022 08:43:43 +0000

̽��ֱ��system, comparable in size to an AA battery, contains a type of non-toxic algae called Synechocystis that naturally harvests energy from the sun through photosynthesis. ̽��ֱ��tiny electrical current this generates then interacts with an aluminium electrode and is used to power a microprocessor.

̽��ֱ��system is made of common, inexpensive and largely recyclable materials. This means it could easily be replicated hundreds of thousands of times to power large numbers of small devices as part of the Internet of Things. ̽��ֱ��researchers say it is likely to be most useful in off-grid situations or remote locations, where small amounts of power can be very beneficial.

“ ̽��ֱ��growing Internet of Things needs an increasing amount of power, and we think this will have to come from systems that can generate energy, rather than simply store it like batteries,” said Professor Christopher Howe in the ̽��ֱ�� of Cambridge’s Department of Biochemistry, joint senior author of the paper.

He added: “Our photosynthetic device doesn’t run down the way a battery does because it’s continually using light as the energy source.”

In the experiment, the device was used to power an Arm Cortex M0+, which is a microprocessor used widely in Internet of Things devices. It operated in a domestic environment and semi-outdoor conditions under natural light and associated temperature fluctuations, and after six months of continuous power production the results were submitted for publication.

̽��ֱ��study is published today in the journal Energy & Environmental Science.

“We were impressed by how consistently the system worked over a long period of time – we thought it might stop after a few weeks but it just kept going,” said Dr Paolo Bombelli in the ̽��ֱ�� of Cambridge’s Department of Biochemistry, first author of the paper.

̽��ֱ��algae does not need feeding, because it creates its own food as it photosynthesises. And despite the fact that photosynthesis requires light, the device can even continue producing power during periods of darkness. ̽��ֱ��researchers think this is because the algae processes some of its food when there’s no light, and this continues to generate an electrical current.

̽��ֱ��Internet of Things is a vast and growing network of electronic devices - each using only a small amount of power - that collect and share real-time data via the internet. Using low-cost computer chips and wireless networks, many billions of devices are part of this network - from smartwatches to temperature sensors in power stations. This figure is expected to grow to one trillion devices by 2035, requiring a vast number of portable energy sources.

̽��ֱ��researchers say that powering trillions of Internet of Things devices using lithium-ion batteries would be impractical: it would need three times more lithium than is produced across the world annually. And traditional photovoltaic devices are made using hazardous materials that have adverse environmental effects.

̽��ֱ��work was a collaboration between the ̽��ֱ�� of Cambridge and Arm, a company leading the design of microprocessors. Arm Research developed the ultra-efficient Arm Cortex M0+ testchip, built the board, and set up the data-collection cloud interface presented in the experiments.

̽��ֱ��research was funded by the National Biofilms Innovation Centre.

Reference

Bombelli, P et al: ‘Powering a Microprocessor by Photosynthesis.’ Energy & Environmental Science, May 2022. DOI: 10.1039/D2EE00233G

Researchers have used a widespread species of blue-green algae to power a microprocessor continuously for a year – and counting – using nothing but ambient light and water. Their system has potential as a reliable and renewable way to power small devices.

Our photosynthetic device doesn’t run down the way a battery does because it’s continually using light as the energy source.

Chris Howe

Paolo Bombelli

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Harnessing the power of algae: new, greener fuel cells move step closer to reality

cjb250 — Wed, 10 Jan 2018 11:18:27 +0000

As the global population increases, so too does energy demand. ̽��ֱ��threat of climate change means that there is an urgent need to find cleaner, renewable alternatives to fossil fuels that do not contribute extensive amounts of greenhouse gases with potentially devastating consequences on our ecosystem. Solar power is considered to be a particularly attractive source as on average the Earth receives around 10,000 times more energy from the sun in a given time than is required by human consumption.

In recent years, in addition to synthetic photovoltaic devices, biophotovoltaics (BPVs, also known as biological solar-cells) have emerged as an environmentally-friendly and low-cost approach to harvesting solar energy and converting it into electrical current. These solar cells utilise the photosynthetic properties of microorganisms such as algae to convert light into electric current that can be used to provide electricity.

During photosynthesis, algae produce electrons, some of which are exported outside the cell where they can provide electric current to power devices. To date, all the BPVs demonstrated have located charging (light harvesting and electron generation) and power delivery (transfer to the electrical circuit) in a single compartment; the electrons generate current as soon as they have been secreted.

In a new technique described in the journal Nature Energy, researchers from the departments of Biochemistry, Chemistry and Physics have collaborated to develop a two-chamber BPV system where the two core processes involved in the operation of a solar cell – generation of electrons and their conversion to power – are separated.

“Charging and power delivery often have conflicting requirements,” explains Kadi Liis Saar, of the Department of Chemistry. “For example, the charging unit needs to be exposed to sunlight to allow efficient charging, whereas the power delivery part does not require exposure to light but should be effective at converting the electrons to current with minimal losses.”

Building a two-chamber system allowed the researchers to design the two units independently and through this optimise the performance of the processes simultaneously.

“Separating out charging and power delivery meant we were able to enhance the performance of the power delivery unit through miniaturisation,” explains Professor Tuomas Knowles from the Department of Chemistry and the Cavendish Laboratory. “At miniature scales, fluids behave very differently, enabling us to design cells that are more efficient, with lower internal resistance and decreased electrical losses.”

̽��ֱ��team used algae that had been genetically modified to carry mutations that enable the cells to minimise the amount of electric charge dissipated non-productively during photosynthesis. Together with the new design, this enabled the researchers to build a biophotovoltaic cell with a power density of 0.5 W/m2, five times that of their previous design. While this is still only around a tenth of the power density provided by conventional solar fuel cells, these new BPVs have several attractive features, they say.

"While conventional silicon-based solar cells are more efficient than algae-powered cells in the fraction of the sun’s energy they turn to electrical energy, there are attractive possibilities with other types of materials," says Professor Christopher Howe from the Department of Biochemistry. “In particular, because algae grow and divide naturally, systems based on them may require less energy investment and can be produced in a decentralised fashion."

Separating the energy generation and storage components has other advantages, too, say the researchers. ̽��ֱ��charge can be stored, rather than having to be used immediately – meaning that the charge could be generated during daylight and then used at night-time.

While algae-powered fuel cells are unlikely to generate enough electricity to power a grid system, they may be particularly useful in areas such as rural Africa, where sunlight is in abundance but there is no existing electric grid system. In addition, whereas semiconductor-based synthetic photovoltaics are usually produced in dedicated facilities away from where they are used, the production of BPVs could be carried out directly by the local community, say the researchers.

“This a big step forward in the search for alternative, greener fuels,” says Dr Paolo Bombelli, from the Department of Biochemistry. “We believe these developments will bring algal-based systems closer to practical implementation.”

̽��ֱ��research was supported by the Leverhulme Trust, the Engineering and Physical Sciences Research Council and the European Research Council.

Reference
Saar, KL et al. Enhancing power density of biophotovoltaics by decoupling storage and power delivery. Nature Energy; 9 Jan 2018; DOI: 10.1038/s41560-017-0073-0

A new design of algae-powered fuel cells that is five times more efficient than existing plant and algal models, as well as being potentially more cost-effective to produce and practical to use, has been developed by researchers at the ̽��ֱ�� of Cambridge.

This a big step forward in the search for alternative, greener fuels

Paolo Bombelli

Kadi Liis Saar

Artist' impression

Researcher Profile: Dr Paolo Bombelli

Dr Paolo Bombelli is a post-doctoral researcher in the Department of Biochemistry, where his research looks to utilise the photosynthetic and metabolic activity of plants, algae and bacteria to create biophotovoltaic devices, a sustainable source of renewable current. He describes himself as “a plants, algae and bacteria electrician”.

“Photosynthesis generates a flow of electrons that keeps plants, algae and other photosynthetic organisms alive,” he explains. “These electrons flow though biological wires and, like the electrical current obtained from a battery and used to power a radio, they are the driving force for any cellular activity.”

Dr Bombelli’s fascination with this area of research began during his undergraduate studies at the ̽��ֱ�� of Milan.

“Plants, algae and photosynthetic bacteria are the oldest, most common and effective solar panels on our planet,” he says. “For billions of years they have been harnessing the energy of the sun and using it to provide oxygen, food and materials to support life. With my work I aim to provide new ways to embrace the potential of these fantastic photosynthetic organisms.”

His work is highly cross-disciplinary, with input from the Departments of Biochemistry, Plant Sciences, Chemistry and Physics, and the Institute for Manufacturing, as well as from researchers at Imperial College London, UCL, the ̽��ֱ�� of Brighton, the Institute for Advanced Architecture of Catalonia in Spain and the ̽��ֱ�� of Cape Town, South Africa.

“Universities are great places to work and so they attract many people,” he says. “People choose to come to Cambridge because they know the ideas they generate here will go on to change the world.”

In 2016, Dr Bombelli won a Public Engagement with Research Award by the ̽��ֱ�� of Cambridge for his work engaging audiences at more than 40 public events, including science festivals and design fairs, reaching thousands of people in seven countries. His outreach work included working with Professor Chris Howe to develop a prototype ‘green bus shelter’ where plants, classical solar panels and bio-electrochemical systems operate in synergy in a single structure.

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

Yes

Music in the tree of life

lw355 — Wed, 18 Mar 2015 10:00:29 +0000

When Joseph Haydn completed his Symphony No. 95, shortly before its first performance in 1791, he forgot to include the oboes.

Although Haydn corrected himself — his hastily scrawled ‘flauto’ and ‘fagot’ in the margin are crossed out and replaced by ‘oboe’ — this snapshot of musical history serves as an evocative reminder of human fallibility. It’s impossible to get things right all of the time, and no less so than for activities like the writing or copying of complex musical scores.

In fact, ‘mistakes’ are quite common in hand-copied texts and music. Before the introduction of printing in the late 15th century, the only means of spreading written culture was for monks and other scribes to replicate manuscripts. For music, the challenges of printing musical notation meant that hand-copying continued well into the 17th and 18th centuries.

Unwittingly, the careless scribes — and those who deliberately made changes, perhaps to fit their own style or contemporary fashions, or to ‘improve’ on an earlier literary or musical composition — were helping future historians.

Each time a piece was copied, the change was propagated, and occasionally joined by a fresh change. Scholars use these variations to build family trees of “which was copied from which” that chart the relationship between pieces, helping them to ask questions about the authors, and the history and even the movement of specific texts across continents.

Two such scholars are Professor Christopher Howe and Dr Heather Windram. Yet, they are neither historians nor musicologists. They are biochemists.

Howe is known for his work on photosynthesis and the molecular evolution of photosynthetic microorganisms. It turns out that there are important similarities between the evolution of a species and the evolution of anything copied successively — texts, music, languages and even Turkmen carpets.

“What’s exciting is how many different things follow this pattern of copying with incorporation and propagation of changes. It’s just a fundamental principle about how the world is,” said Howe.

“During the evolution of species, mutations that occur when DNA is copied are passed on and, as species diverge, you see their DNA sequences become increasingly different. Evolutionary biologists use what are called ‘phylogenetic’ computational methods to compare the variations and work out the family tree. We realised we could also do this for pieces of literature.”

His first work in the 1990s was on Chaucer’s Canterbury Tales. He and his collaborators found that the technique worked well and, with Windram, he proposed a new name for the process — ‘phylomemetics’ — “well, it’s easier to say than phylogenetic analysis of non-biological sequence data,” said Howe.

Very little work, however, has been carried out on music, until now. In what they believe is the first test case of this type of analysis, Howe, Windram and one of the UK’s leading early keyboard players, Professor Terence Charlston from the Royal College of Music, have used their sophisticated algorithms to trace the relationships among a set of 16 copies of the Prelude in G by Orlando Gibbons from the 17th and 18th centuries.

“Although music is a form of written tradition, we needed to pick up on the relationships between pieces in a different way,” explained Windram. “Music is a guide for performance so I was very conscious that some changes might be silent — like two tied quavers changing to a crotchet — but others might be sufficient to change the sound of the music.”

In each of the 38 to 39 bars of music (depending on the source), Windram looked for changes in, for example, the note pattern, pitch and rhythm. She knew it should be possible — she had previously worked on a text that had 16,000 points of variation — and, with Charlston’s expertise in 17th-century music, she was able painstakingly to unpick the ‘mutant manuscripts’ and turn the variations into a numerical code.

̽��ֱ��researchers are quick to explain that no computer analysis can replace the expertise of the musicologist, who considers a mass of other information in addition to the patterns of variation, such as the cutting edge research carried out by Cambridge’s Faculty of Music to capture the creative history of music in the Online Chopin Variorum Edition. Where Howe’s team sees a significant benefit of its evolutionary approach is the ability to exploit a large amount of complex information and then carry out multiple consecutive analyses very rapidly.

"Once the coding is complete, you can focus on specific aspects of the music,” explained Windram. “You can run the analysis again and again, perhaps considering only certain categories of changes, or only looking at a section of the music at a time. It’s another tool in the musicologist’s toolbox, and how you interpret what you are seeing is aided by their expertise.”

Just as scholars of texts are using family relationships to ask broader questions about literature, the same can be carried out with music, as Charlston explained: “We can use these techniques to look at the corrections made by a single composer. Take Bach for instance. He was an inveterate reviser of his own music as he performed or taught it, and we can use these techniques to look at the creative process from notation to how it lives through performance.”

What pleases the researchers is how the tool could also help performance choices in the future: “Current musicology tends to look for a single correct version but, for a piece like Gibbons’s Prelude in G, there may be as many versions as there are people playing it at the time. My ideal would be to suggest to players today that within certain confines they should be seeking to make their own variants,” said Charlston.

For Howe, the excitement of the approach also lies in what it might do for evolutionary biology. “We can use this technique to identify if a copyist is copying from more than one piece at the same time — called contamination. There is a parallel in biology called lateral gene transfer where unrelated organisms exchange DNA. We now want to see if a program that can handle contamination in text can tell us something about lateral gene transfer in living organisms.”

̽��ֱ��hope is that, like handwriting, musical notation will betray the hand of its composer or copyist. Analysis of variations in ‘mutant’ manuscripts — now carried out more quickly using the team’s phylomemetic tools — will help both to reconstruct musical history and to provide a tantalising glimpse of a creative process evolving.

Inset image, left to right: Christopher Howe, Heather Windram and Terence Charlston.

See and hear the visual and audible effects of the variants found between different sources of the same piece of Orlando Gibbon’s Prelude in G:

Example 1

Example 2

Both are from the same passage taken from the middle of Orlando Gibbon’s Prelude in G but from different sources; the variants occur in both hands. Example 1 is the original printed edition and Example 2 is a much later source held in the Fitzwilliam Museum in Cambridge. ̽��ֱ��right changes concern subtle alterations of pitch (often between f-sharp and f-natural) while the left hand bars differ mainly in rhythm and texture, but also with occasional changes in pitch. In addition to seeing the differences in music notation, you can hear each passage played on a 17th-century style harpsichord by Terence Charlston.

̽��ֱ��sound files were recorded by Terence Charlston in February 2015 using a single-manual harpsichord by David Evans built in 2014, after an anonymous French original dated 1676. ̽��ֱ��instrument is tuned in 1/4 –comma meantone at a pitch of a1 = 415Hz.

Modern scientific methods for mapping the evolution of species are being applied to centuries-old hand-copied music, providing new inspiration for how it is performed.

Evolutionary biologists use what are called ‘phylogenetic’ computational methods to compare the variations and work out the family tree. We realised we could also do this for pieces of literature

Christopher Howe

̽��ֱ��District

Music in the tree of life

Reconsidering the master of harpsichord

If you were a harpsichord player in the 17th century you almost certainly will have played Prelude in G by Orlando Gibbons (1583-1625). In fact, you are likely to have written out your own version, perhaps even ‘by ear’ while listening to your teacher.

Such was the esteem in which Orlando Gibbons was held that six of his compositions, including the Prelude in G, were included in the Parthenia – ‘the first musicke that ever was printed for the Virginalls [an instrument of the harpsichord family]’ in 1612-13, to commemorate the marriage of ‘the high and mighty Frederick, Elector Palatine of the Reine: and his betrothed Lady, Elizabeth the only daughter of my Lord the king [James I]’.

On one copy of the Prelude, now held in ̽��ֱ��Fitzwilliam Museum in Cambridge, an unknown hand has annotated it with the words ‘This is No 21 in the Parthenia & was a favorite Lesson(s) for upwards of a Hundred years’.

When Chris Howe, Heather Windram and Terence Charlston decided to try using their phylogenetic analytical techniques on music, Gibbons’s Prelude in G seemed a natural choice to make.

“Although it was available in print, few would have been able to afford to buy Parthenia, and yet almost all harpsichord players will have come across it,” explained Charlston. “It would have been copied and recopied by hand.”

̽��ֱ��researchers were able to track down 16 copies in existence in museums and libraries across the UK and in Japan and the USA. Although further copies may yet come to light, 16 copies were enough to carry out the analysis as a proof of principle.

“We wanted to see if the variants segregated into ‘families’ with similar relationships using phylomemetics,” explained Windram. “Even in this test case we found two main families that corresponded to manuscripts copied earlier and later in the 17th century.”

̽��ֱ��choice of Gibbons – who was a chorister in Cambridge’s King’s College between 1596 and 1598, where his brother was master of the choristers – has a personal resonance for Charlston. As Professor of Harpsichord at the Royal College of Music, and an internationally recognised performer, he knows Gibbons’s compositions well. “While he was famous in his own day, he isn’t widely known today,” he said. “This is a wonderful opportunity to reconsider him.”

̽��ֱ��text in this work is licensed under a Creative Commons Licence. If you use this content on your site please link back to this page. For image rights, please see the credits associated with each individual image.

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Low-impact hub generates electrical current from pure plant power

lw355 — Fri, 06 Mar 2015 09:00:52 +0000

A prototype “green bus shelter” that could eventually generate enough electricity to light itself, has been built by a collaboration of ̽��ֱ�� of Cambridge researchers and eco-companies.

̽��ֱ��ongoing living experiment, hosted by the Cambridge ̽��ֱ�� Botanic Garden and open to the visiting public, is incorporated in a distinct wooden hub, designed by architects MCMM to resemble a structure like a bus shelter. Eight vertical green wall units – created by green wall specialists, Scotscape – are housed along with four semi-transparent solar panels and two flexible solar panels provided by Polysolar.

̽��ֱ��hub has specially adapted vertical green walls that harvest electrons naturally produced as a by-product of photosynthesis and metabolic activity, and convert them into electrical current. It is the brainchild of Professor Christopher Howe and Dr Paolo Bombelli of the Department of Biochemistry. Their previous experiments resulted in a device able to power a radio using the current generated by moss.

̽��ֱ��thin-film solar panels turn light into electricity by using mainly the blue and green radiation of the solar spectrum. Plants grow behind the solar glass, ‘sharing the light’ by utilising the red spectrum radiation needed for photosynthesis, while avoiding the scorching effect of UV light. ̽��ֱ��plants generate electrical currents as a consequence of photosynthesis and metabolic activity during the day and night.

“Ideally you can have the solar panels generating during the day, and the biological system at night. To address the world’s energy needs, we need a portfolio of many different technologies, and it’s even better if these technologies can operate in synergy,” said Bombelli.

̽��ֱ��structure of the hub allows different combinations of the photovoltaic and biological systems to be tested. On the north east aspect of the hub, plants receive light directly, without being exposed to too much direct sun. On the south west orientation, a green wall panel is housed behind a semi-transparent solar panel so that the effect on the plants and their ability to generate current can be monitored. Next to that, in the same orientation, a single solar panel stands alone, and two further panels are also mounted on the roof.

“ ̽��ֱ��combination of horticulture with renewable energy production constitutes a powerful solution to food and resource shortages on an increasingly populated planet,” explained Joanna Slota-Newson from Polysolar. “We build our semi-transparent solar panels into greenhouses, producing electrical energy from the sun which can in turn be used to power irrigation pumps or artificial lighting, while offering a controlled environment to improve agricultural yields. In this collaboration with Cambridge ̽��ֱ��, the public can experience the plants’ healthy growth behind Polysolar panels.”

̽��ֱ��green wall panels in the hub are made from a synthetic material containing pockets, each holding a litre of soil and several plants. ̽��ֱ��pockets are fitted with a lining of carbon fibre on the back, which acts as an anode to receive electrons from the metabolism of plants and bacteria in the soil, and a carbon/catalyst plate on the front which acts as a cathode.

When a plant photosynthesises, energy from the sun is used to convert carbon dioxide into organic compounds that the plant needs to grow. Some of the compounds – such as carbohydrates, proteins and lipids – are leached into the soil where they are broken down by bacteria, which in turn release by-products, including electrons, as part of the process.

Electrons have a negative charge so, when they are generated, protons (with a positive charge) are also created. When the anode and cathode are connected to each other by a wire acting as an external circuit, the negative charges migrate between those two electrodes. Simultaneously, the positive charges migrate from the anodic region to the cathode through a wet system, in this case the soil. ̽��ֱ��cathode contains a catalyst that enables the electrons, protons and atmospheric oxygen to recombine to form water, thus completing the circuit and permitting an electrical current to be generated in the external circuit.

̽��ֱ��P2P hub therefore generates electrical current from the combination of biological and physical elements. Each element of the hub is monitored separately, and members of the public can track the findings in real time, at a dedicated website and on a computer embedded in the hub itself.

Margherita Cesca, Senior Architect and Director of MCMM Architettura, the hub’s designer, is pleased that it has garnered so much interest. “This prototype is intended to inspire the imagination, and encourage people to consider what could be achieved with these pioneering technologies. ̽��ֱ��challenging design incorporates and showcases green wall and solar panels as well as glass, creating an interesting element which sits beautifully within Cambridge ̽��ֱ�� Botanic Garden,” she said.

Bombelli added: “ ̽��ֱ��long-term aim of the P2P solar hub research is to develop a range of self-powered sustainable buildings for multi-purpose use all over the world, from bus stops to refugee shelters.”

̽��ֱ��P2P project was supported by a Partnership Development Award grant from the ̽��ֱ��’s EPSRC Impact Acceleration Account.

P2P is an outreach activity developed under the umbrella of the BPV (BioPhotoVoltaic) project working in collaboration with green technology companies including MCMM, Polysolar and Scotscape. ̽��ֱ��BPV project includes scientists from the Departments of Biochemistry, Plant Sciences, Physics and Chemistry at the ̽��ֱ�� of Cambridge, together with the ̽��ֱ�� of Edinburgh, Imperial College London and the ̽��ֱ�� of Cape Town.

Green wall technology and semi-transparent solar panels have been combined to generate electrical current from a renewable source of energy both day and night.

This prototype is intended to inspire the imagination, and encourage people to consider what could be achieved with these pioneering technologies

Margherita Cesca, MCMM Architettura

Yes

̽��ֱ��hidden power of moss

amb206 — Thu, 22 Sep 2011 05:03:47 +0000

Moss is regarded as a menace by gardeners who seek to eradicate it from their lawns. Now researchers all over the world are exploring how moss, algae and plants could be used as a source of renewable energy in the future.

A team of designers and scientists at Cambridge ̽��ֱ�� will be exhibiting a novel moss table at the London Design Festival later this week. ̽��ֱ��prototype table will showcase an emerging technology called biophotovoltaics (BPV) which uses the natural process of photosynthesis to generate electrical energy.

Featuring biological fuel cells made from moss, the table has been created as a vision of the future by Alex Driver and Carlos Peralta from Cambridge’s Institute for Manufacturing and Paolo Bombelli from the ̽��ֱ��’s Chemical Engineering and Biotechnology Department.

Still at early stages, BPV has the potential to power small devices such as digital clocks. Low cost BPV devices may become competitive alternatives to conventional renewable technologies such as bio-fuels in the next ten years.

̽��ֱ��appeal of BPV lies in its ability to harness a natural process that takes place all around us. Photosynthesis occurs when plants convert carbon dioxide from the atmosphere into organic compounds using energy from sunlight. Plants use these organic compounds – carbohydrates, proteins and lipids – to grow.

When the moss photosynthesises it releases some of these organic compounds into the soil which contains symbiotic bacteria. ̽��ֱ��bacteria break down the compounds, which they need to survive, liberating by-products that include electrons. ̽��ֱ��table designed by the Cambridge ̽��ֱ�� team captures these electrons to produce an electrical current.

̽��ֱ��table is based on research into biophotovoltaics funded by the Engineering and Physical Sciences Research Council (EPSRC). This pioneering work involves collaboration between the Departments of Chemical Engineering and Biotechnology, Biochemistry and Plant Sciences at Cambridge ̽��ֱ��, and the Chemistry Department at Bath ̽��ֱ��. ̽��ֱ��research is led jointly byDr Adrain Fisher, Professor Christopher Howe and Professor Alison Smith at Cambridge, and Dr Petra Cameron at Bath.

Carlos Peralta said: “ ̽��ֱ��moss table provides us with a vision of the future. It suggests a world in which self-sustaining organic-synthetic hybrid objects surround us, and supply us with our daily needs in a clean and environmentally friendly manner.”

Looking into the future, possible applications for BPV include solar panels, power stations and generators. Currently at concept stage, these are envisaged as sustainable solutions to pressing problems across the world – including the growing need for energy and fresh water from vulnerable communities.

“A modular system of biological solar panels would be mounted on to the roof of a building to supply it with a portion of its energy requirements,” explained Alex Driver “A biophotovoltaic power station would comprise giant algae-coated lily-pads floating on the surface of the ocean near the coastline, generating energy for local communities. A biophotovoltaic generator would feature algae solar collectors mounted on floating buoys and anchored just offshore to generate energy and harvest desalinated water, which is a waste product of one of the chemical reactions occurring in the device.”

̽��ֱ��Cambridge team emphasised that the technology was at very early stages. “It will be a long time before a product powered by this technology will be commercially available,” said Dr James Moutrie, Head of the Design Management Group at the Institute for Manufacturing. “ ̽��ֱ��table we are exhibiting this week demonstrates the ways in which designers can play a valuable role in early stage scientific research by identifying commercial potential and is one of the outcomes from our Design in Science research project.”

Scientists at Cambridge ̽��ֱ�� are exhibiting a prototype table that demonstrates how biological fuel cells can harness energy from plants.

̽��ֱ��moss table provides us with a vision of the future. It suggests a world in which self-sustaining organic-synthetic hybrid objects surround us, and supply us with our daily needs in a clean and environmentally friendly manner.

Carlos Peralta

Institute for Manufacturing, ̽��ֱ�� of Cambridge

Close-up of the moss pots incorporated into a novel table developed at Cambridge ̽��ֱ��.

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Yes

Plants not guilty of making greenhouse gases

bjb42 — Wed, 14 Jan 2009 00:00:00 +0000

̽��ֱ��latest study, by Dr Ellen Nisbet and colleagues, reported in the journal Proceedings of the Royal Society B, showed that although plants can take up methane dissolved in water through their roots and emit it through their leaves, they do not make methane themselves under normal conditions.

̽��ֱ��study contradicts a report published in 2006 claiming that plants make large quantities of methane themselves. Dr Nisbet's study shows that, although plants can emit methane, it is made by bacteria in the soil and recycled through plant tissues. Plants are therefore not guilty of making huge quantities of this potent greenhouse gas, and the finger is pointed at soil bacteria.

Commenting on the study, Dr Ellen Nisbet, formerly at Cambridge ̽��ֱ�� and now at the ̽��ֱ�� of South Australia, said 'It is a relief to know that plants are not guilty. Forests are immensely precious. Growing plants remove enormous amounts of carbon dioxide from the atmosphere each day through photosynthesis: carbon dioxide that would otherwise be causing global warming'.

Prof Christopher Howe, leader of the Cambridge ̽��ֱ�� team, said 'Although this identifies the source of a natural contribution to greenhouse gases, the imbalance that causes global warming comes from human activities that increase the atmospheric levels of greenhouse gases such as carbon dioxide'.

Prof Euan Nisbet (father of Dr Ellen Nisbet) who leads the group at Royal Holloway, ̽��ֱ�� of London, added that cutting anthropogenic emissions of methane is one of the easiest and cheapest ways to reduce greenhouse warming.

A study led by scientists at Cambridge ̽��ֱ�� and Royal Holloway, ̽��ֱ�� of London, has shown that plants are not guilty of creating tens of millions of tonnes of the potent greenhouse gas methane, despite earlier reports.

It is a relief to know that plants are not guilty.

Dr Ellen Nisbet

Robots_Rock from Flickr

Plants

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Yes