Energy to burn

by Amanda Holder (a PhD student at Aberystwyth University working on the multi-centre MAGLUE research programme)

As I have spent a lot of time over the past two years crawling around a field not far from the offices at Pwllpeiran I thought it would be a good idea to explain that there was a purpose to it!  It was all in an effort to record soil emissions of the greenhouse gas nitrous oxide emitted during the period of land preparation and planting of a new crop of Miscanthus (of course, why else!).

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Field work selfie!

In order to combat climate change there is a need to reduce emissions of greenhouse gasses such as carbon dioxide, nitrous oxide and methane into the atmosphere. Producing energy from plants to reduce the use of traditional fuels such as coal and gas can help to do this.  Miscanthus is a tall perennial grass, similar in appearance to bamboo, which can grow up to 3 metres in one growing season. Harvested annually its rapid growth makes it good for use as a biofuel (being burned to produce electricity).

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Miscanthus growing in plots at Pwllpeiran

As with all plants Miscanthus absorbs carbon dioxide from the air during growth.  However, it is important that the full greenhouse gas implications of converting land to Miscanthus are understood. This is where I come in.

The period of land use change can be considered a ‘hotspot’ for release of greenhouse gasses from the soil due to the  disturbance involved.  To investigate the extent of soil nitrous oxide fluxes during the establishment of Miscanthus a set of 12 trial plots were set up at Pwllpeiran.  Two types of Miscanthus (the commercially available variety and a new hybrid) were planted using different reduced tillage methods, with some plots retained as sheep grazed pasture for comparison. Minimum tillage (soil cultivated to a shallow plough depth before planting) and no tillage (Miscanthus planted in slots cut into the ground) methods were used for the commercial variety, and the new hybrid was planted with minimum tillage under a film mulch layer.

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The new Miscanthus hybrid being planted.

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The plots set up and testing soil emissions when grazed grassland is converted to Miscanthus.

To record the soil nitrous oxide emissions the hard work started before planting began, with samples taken before any intervention, and then continuing until the plants were 18 months old. To do this, in each plot, a circular plastic ‘collar’ was inserted into ground and then every two weeks a lid was clamped to the collar creating an air tight chamber.

A few spare chamber lids were stored in the field and proved to be popular with local wildlife …

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Field vole nest, latrine, and escape hole made underneath a spare chamber lid that was stored in the field.

…but don’t worry the vole kept his home for the year as the spares lids weren’t needed!

Samples of air were taken from inside the chamber through a rubber seal using a syringe. These were taken at 15 minute intervals over the period of one hour. The samples were then taken to the Centre for Ecology & Hydrology at Lancaster (a partner in the project) where they were analysed for levels of nitrous oxide.

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Gas chromatography machine used to analyse the samples of air taken from inside the sealed chambers.

In the end the study was more than worth burning up some of my own energy!  The results obtained can be used to help balance the pros and cons of land use change to Miscanthus.  It was found that soil nitrous oxide emissions from the cultivated plots were higher than the uncultivated sheep pasture, but levels were similar to those for when a grass ley is reseeded. There was no difference between the cultivation methods tested, or the type of Miscanthus. Work with mature crops of Miscanthus had already shown that their fluxes are very similar to pasture.  When specific emissions related to the cultivation ‘hotspot’ are put into the context of the 15-20 year crop life time the impact is small and overall greenhouse gas balances for using Miscanthus are less than for coal or natural gas.

If you’d like to know more you can read the full paper on the study here.


The things we do for sheep, and the distances we travel.

By Hannah Vallin


What do you say when your boss asks if you’d like to go to the one of the most remote islands of the British Isles in the Western Outer Hebrides of Scotland to catch sheep for work?! You madly jump at the chance and say yes of course!

But why do these sheep need catching I hear you ask?!

Back in April, Pwllpeiran received the great news that a large grant proposal submitted by the University of Edinburgh to collaborate on a long-term project on the Soay sheep of St Kilda had been successful. The Soay Sheep Project has been running since 1985, led by researchers at Edinburgh, who have been collecting a vast amount of data to study population dynamics and evolution genetics. It’s very exciting to be involved with the latest project, which is bringing together a range of disciplines to take a closer look at parasite infection and the impact of gut ecosystem dynamics on host fitness in the wild.  As for the Soay sheep, they are a unique little breed (emphasis on little). Soays are tiny compared to many of our domesticated breeds, mature ewes average at 24kg while mature males are slightly larger at 38kg. Don’t judge me for what I am about to say, but the lambs are extremely small and rather adorable!

IMG_6800                         A Soay lamb new to science this year, waiting for its ID tags.

Let me introduce the island to you. Hirta (or should I say Hiort in Gaelic) is the largest island in the St Kilda archipelago of Scotland. It really is ‘The island at the edge of the world’ as the book about its history so deftly describes it, I should know, as it took me three solid days of travelling to get there. After 675 miles, two trains, a mini bus ride, one ferry and a 55ft motor cruiser, I finally made it from Aberystwyth to Hirta, (commonly just called St Kilda nowadays). Hirta is a small island covering 8.5km² and the highest elevation at 430m. For those of you who have never heard of St Kilda, it has a truly amazing history with plenty of archaeological sites and ancient monuments scattered around the island to tell the story of St Kildans and their island life. Once inhabited for over 2000 years, the island was fully evacuated at the islanders’ request in 1930. The island is now owned by the National Trust for Scotland and since 1957 the island has been designated a National Nature Reserve by the Scottish Natural Heritage. Oddly enough, there is also the presence of the Ministry of Defence who have a small base for radar tracking of missile firing. St Kilda is one of the few World Heritage sites to have a mixed status for both its culture and natural attributes, which is just one of the things that makes it such a unique and interesting island.

IMG_6921                  A view of Hirta from the boat with Boreray Island on the right-hand side.

The island is unlike anything I have ever seen, whilst approaching it by boat it rises out of the sea quite suddenly with extraordinary steep cliffs, the highest sea cliffs in the United Kingdom in fact; very impressive. The surrounding waters and cliffs are teaming with tens of thousands of nesting sea birds including auks, gannets, Manx shearwater, puffins, storm petrels and many more. It is a twitchers’ paradise! During the trip we were incredibly lucky and also spotted a pod of Risso’s dolphins, along with two minke whale and large colonies of Atlantic grey seals with their bellowing calls echoing around the island cliffs.

IMG_6936            Two Atlantic Puffins (Fratercula arcticahaving a rest on the sea cliffs.

When I left Aberystwyth,  the Cambrian Mountains of Wales were looking like the Sahara Desert with fields of brown dead vegetation after the long dry summer spell we had been having. Arriving at St Kilda was a huge contrast, I was amazed at how green and lush the land was. A bright green landscape with clear turquoise waters in the bay; arriving on a beautiful sunny day it really was like a tropical island. I did fear the weather that day was lulling us into false security about what weather was to come during the rest of my time on the island. You probably won’t believe me when I say that actually we had good weather (most of the time), surprisingly warm and plenty of sunny days. We did have the occasional rainy spell but often the weather fronts would pass quickly over the island leaving behind interesting cloud formations forming over the hills. It was only on our very last day of catching and processing the sheep that it rained heavily, and yes, we were out in it all day long, I was very thankful that it was only on the last day!

IMG_2798                                         View overlooking village bay on St Kilda.

The reason for my trip to this far away island was for the summer catch, an attempt to catch as many sheep in village bay as possible. By catching, tagging and recording as many sheep as possible the research team have been following individuals from lambing, through the breeding season and recording any deaths on the island, building up a database of the sheep population over the last 33 years. At this point it’s worth reminding you that these Soay sheep are semi wild and are the most primitive form of our domestic sheep breeds today. There is no shepherd with a sheep dog or quad on the island to herd the sheep, oh no, meaning catching the sheep is a very interesting experience for sure!

A vast array of poles and netting are used to make traps and entrances strategically built around Village Bay, split between the West and East side of the village. This is not a quick or easy process. It took a good couple of days of building and carrying heavy netting up and down the hilly Village Bay (a good work out on the island!). Once the traps were in place it was a bit of a waiting game for the sheep to venture into village bay as they do during the day for grazing. When there were enough numbers, we made our move! What came next I can only describe as a fell running competition between man and sheep. Yes, the sheep outsmarted us on a few occasions, but with a good team (led by the experienced sheep catchers) and sheer determination we had many a successful catch whereby we pushed the sheep towards our net traps and enclosed them for processing. Now this may sound like an unconventional way to catch sheep, not sure it will be popular with sheep farmers on the hills of Wales but, it works for St Kilda. Don’t underestimate the method in the madness, it has been refined over many years and repeatedly successful for the island catch, and trust me, it works very well!

IMG_2896                                      Soay Ewe and lamb on ‘The Street’ in village bay.

Processing the sheep was a very much a team task and my favourite part, as we got up close and personal with this wild breed. Measurements such as limb length, horn type, coat colour, dental checks and weight were all recorded, along with a faecal and blood sample for every sheep. Think of it as their yearly health check.  In addition to this, there is a census count for the whole island population carried out every year.  This year’s total came to 1401, unfortunately this has declined on last year’s numbers, likely due to the harsh winter.  It is not unusual for these natural populations to fluctuate over time in response to environmental conditions, or the amount of vegetation available for grazing.  This highlights the importance of continued research to monitor population dynamics.

IMG_6783A catch of Soay sheep, mixture of ewes, rams and lambs displaying their variable appearance of coat colour and horn type.

Life on the island is very much a case of survival of the fittest, and that’s not just talking about the sheep.  A word of advice… this place is not somewhere to go if you suffer from vertigo, are prone to sea sickness, or if you have concerns being ashore a remote island with no communication with the outside world. For me however, it has been a trip of a lifetime, and it is somewhat difficult to portray the island when people ask me how was St Kilda?  I have learnt an awful lot, not only about the island but also about the long-term research of the sheep.  I had the opportunity to work with a great team of people and got to experience one of the most beautiful and surreal islands I have ever seen.  Believe me, I could carry on writing about my experience and happenings on the island for many more pages, but for now I shall leave you with a very appropriate quote by the naturalist James Fisher;

‘Whatever he studies, the future observer of St Kilda will be haunted the rest of his life by the place, and tantalised by the impossibility of describing it, to those who have not seen it.’


If you want more….. take a look at this short video of my trip to St Kilda!

A belated introduction

by Daniel Forster

So, after two and a half years, I finally get around to writing a blog post. I’ve been meaning to do this, but you could say I’ve been quite busy and it kept getting put to the back of my mind, honest!

Anyway, at least at this point I have things to talk about, so here we go. One rainy day way back in the early spring of 2016 I came to Pwllpeiran, bright eyed and bushy tailed, a short six months after finishing my undergraduate degree.  Back then I had a theoretical idea of what I was letting myself in for – it’s been an interesting ride so far, and I still have a few months to go so no time for a break just yet!

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Early days: what am I doing here again?

My PhD project is a collaboration between IBERS and CEH (Centre for Environment and Hydrology) Lancaster, where I’ve been going once or twice a year to meet my co-supervisor, use their lab equipment, and spend a bit of time around North-West England. The project itself has centred on the Brignant plots, which are set of long term grazing experiments situated here at Pwllpeiran and were set up back in 1994 to investigate the long-term effect of reduced management on upland fringe-pastures.  Over the years there has certainly been lots of change in the plant communities, particularly on the hay-cut treatments which are brimming with wildflowers throughout the summer, making them an excellent source of food for butterflies and other insects, and something of a temptation for the local livestock!  On the other hand, the grazing treatments are covered with a mixture of grasses that have gradually moved in to the plots as the soil fertility has reduced, reducing the numbers of sown species and creating a more diverse, if less productive sward.

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A year or so in: bright eyed idealism is replaced with consternation….

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The locals stop by to see what’s going on.

My focus for this project has been on ecosystem services, primarily the carbon stocks on the different treatments and how these vary in the soil, in the forage, and in the greenhouse gases produced as a by-product of raising livestock, basically sheep burps.

With a vague idea what I was doing, armed with little more than enthusiasm and sheer bloody-mindedness, I set out learning everything I could about grasslands, livestock, and soil ecology, and all manner of different but interrelated topics. I’ve been gradually bringing the project kicking and screaming from its nascent state as a jumbled set of objectives to something that with a bit of polishing and trimming (and a fair amount of writing) might actually pass muster!

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Daily watering last ‘summer’

Of course, it’s not all been work. There are plenty of other benefits to living and working in a place like mid-Wales, one of the most rural parts of mainland Britain.  The setting, in the Cambrian mountains surrounded by forests winding rivers, and err…sheep (did I mention the sheep?) is spectacular.  There have been plenty of opportunities for hiking and the odd spot of foraging, this year has been particularly good for wild fruit despite the uncharacteristically dry summer, which as I sit here writing this, appears to be more or less over.  Pwllpeiran has been an ideal place to live and study.

Back to the project, after 2.5 years of experiments, the last of the data is in after recruiting the help of two other PhD students.  With the promise of cake as incentive (cake passes for currency around here), we cleared the summer hay from the Brignant plots, and my task now moves from one of practical activity to one of honing my theoretical knowledge and writing skills as I dive into the writing up phase!

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Burying teabags for the organic decomposition experiment, now that’s a strong brew!

Spring out of winter

by Hannah Vallin

Remember the days of dry springs leading to warm sunny summers? Certainly feels like a long time ago. As they say in Game of Thrones “Winter is coming”, I am starting to wonder if it will ever leave now. The first snow fall of the year is always exciting, that powdery white stuff that makes everything look somewhat magical, and might allow for a day or two off work and school, great!  It was back in the middle of November when we saw the first sign of snowflakes at Pwllpeiran, and it has been a rather erratic and harsh winter since.  Over the last few months there have been several snow days, and recently thanks to the “Beast from the East”, Pwllpeiran really has been turned into the Welsh Alps.

snow1(The Alps of Wales)

With several inches of snow blocking the roads and temperatures falling well below freezing, the snowfall really has dictated how things happen for quite some time now.  For myself, commuting the 20 minute drive to work has been near impossible at times, it was off to work down at the Aberystwyth Uni Campus with a laptop instead.  But what about the livestock at Pwllpeiran I hear you ask, how will they get fed?! Well, our trusted man Gareth doesn’t let any amount of snow stop him from carrying out his duties.  With what I can only describe as an all-weather onesie and a sack of food on his back the sheep were well looked after throughout the freezing cold winter!  Our resident flock of Herdwicks did not seem phased by this winter wonderland, they actually seemed to quite enjoy playing around in the snow! These lovely little sheep are particularly hardy, a thick wiry coat that sheds water means they can cope well in extreme cold weather, perfect for up in these hills. Gareth has done an excellent job at keeping them safe with good shelter spots, and well-nourished with plenty of food.  But I reckon even the Herdwicks are longing for spring to be sprung , surly we are due some golden sunshine to defrost the hills soon.


snow2(Gareth working hard out in the snow)

What a difference a year makes, it’s hard to believe that this time last year at the beginning of March we had started to harvest our daffodil plots.  The everlasting cold spell has delayed the growing season this year, I don’t blame the daffodils for not wanting to raise their heads and flower in this weather.  However, the impact that the cold weather and snow is having on the daffodils might not be such a bad thing after all.   As you’ll recall, Pwllpeiran is testing a novel approach for sustainable daffodil-derived galanthamine production in the uplands, as an approved pharmaceutical product for Alzheimer’s treatment (more here).   The theory is, by growing the plants in a more stressful environment, aka the uplands, as a stress response they should produce more galanthamine.  As we are fast approaching the harvest season it will be interesting to see if the galanthamine concentrations have increased this year in response to the recent bad weather.

snow 3(There are daffodils under that snow….honest)

As my second winter at Pwllpeiran draws to an end I think I am going to invest in some skis, if I can’t drive to work I’ll have to take up cross country skiing! Or maybe I’ll get away with just playing on a snowboard. When you live out in the sticks of Cwmystwyth, you can’t assume that the roads will be gritted, let alone cleared once the snow drifts come in. If you’re lucky a very generous farmer will come along and literally dig you out with his tractor, which would be a lot more effective than me with a shovel!.  So, next time you are stuck driving behind a tractor wishing them to pull over, just remember all the help they give during every snow blizzard, flood or any other crazy weather event!

Let’s hope all this snow business is finally melting away until next winter, time for some sunshine, warmth and longer spring days please, we have harvesting to be getting on with!

(This blog was written for you, whilst snowed out of Pwllperian and stuck on campus yet again.)

snow4(A very helpful local farmer clearing the road)

My time going (Aber)Forward at Pwllpeiran

Guest blog by Damian Osmond

It was during that wonderful time of year we all know and love, exam season, that I received an email asking if I would be interested in working with the university as part of their AberForward scheme.  Looking for any excuse to distance myself from exams, I naturally filled out the applications and wondered idly about whether I’d see anything about the placement I opted for.  A couple of months later, I was stood in the wonderful hills in Cwmystyth, as we discussed agricultural practices with some visitors in what would later be dubbed as “my office”.

Damian hill view

The feeling you’re experiencing now is an odd mix of tranquillity and envy.

On paper, my roles were rather simple; help out with what I could, learn some new skills and assist with analysis and data collection.  However, it did not take long for my responsibilities to expand massively.

I mentioned data collection, this varied from taking grass cuttings, daffodil measurements, so many daffodils…  Sheep weighing and soil core taking, which was nice but rather odd to hear metal striking across all the hills, echoing like thunder.  I also had the opportunity to speak with some visiting school kids.  Now, I’d never worked with children before, but it was staggering just how many questions were asked.  To this day, I have no idea how local wildlife in the hills lead to me trying to answer about reverse scuba octopi, but what I can say is that no day in my eight weeks working were ever the same.

The hardest day there was when we represented IBERS at the Royal Welsh; it was still early into my placement, I had some idea of information to share about moss, peat and water retention but the heat made everything seem much harder than it was. Still, whilst a hard day, it was not the worst, in fact, during my time here I never did have a bad day.

Damian royal welsh

Never did find out if a rolling stone gathers moss.

Although, saying that, whilst not a bad day as such, the one I disliked most would have to be the day I overheard there would be sheep shearing and volunteered possibly too enthusiastically to assist with it.  The work was definitely interesting, and I can now say I’ve sheared a sheep!  (Even got to keep the wool.)  However, sheep are incredibly messy, and after the being avoided at lunch, due to the horrendous smell I had picked up, I had the joy of trying to remove many a sheep’s lunch and half a field from my clothes.

In all my time working with Pwllpeiran, my favourite role was just being part of the team; I was working alongside doctors, a professor, researchers and people with far more experience than myself but I was never treated less than anyone else or just as the temp to shift stuff or run tea.  I joked about my least favourite time there, but I think it has to be when I had to say my goodbyes and leave.  Still, the work done they do there is incredible, I could list all I learned but we’d be here until the next AberForward steps in, but I can’t thank everyone I worked with enough for the chance to be a part of the team, but thank you nonetheless!


Damian at the wrap up ceremony for Aber Uni’s summer 2017 AberForward scheme, talking about what he’d been up to.  He was one of only two placements out of 60 to present.

From the old to the new!

by Hannah Vallin

Last year, Pwllpeiran obtained a small amount of funding for additional engagement from the Joy Welch Educational Charitable Trust, (thanks to our PhD student Dan putting in the application) and the Royal Society of Biology.  The aim of the Trust is to provide funds for the promotion of educational outreach work.  So, what did we do with the funding?


The fun begins.

Here at Pwllpeiran we have many useful outbuildings surrounding our office centre. These include field labs for sorting and analysing samples collected from plots; drying and milling rooms; and garage space for the all-important machinery.  However, there was one particularly large space that was becoming a bit abandoned, collecting more and more boxes and cobwebs – it was time to make a change!  On a rare sunny day the whole team got to work clearing out the cluttered room, filling trailer after trailer with old rubbish, and re-allocating stored furniture.  It took the best part of two days to completely empty the space, and then the cleaning began….  Needless to say I made the others get rid of all the spiders!!  After endless hoovering and mopping, the place was clear and clean, and we could start to envision how to revamp the space.  As it is a breeze-block building we decided a lick of paint was needed to brighten up the space; even the floor got a shiny covering of paint.  With the addition of some benches, tables and notice pin boards we had a turned a dusty out-room into a great space to use for multiple events!


The big clear out – go team go!

As someone who loves to engage and inspire children into the world of science, I am keen to develop educational field sessions held at Pwllpeiran, making use of our newly revamped outbuilding, aka the ‘field classroom’.  Pwllpeiran represents a unique resource for education and research; for the University, local groups, and schools.  Thanks to the funding from the Joy Welch and the Royal Society of Biology  it was possible to purchase some ecology kits, magnifying lenses, vegetation quadrats, identification cards and tables for the new classroom.  With these facilities in place we were ready to invite small school groups to Pwllpeiran, offering the chance to attend organised ecology fieldwork sessions based on interactive learning experiences out in the field, supported by the field classroom back at the centre.


Finished, and ready for an event!

Since establishing our field classroom, we have had two visits from Plascrug Primary School, and held a session as part of Aberystwyth’s Summer University program.  Both events were very successful, thanks to my trusty sidekicks, PhD students Caroline, Ben and Dan who helped run the sessions!  Everyone, even the adults, had a lot of fun! Wellies and waterproofs on, everyone was ready for river kick sampling to identify fresh hv4water invertebrates and mini-beast hunts in the woods and grasslands.  Our best find was a bright pink and olive-green Elephant Hawk moth, caught by a young pupil who at the age of 10 already knew she wanted to be a zoologist (girl after my own heart!).  Plus, some budding botanists of the future very much enjoyed showing off their plant and tree identification skills.  Not to forget my favourite activity: learning all about super Sphagnum and its role in our pristine peat bogs.  It really has been a great experience to show off the area around Pwllpeiran, but the most rewarding part is seeing first-hand the excitement and inspiration on the pupils’ faces from the opportunity of learning in the great outdoors; priceless! As a certified STEM (science, technology, engineering and mathematics) Ambassador, along with the team at Pwllpeiran, I plan to continue developing our connections and educational outreach work with the local community.

For those of you who keep an eye on our Facebook page (find it here) I am sure you will have seen additional events over the summer, such as our Open Day and the Miscanthus safari tour, also took advantage of our new snazzy field classroom (yes, the name is sticking).  Look out for more events and visits in the future!!

Heat from the Hills


Rank Molinia tussocks – a fuel of the future?

by Mariecia Fraser

A few months ago, we were shocked and deeply saddened to lose our friend and colleague John Corton.  This blog is about an area of research he was tremendously passionate about.

Managing native grassland is a challenge right across Europe.  Its low nutritional value together with declining stock numbers has increasing led to under-grazing and agricultural abandonment.  But what other land use options are there for unimproved, semi-natural vegetation?  Especially if it’s been taken over by problem plants such as bracken, rushes and Molinia (purple moorgrass).  Dominance by these brings big biodiversity challenges, and large areas of hill land are now being mown by conservation bodies such as the RSPB, National Trust and Natural Resources Wales to try and maintain habitat value.


ProGrass was an EU project which was the first to consider bales of discarded vegetation being produced by this type of land management as a potential feedstock for bio-energy.  IBERS worked with partners in Germany and Estonia to test a pilot processing plant that turned this biomass into a liquid substrate for anaerobic digestion and a dry cake for burning.  The vegetation was cut and baled using standard (but robust!) farm machinery any time from mid-August on.  One of the advantages of using this type of vegetation as a bio-energy feedstock rather than a forage is that the decline in herbage quality over the autumn and winter doesn’t matter.  And waiting until the ground is frozen can mean areas that would normally be too wet to access can be cut, helping to knock back e.g. rushes.  Lots of great data was collected as the processing plant (known as Blue Konrad to his friends) toured across Europe.  Testing of the material produced confirmed that minerals that could damage boilers had been removed from the dry cake, making it suitable as a fuel.

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The processing plant (a.k.a. Blue Konrad) in Germany

Several follow-on projects have taken the ProGrass concept further.  Burning material at high temperatures without oxygen (a process known as pyrolysis) produces char, which everyone who’s ever had a go at cooking with charcoal knows has a high heat potential.  It’s also a great way of concentrating energy into something small and light.  Mobile char rigs could offer a great way to make the most of material located in inaccessible areas that would be too costly and difficult to transport out as bales.  The latest project has us working once again with several of the ProGrass partners plus new collaborators across Europe to broaden the range of ‘waste’ green material being considered even further.

If the technical challenges of scaling up can be met and the economics work out we could have a triple win: reduced reliance on fossil fuels without growing extra biomass crops; improved biodiversity; and an alternative income stream for land managers.  And there’s an awful lot of land we can use without damaging sensitive areas.  The ideal set up could be to establish areas that are cut annually on a rotational system; with stock grazing on the greener, more nutritious, growth the following year; then a fallow year or two to build up the biomass again.  At a landscape scale this would be a great way of creating mosaics of vegetation at different ages and heights – just the sort of thing our rare upland birds and other wildlife love.


The rest of the IBERS ProGrass team: John, Iain & Jim.