Views around CAT on 1st December

We have had a spell of cold and frosty days here at CAT, with head gardener Roger recording -10C on the night of 29th November. These cold, still days lend a Nordic atmosphere to this unique environment – and we felt we just had to share it with you!

Tarren y Gesain
Tarren y Gesail
Tarren y Gesain
Tarren y Gesail



Frosty hillside
Frosty hillside


Frost crystals on a bench
Frost crystals on a bench
Woodland walk picnic area
Woodland walk picnic area
Quarry outcrop
Quarry outcrop
View of the old quarry from the Woodland Walk
View of the old quarry from the Woodland Walk
Mossy slate
Mossy slate
Icy stones
Icy stones
Icy waterfall
Icy waterfall
Icy grass 'fingers'
Icy grass ‘fingers’
Icy grass 'fingers' close up
Icy grass ‘fingers’ close up
Frosty moss
Frosty moss
Lichen and moss
Lichen and moss
Tarren y Gesain
Tarren y Gesail

What’s on at CAT this summer?

Every day during the school holidays…

Enjoy special activities every day during the school holidays (18th July to 29th August). Get the kids out exploring nature and let them get creative with eco-crafts and solar boat-building. Take a guided tour or explore our brand new Quarry Trail. Just relax in our organic gardens or stop for lunch in the CAT cafe. See you soon!

Fun for kids!





Get crafty with natural jewellery making









Put your inventing cap on and build a solar-powered boat









Get up close to some amazing beasties on a slug & bug hunt




And adults too!





Take a guided tour to learn more about renewable energy and greener buildings










Explore our brand new Quarry Trail for amazing views across the old quarry on which CAT is built









Release your inner bodger with green woodcraft demonstrations every Wednesday





*School holiday activites run from 18th July to 29th August, with kids’ activities and guided tours on every day

To find out what’s on when, take a look at our events calendar at


Sustainable Building Courses at CAT

One of the great things about the Centre for Alternative Technology is the sheer quantity of architectural and design features around the site.

View from the Wigloo
The funicular Cliff Railway
Eco cabins

Indeed, it’s a rare treat to see modern design juxtaposed with the rugged Welsh landscape.

All of our buildings, old and young, demostrate how ecological design pays attention to both form and function.

These buildings serve as practical exhibits which show ways that ecological architecture and design take care of both the environment and wellbeing.

We run a number of courses which are connected to design and architecture,  varying from short courses on timber frame construction to a Professional Diploma in Architecture.

For more information about our short courses:

and graduate level courses:

MSc Students visit ancient ruin of Castell y Bere with ideas to build a Utopian Community

Susannah Trevelyan, who is volunteering in CAT’s media and marketing department, joins MSc students on an Adaptation Planning exercise in Castell y Bere.

Adaptation planning

Today I was lucky enough to be allowed a sneak preview into the  MSc Sustainability and Adaptation’s field trip to Castell y Bere, an ancient ruin of a 12th century castle that clings to a rocky out crop in the beautiful hills above Cardigan Bay. We had been split into two groups and given a brief earlier in the morning at the WISE centre; it was our job to design a utopian climate resilient community, that within 10 years would, amongst other things support a community of 500 and be carbon neutral. Given the positions of leaders of this new community it was our job to organise food security, energy security, communication networks, clean water and sanitation, fuel, and a political and trading system. Everything a community needs would have to be worked out and presented in a proposal by the end of the week. This was a chance to share knowledge and to discuss what we would really use to  build the foundations of the future.

Future Leaders? MSc students gather to kickstart their adaptation and sustainability planning project at Castell y Bere.
The MSc students gather as leaders of a new utopian society.
The rain held off for us as we approached the ruins at Castell y Bere.
The MCs students are asked to arrive on site in silence, so as to enable a clarity and personal approach to the sustainability and adaptation exercise.
Sustainability and adaptation planning in action with the sun shining on the MSc fieldtrip at Castell y Bere.
Lecturer Louise Halestrap gives us a few directions in terms of what we need to consider when prioritising our group adaptation and sustainability exercise.

In order to make this practical possible it was important that we make some assumptions about the project and its context, the following of which were given to us…

  • We must support a population of 500 people
  • We can use any land we can see
  •  We must increase the sites resilience against climate change
  •  We must be fossil free within 10 years
  •  We must be waste free
  •  We must be carbon sequestering
  •  We must be ecosystem enhancing
  •  We must develop non-growth trading

We organised ourselves according to areas of expertise and interest, and I ended up in the Health and Wellbeing group. Having worked in the arts, particularly within mental health I was acutely aware of the important role health and wellbeing could play in our utopian society, and was excited to be able to engage with the crossovers it had with other aspects of living. Maybe we could develop a preventative medicinal approach to health, with a nutritious diet and a medicinal garden? Maybe we could develop community through the farming, along with celebrations and festivities in accordance with the seasons…

On top of the world ! MSc students survey the surrounding landscape on their field trip at Castell y Bere.
On top of the world ! MSc students survey the surrounding landscape on their field trip at Castell y Bere.

Under the strict supervision of our kind course leader we arrived on site in silence, allowing all of us to naturally conceive of a vision on site. After half an hour we erupted into chatter and started to tackle some of the most pressing issues in our future community. Where would we get clean water from? Where would we live and what would we eat? These were just a few of the most pressing issues we needed to agree on before lunch, never mind the education and health system.

MSc Students on a fieldtrip at Castell y Bere.
MSc Students, team naz, getting their heads together to discuss the main concerns of this budding utopian community.

It soon became apparent that setting up a new utopian community wasn’t as simple as it sounds, with a multitude of complex issues needing investigation before we could move confidently on. To make the most of our time we decided to list all the potential resources the site offered and, then continued shaping the broader issues at hand.

Recording the natural resources available to use was an important part of the day.
Natural resources in the ruins surrounding Castell y Bere include a small meandering river, and pasture land, which maybe is in risk of flooding considering climate change?


MSc Field trip to the ruins at Castell y Bere.
Ancient oaks cover the steep slopes leading up the ruins at Castell y Bere . Maybe this would be a useful resource for our new utopian community.

What should we do with the ruins themselves? To put in perspective the heritage of the site, the history tells a tale not unlike that of Game of Thrones; The site of dramatic wars with the English, where the Welsh king Llywelyn the Great held his authority over the Welsh. In 1221 Llywelyn took control of neighbouring Meirionnydd from his son, Gruffydd; Llywelyn had previously placed Gruffydd in power there, but the father and son had fallen out. The prince then began to build the castle of Castell y Bere with the intent of controlling the local population and securing his new south-west border, which included the mountain trade routes between Gwynedd, Powys Wenwynwyn and Deheubarth. Castell y Bere was the first of several stone castles built by Llywelyn and the initial castle consisted of several towers positioned around a courtyard, situated on a rocky hillock in the Dysynni Valley near Cadair Idris. 

Maybe we should just forget the past, as some of the group suggested, deconstruct the castle and reuse the stones for our new buildings? A fierce debate ensued, with a multitude of ideas for the castle ruins thrown into the air.

To be able to take all these complex and relevant issues into account in our plans certainly gave us food for thought, and it was there i left the group to develop plans of their own. The sun  had shone down on us  making this a very enjoyable day, jam packed with juice discussion. I’m sure that by the end of the week, the MSc students will have fallen out and made up a million times, be a bit battered around the edges,  but also be a bit more knowledgable about exactly what it takes to plan for the requirements of future generations.

Come to our open day on 16th November to find out more about the masters degrees in Sustainability and Adaptation, Renewable Energy, Planning and the Built Environment. 

 Susannah Trevelyan

Media and Marketing Volunteer CAT.




The Dyfi Valley

Here at CAT we’re part of the Dyfi Biosphere – an area recognised by UNESCO as being particularly environmentally conscious, whilst also encouraging sustainable economic development.

As we slowly move into spring, complete with April showers in May, it’s easy to see why this part of Wales has been recognised as being rather special. CAT is privileged to both play a part in, and be part of, the Dyfi Biosphere.

You can find out more about the Dyfi Biosphere here.

The Dyfi Valley - photo by Burhan Saeed


How to make the most of longer days in the woods

If you manage woodlands you’ll know that spring heralds the time to reduce your timber harvesting. Richard and the CAT woodland team look at what opportunities the break in late spring and summer offers sustainable woodlands.

After what seemed like a long cold winter of rain and snow, some of you might have been worried that we’d never see spring! But with the first buds of blossom and the wild garlic flowering it seems that spring is finally upon us – though the rain is still here!

So what now for your woodlands?

Harvesting in April to May should be avoided in most native woodlands, especially those with dense ground flora. Indeed, it is best to avoid it in any managed woodlands until the autumn. This means spring provides the perfect time to start thinking about what products your woodlands can provide.

One of the easiest is to bind together Birch brash to create traditional “besom” brooms. Other uses for brash include bundling it up to create faggots for firing clay ovens. Long bundles of brash can also be used to stablise riverbanks and muddy footpaths. Willow can also provide the perfect charcoal for artists.

Chairs and gates are other potential products. They can be relatively quickly produced from green wood. Green wood is easy to use because it still contains sap, which makes the material easier to shape. If you want to develop this area of your business, a workshop can prove invaluable. Many sustainable woodland businesses use foot operated lathes to turn furniture legs and tool handles.

“The gentle interaction between the woodland and the woodsman, between wood and craftsman, is something to be cherished. The natural environment is our life support system and through understanding it we can step closer to making our communities more sustainable.” – Adam Thorogood, woodland management officer at CAT (you can read more here)

The warmer months also provide a fantastic opportunity to monitor the biodiversity in your forests. Ideally, we’d recommend that you record the different flora and fauna throughout the year but this can prove tough after the leaves have fallen. Trees become harder to identify and the forest floor can be masked by rotting leaves and snow or mud.

Managing a native woodland offers a great opportunity to promote biodiversity. Without active management, levels of life-promoting sunlight become reduced. The woodland understorey can become overgrown with brambles and high levels of nutrient run-off from agriculture can encourage prolific growth of plants like nettles instead of more diverse flora.

So as the local wildlife becomes more prominent over the next few months, you can witness firsthand how your sustainable management has affected biodiversity.

Many woodland owners may not realise that with a more considered approach to management they could get a wealth of rewards. More active management can help them make a bigger contribution to the economy, to carbon storage, whilst at the same time protecting and enhancing the environment and our heritage.

“Community woodlands are delivering a huge range of public and community benefits, including recreation facilities, biodiversity conservation, rural development and jobs, renewable energy through wood fuel, locally produced woodland products, social inclusion, and outdoors education.” – Coed Lleol Website

By hanging up our felling axes and focusing on biodiversity and green wood products until the nights draw in again, we can create truly sustainable woodlands.

CAT have approximately 30 acres of woodland under management, including a mix of species and ages. Our woodland experts teach on a series of short courses throughout the year. Find out more here.











































Photo: Building the new green roof display

Thanks to a generous grant by People’s Postcode Trust, CAT has been able to build a new green roof for the visitor centre. This photo gallery shows the steps that CAT’s Buildings and Maintenance Officer, Carwyn Jones, has used in the building process…

1. The old food-store is one of the oldest buildings at CAT. But it was in dire need of a new roof, so Alex and Carwyn got rid of the old one first. They managed to re-use the membrane though.

2. A frame was built for the new roof. The original timber was reused where possible but as you can see, we needed a lot of new wood. The new timber was sourced from local forestry.

3. Here you can see how Carwyn re-used the old membrane. He also installed a new skylight to increase the light levels in the food-store.

4. This special membrane has pockets in it that collect water to allow for slower drainage. Bigger grades of stone were used on the edge of the roof to border the frame.

5. Almost finished! A layer of slate chippings went onto the roof (notice the extra batons that Carwyn put in place to stop the slate sliding down the roof). Soon the roof will be planted with sedums, which will need less soil and be easier to maintain than turf.

Watch this space for more photos of the new roof. Why not come and see it for yourself over Easter? CAT has a full schedule of Easter activities over the holidays!

Photo: Biomass training at CAT

CAT’s new HETAS accredited Biomass facility is used for our Installers Short Course as well as allowing our postgraduate students to learn about the possibilities of biofuel heating. Check here for more information about Biomass.

Postgraduate study at CAT includes REBE and AEES courses, both of which teach students about sustainable heating.

The new short courses at CAT also include Building Regulations for Biomass Installers. This course is intended for heating engineers wishing to attend the Biomass for Installers course but have not undertaken the HETAS H003 and H004 courses.

Photo: A biofueled bus from Brighton!

Engineers Without Borders UK (EWB-UK) are no strangers to CAT, with five groups visiting us this year to learn about sustainable technologies. This week a group traveled from Brighton on a Big Lemon coach that runs on biodiesel from recycled cooking oil!

EWB-UK is a national student-led charity aimed at removing barriers to development through engineering and have a summer placement programme, which is now taking applications.