What is the future of transport?

This beguiling conundrum has intrigued western civilisation for many centuries. Since the invention of the steam engine in the early 18th centuries, people have been striving to predict what technological revolutions will be realised in our transport systems. The year 2000 was a popular benchmark for vehicular soothsayers, with personal airships, commuter rockets and nuclear-fission cars all being hypothesised as alternatives to the land-based mainstream combustion engine. Continue reading

Looking into Westminster’s crystal ball

Renewable energy is officially mainstream. Once the realm of tree-hungers and hemp-wearing hippies, now the clean and green revolution is on everybody’s radar. Financial giants Bloomberg have reported that renewables investment has overtaken that poured into fossil fuels; the Pope has weighed in as an ardent supporter of renewable energy; and the Germans even have a word for it (Energiewende). Recent figures bear out this tidal wave of positivity: in the UK, renewable energy is now consistently generating 20% of the electricity market (on a recent sunny and windy Saturday this topped 43%) and last year, 80% of new capacity installed in the EU was renewable. Continue reading

Hunting for a purr-fect solution

The recent addition of a feline companion to our family has poised us a question; what do you do with a problem like cat litter?

Michael the cat. Photo credit: Charly Stamper

Unless you’re the lucky owner of a cat who does their business exclusively outside, then your cat will invariably regularly present you with a small brown problem. Speaking to various friends and family members who own cats, the consensus seemed to be that the only satisfactory disposal route was via the rubbish bin (where the contents will end up in landfill, or in a slightly better cases, be incinerated to generate electricity). When coupled with the additional detritus of the litter itself and any containment, such as nappy bags or newspaper, this represents a fair amount of material heading straight to the residual waste pile. I decided to see if there was an alternative.

Problem 1: The brown stuff

Let’s delve into the murky world of cat faeces…feline excrement can contain a parasite called toxoplasma gondii, which is manifest in humans as the infection ‘toxoplasmosis‘. This disease can cause serious harm to unborn children and people with weakened immune systems, and thus any disposal method should take this into account  (N.B Cats are the only animal known to excrete the eggs of the parasite, so the same does not apply to dogs or other pets).

Cerebral toxoplasmosis as viewed under the microscope. Photo credit: Wikipedia Commons (Jensflorian)

It’s for this reason that cat faeces should not be flushed down the toilet.

The conventional wisdom is that this also prevents cat poo being composted in the same way as regular food or garden waste. Hot composting (where temperates exceed 70ºC) is an option, but not one most of the population could routinely sustain.

Problem 2: Litter-bugs?

The second part of the equation is the litter itself.  “Mineral-based” cat litter is the most commonly available (and cheap) option. Most of these litters comprise highly-absorbant clays such as bentonite or montmorillonite, materials which are strip-mined from as far afield as Wyoming and Brazil. Furthermore, clay-based litter does not readily break down and will persist in landfill for many years. You don’t need to be a sustainability expert to work out the relative carbon footprint of that option.

In the past, the only alternative was to experiment with homemade options such as saw dust or pine shavings (I’m pretty sure any discerning cat would have immediately turned their back on anything that involved intensive effort on their owner’s part). Thankfully, there are now some off the shelf ‘eco’ alternatives.

Cat litter made from recycled paper pellets. Photo credit: Charly Stamper

The trial

All this research left me none the wiser as to what to do with the bulk of my smelly problem. To me, it seemed a shame to rule out the composting option given that by its very nature, cat faeces is already partially decomposed.

After much deliberation, I decided to do a composting trial. Whilst most online resources rule out this, there’s a hardy community of kitty-composters out there. The technique is similar to normal green waste composting, though to err on the side of caution it is recommended that the waste is left to compost for a minimum of one year and that the finish product is not applied to fruit or vegetable crops.

Bearing this in mind, I went for a recycled paper litter; wood pellets are another possibility. The paper litter is 100% recycled and will decompose easily in any setting.

Two months in, and this is what I have so far:

Cat litter compost (month 2). Photo credit: Charly Stamper

All seems to be going well. The waste at the base is homogenous, brown and powdery, with no trace of the original components. There’s a visible bustling community of woodlice, worms and other insects, and I’ve also been mixing in some grass cuttings and newspaper. The odour is minimal, although to be safe I have placed this compost bin at the far end of the garden.

Of course, the most important part of any trial is user participation. I’m happy to report that since spending all this time researching cat litter, Michael has mostly taken to using the garden instead of his litter tray. I wouldn’t expect anything else from a cat.

Original post: http://betweenarock.co.uk/saving-the-planet/hunting-for-a-purr-fect-solution

Wales: Bin there, done that – what next?

10 March saw the CIWM Resource Conference Cymru 2015 being held in Cardiff Bay, Wales. The purpose of the meeting was to share good practice and innovation about recycling and resource management in Wales. Here’s what I found out (with thanks to CIWM/Wastepack for providing the bursary that allowed me to attend!)…

CIWM John Quinn
CIWM President, John Quinn, explains the market forces behind moving towards a circular economy in the UK. Photo credit: Charly Stamper

Ask anybody what Wales is renowned for and you can bet that rugby, mining, choirs, Sir Tom Jones and daffodils will make the list. But Wales now has another string to its bow, emerging as a world leader in how we manage our waste.

Continued devolution has granted component members of the UK ever more independence on how to tackle thorny issues facing their regions, and the Welsh Assembly Government has fully embraced this opportunity to depart from central UK government policy on issues around waste and recycling. To date, its single most effective act has been to impose implement statutory recycling targets for municipal waste – this means every local authority is Wales is legally bound to ensure that at least 52% of its household waste is diverted from landfill. The current recycling rate of 54% is one of the highest recycling rates in the EU and way in excess of the rest of the UK. Furthermore, Wales is committed to increasing this to 70% by 2025 and ultimately achieving zero waste to landfill by 2050.

Wales has recognised that there are clear economic drivers for achieving high recycling rates and being able to reprocess these materials locally. Resource security contributes to economic resilience by not relying on other regions or countries for key resources. This market stability then allows for forward investment, job creation and improvements in social welfare. An independent study by the Ellen MacArthur Foundation estimated that moving to a completely circular economy in Wales could generate savings of £1 – 2 billion per year.

On show at the exhibit stands, an example of 3D printing using 100% recycled plastic (fila-cycle.co.uk). Photo credit: Charly Stamper

The consistent message from both policy makers and industry is that in order for Wales to continue improving, the focus must be on producing high quality recyclates from municipal waste. Some of the strategies discussed included:

  • Better communication and engagement with householders; tackling the issue of trust and being more transparent about the end destination of waste
  • Reducing the frequency and/or volume of residual (“black bin”) waste collections
  • Moving away from weight based targets and co-mingled collections

The conference also provided an opportunity to share ‘on the ground’ success stories and innovation, such as bringing designers into household recycling centres to improve layouts and a trial scheme which showed that the introduction of transparent bags led to an immediate 10% reduction in waste.

With a population of 3 million people, 22 local authorities and a diverse range of demographic and geographic situations, the challenges facing Wales mirror that facing the UK as a whole. Despite the challenges that lie ahead, I left feeling optimistic and hopeful that Wales is showing the way for the rest of us to follow.

Wales Millennium Centre
The venue for CIWM Resource Conference Cymru 2015 – Canolfan Mileniwm Cymru (Wales Millennium Centre). Photo credit: Charly Stamper

Original post: http://betweenarock.co.uk/sustainable-development-2/wales-bin-there-done-that-what-next

HGVs – Hence Gas Vehicles?

This post was inspired by my recent attendance at the ADBA UK Biomethane & Gas Vehicle conference.

You may not own or drive a car, but it is almost inevitable that part of your day-to-day your is delivered by heavy goods vehicle (HGV). That Amazon parcel, the food you bought in the supermarket, the pint of beer you drunk in the pub…it all came on a lorry. This transport sector comprises a mere 2% of UK road traffic, yet is responsible for 20% of greenhouse gas emissions (GHG).

The majority of HGVs run on diesel, rather than petrol, due to its ability to generate greater horsepower per volume unit.

HGV traffic on the M25. Credit: N Chadwick
Heavy traffic on the M25. Spot the lorries! Photo credit: N Chadwick

Continue reading

Plastic packaging – a horror film

Zero Waste Week is an opportunity to reduce landfill waste & save money. In its seventh year, the week runs 1st – 7th September 2014. The theme is “One More Thing” – what one more thing could YOU do? Find out more at http://www.zerowasteweek.co.uk/ or on Twitter using #zerowasteweek

Ever since I spent a summer working on a landfill site, I think twice before putting any items of rubbish in the bin.

Yanley Landfill
Yanley Landfill site, south Bristol, during the Balloon Fiesta in 2007. The site is now closed and is being restored to woodland. Photo credit: Charly Stamper

Continue reading

What makes a volcano go bang? The Grenadines, Lesser Antilles

The world’s most explosive and dangerous volcanoes are located at destructive plate boundaries. Here, dehydration of the subducting tectonic plate initiates partial melting of the overlying mantle wedge and produces magma (and hence, volcanoes). Lavas erupted from volcanoes at these locations chart a huge variety of evolved compositions, testifying to the influence of crystallisation at depth in modifying the chemistry of the primitive magmas originally produced by the melting.

Continue reading

PhD reflections

Between a Rock and a Hard Place began as an Earth Science PhD blog in February 2013, as a place to ramble on about PhD life and general science topics. Almost two years later, some of the contributors have finished, others have submitted, and the rest are nearing the end. Over the next few weeks, the BaR contributors will be sharing some reflections on their PhD experiences. Taken from an original post on the Bristol Doctoral College blog.

PhD highlight:

My PhD highlight was the city of Bristol.

Having completed my undergraduate at Bristol, I never intended to remain in the same city for my PhD. Then an opportunity came up that was too good to turn down.

By the time I finished my PhD, I’d been in the same department for 7.5 years (!), but I definitely don’t regret being flexible and being prepared to stay. Bristol has a thriving academic scene and throughout my research I was able to interact with a constant flux of interesting and cosmopolitan people. Outside of my studies I got involved with student sports, which helped to prolong my undergraduate experience (even if my nickname was inevitably something along the lines of ‘grandma’), and Bristol itself is an evolving and exciting city – in my time here I’ve seen so much change that there hasn’t been a chance to get bored.

I know that some people in academia say that you shouldn’t do your undergraduate and PhD at the same place, but I truly feel like the most important aspect is have a stimulating project and inspirational supervisors. For me, this just happened to be at Bristol.

Is there anything more 'Bristol'? Photo credit: Flickr user Vaidotas Mišeikis
Viva Bristol. Photo credit: Flickr user Vaidotas Mišeikis

Top tip:

One of the best things about doing a PhD is the flexibility of (generally) being able to work whenever and wherever you want; however, most people find that slogging away in the early hours of the morning isn’t always the most productive approach. Try and treat the PhD like you would a job. Having a routine means that you’ll keep going even when lacking motivation, and limiting work to regular office hours during the week means that it won’t become an all-consuming, isolating experience.

Flexible working. Sometimes the hardest decision is what to order for dinner. Photo credit: Richard Arculus

The year ahead – twenty fift-green?

The start of January always seems to herald a surfeit of navel-gazing blog posts. Therefore, I thought I would attempt to broaden my horizons and consider whether, with only five years to go to meet the 20-20-20 EU climate targets, will 2015 be the greenest year yet?

Continue reading


Twinning is a phenomenon in mineralogy whereby a single crystal of a mineral has two or more parts in which the crystal lattice is differently orientated.

The shared surface between two twins is called the composition or twin plane, and the orientation to either other is determined by symmetry through rotation or reflection; this relationship is described by a twin law.

Schematic showing the change in crystal structure across a twin plane. Credit: Imperial College London
Schematic showing the change in crystal structure across a twin plane. Atoms are shared by the two twins at regular intervals. Credit: Imperial College London

Continue reading

Kick ’em Jenny

Kick ’em Jenny is a submarine volcano located 8km to the north of the Caribbean island of Grenada. It lies close to the small, uninhabited volcanic islands of Ronde, Diamond, Ill Caille and Les Tantes, though no physical evidence of the volcano is evident from land.

Location of Kick ’em Jenny. Credit: USGS

At least twelve recorded eruptions have occurred since Kick ’em Jenny’s discovery in 1939 (the last in 2001), and it is currently the most active volcano in the Lesser Antilles arc. Underwater surveys conducted over the last 50 years have demonstrated that the summit lies at a depth of between 150 – 250m below sea level, with the height varying as the volcano goes through cycles of dome growth and collapse. Continue reading

Facing up to the big V

The nights are drawing in, the air is getting colder and here in Bristol it seems like viva season is in full swing. Enough time has elapsed since my own viva that I thought I would share my thoughts about what to expect on the big day. Whilst everybody’s experience is different, from talking to fellow alumni there do seem to be some common themes:

Your examiners are human. The main thing to remember is that the examiners really just want to have a stimulating and thought-provoking discussion, followed by a trip to the pub. It’s also true to say that never again will somebody be so interested in your thesis (in fact, the examiners will probably the only two people to read the thing cover to cover), so try to make the most of it.

It's a little known fact that PhD theses are primarily used as insulation. Photo credit: Moyan Brenn
It’s a little known fact that PhD theses are primarily used as insulation. Photo credit: Moyan Brenn

Continue reading