Posted 2 years ago

What’s in a rose?

Since it is Valentine’s Day, I was searching for studies that had tried to estimate the impact of flower growing in terms of GHG emissions.  There are a few studies in this vein, but rather than dwell on the numbers too much there is an interesting angle on the often discussed ‘locally sourced goods’ debate, which is brought up in this study from Cranfield University.

It may seem intuitive that the closer something can be sourced to home (in this case ‘home’ being the place that some good will be used) would result in a lower GHG emissions than from sourced further away.  This is certainly true for some things - for example the effort required to extract inert materials such as aggregates is unlikely to vary by much, and therefore the transport element of its impact is likely to be of more importance.  It is also an argument that is made for many foodstuffs.

In the Cranfield paper, two cases of rose-growing are referenced which represent the two main exporters of roses (to the UK at least) - one in the Netherlands and one in Kenya.  Despite the fact that flowers from Kenya are flown in rather than shipped, the impact from growing them is much less per rose since they do not require unnatural heating and lighting and the average yield per hectare is greater.  The comparatively large energy demands on growing in the Netherlands more than outweigh and travel emissions incurred.

This does somewhat conflict with looking at the label on a bunch of roses with the automatic thought that Kenya seems to be an awfully long way away to be growing roses.

In my last post, I discussed how nations such as the UK have been ‘off-shoring’ a lot of emissions since national targets do not include imported goods.  However it is clear that in some cases, good carbon management is about doing the right thing in the right way at the right time.  In the case of roses, it is clear from this study at least that unless your European roses are grown in a renewable energy environment, it is better to grow them in Kenya which uses more natural resources.  Perhaps we should be promoting such efficiencies within a national or international GHG reduction strategy.

While buying locally is probably a decent indicator for lower impact for many things that we buy, as things become more complex it is not possible for any consumer to make an informed decision between two items.  How does one begin to examine the impact of a European car against a Japanese car? For the average consumer, this kind of knowledge is not well spread, and with Tesco’s worthy campaign of carbon labelling coming to an end it looks like it will be even more difficult in the future.

[Photo attribution: By Jebulon (Own work) [GFDL ( or CC-BY-SA-3.0-2.5-2.0-1.0 (], via Wikimedia Commons]

Posted 2 years ago

I noticed this interesting figure from The Guardian’s Datablog last week which puts an interesting question out there:  does a ‘national’ emissions target really drive the emission reduction policies that are needed?

(Note the data is based on other studies, including this paper)

It is often remarked that there has been good progress in the UK with respect to meeting emissions reductions targets set by Kyoto.  In the strictest sense, this cannot be disputed.  Emissions incurred within the borders of the UK have indeed reduced since 1990.  However the data above clearly demonstrates that there is a lot more to the story, and that emissions that the UK is responsible (in the non-legal context) for have actually increased in the same period.

This increase occurs despite a significant effort in decarbonising certain parts of the UK economy.  Therefore two reasons for the increase can be postulated: certain parts of the economy have been off-shored to countries with more carbon intensive production methods that the UK, or we are simply consuming more.  The reality is probably somewhere in the middle.

It is no secret that many of our goods are imported, and this is likely to be as important as any growth in consumption.  To a greater or lesser degree the same is true of most nations.  This means then when thinking about a low-carbon economy, due consideration ought to be thinking about how international partners contribute as well as emitters within national borders do.  

The way agreements such as the Kyoto Protocol are set up means that while some countries have defined emissions reduction targets, others - including those likely to be involved in large-scale export manufacturing, for example - do not.  As the data shows, this means that some emissions within a nation with a target could be off-shored, masking a real increase in emissions in a global context.

While a successor to the current Kyoto Protocol is still be be agreed, it will be interesting to see whether a more considered approach to this problem is forthcoming. 

Posted 2 years ago

This comic from xkcd is great and sums up one of the great challenges of communicating what sustainability is.  There is always the danger that phrases become buzz words and lose their meaning, which inevitably leads to fatigue and eventually loss of impact.

A danger of talking and communicating the ideas about ‘sustainability’ are invariably that it gets conflated with the issues of climate change and carbon emissions, which is somewhat of a paradox since is should be a topic that covers almost everything that we do.  In its purest form in a perfect future, the word should not even need to be uttered since it should be second nature to everyone.

Posted 2 years ago

Additional article on CCS

This article provides more of an overview of carbon capture systems and possible interactions on air quality, but is less focused on dispersion effects and more on general issues that need to be considered.

One of the key challenges for any new technology is overcoming the lack of guidance and in some cases regulation, and it is often not clear how existing guidance and requirements may apply to new technology.  Some of these issues are directly applicable to CCS.  For example it is not clear whether emission limit values apply before or after the CCS process for a thermal combustion process.  This is an important distinction since the CCS process removes considerable volume from the flue gas, but only a small amount of pollutants other the CO2, which means the overall concentration of other pollutants such as NOx could increase.  This may affect which abatement technology would be selected.

Posted 2 years ago

Air quality and CCS technical paper

I co-wrote this paper for the GHGT-10 conference in Amsterdam in 2010.  The paper covers the potential consequences that a carbon capture solution could have on air quality if installed at an existing site.  

The main influencing facture is the temperature of the flue gas release after the capture process, since this generally leaves the flue gas much cooler than when it entered the capture system, but will not necessarily have removed any of the pollutant content from that flue gas.

A further complicating factor is that it could be a significant engineering challenge to return the flue gases to the normal discharge stack in which case a new suitable stack is required.  Constructing a new stack can add considerable cost to a carbon capture project.

Posted 2 years ago


Hello world.

This is a place to share some thoughts on themes loosely based around environment, technology and the future.  I will try and keep those threads as far as possible. It will also be a place to digest thoughts from other places with comment.

Links to other things I have written will also be presented along with progress on other papers I am writing.

About me: environmental scientist working for a consultancy, with a strong interest in technology and how technology enables us.