Environment – Page 5 – David Bradley

Alchemy Under the Spotlight

atlantic-bathymetry This week, The Alchemist is digging in the dirt to find out about the carbon cycle and climate change, taking his whisky (or is it whiskey) with or without water, and discovering how to juggle molecules, on the other hand. Also in biochemical news this week, the crystal structure of a plant hormone receptor is revealed while researchers in Israel focus on blocking the protein misfolding that occurs in Alzheimer’s disease.

And, under the December physical sciences Spotlight

It’s all in the marine mix – Mixing of surface waters in the Atlantic Ocean seems to have reverted in the winter of 2007/2008 to “normal” levels for the first time in almost a decade…

Well, wooden you know? – New materials that look and behave like plastics can be produced from a renewable raw material known as liquid wood. The bioplastics promise to displace petroleum as a feedstock for certain applications…

Running with knives – Stabbing is the most common form of murder in the UK and Ireland. However, while forensic scientists understand the basics of the process…

Dioxins in Pork

dioxin-pig Dioxins Before Swine – Irish pork is off the menu, according to the BBC.

The UK’s Food Standards Agency is monitoring pork products in the Irish Republic because of fears of contamination with dioxins. “Tests showed some pork products contained up to 200 times more dioxins than the recognised safety limit.” Interestingly, dioxin levels in soil have been declining in recent years, according to another BBC report from 2007. The alert over dioxins followed an alert after PCBs (polychlorinated biphenyls) were reported to have been found in Irish pork on 1st December after samples were taken 19th November.

There is some hint that machine lubricating oils contaminated with PCBs (stable polychlorinated biphenyls) may have degraded to release dioxins which somehow found their way into the pig feed. But, more likely is that non-feed grade oil is being used at some point in the cycle to dry biscuit meal (out of date biscuits and bakery goods from the food industry). Such non-feed oils obviously do not have the same quality controls as extra virgin olive oil and so could very easily have higher than food-safe levels of contaminants, including PCBs and dioxins. This suggestion hints once again, as did the ongoing melamine scandal, at how easy it seems to be for unscrupulous sectors of the food industry to use non-food materials in their products, allegedly.

So, what are dioxins and should we be worried about them?

Dioxin Dioxins are organic compounds formed when a huge range of materials, particularly chlorinated polymers (PVC plastics) burn and in some industrial processes. They are ubiquitous in the environment and became the focus of environmental activism because of their reputation for being among the most toxic compounds known. Colloquially “dioxin” is talked of as if it were a single compound rather than a class of compounds, but the most usual reference is to the chlorine-containing compound 2,3,6,7-tetrachlorodibenzodioxin. Dioxins should not be confused with the compound 1,2-dioxin and 1,4-dioxin, which are heterocyclic, organic, antiaromatic compounds.

2,3,6,7-Tetrachlorodibenzodioxin can have some nasty effects such as irritation to the eyes, allergic dermatitis, chloracne, porphyria; gastrointestinal disturbance, possible reproductive, teratogenic effects, liver, kidney damage, haemorrhage, and occupational carcinogenicity. But, does that long list of problems mean anyone eating any of the food products from Ireland – bacon, ham, sausages, white pudding and pizzas with ham toppings – were or are in any danger. “The UK’s Food Standards Agency said it did not believe at this stage that UK consumers faced any ‘significant risk’,” reports the BBC. Seems like fair comment, only serious chronic exposure to low levels of dioxins or acute high-level exposure are of real concern.

No member of the public has ever died from dioxin poisoning, despite the fact that for several decades industry has been inadvertently releasing these materials into the environment as impurities in hundreds of products and that countless burning materials release the same supposedly deadly compounds across the globe continuously. Occupational exposure has led to probably at most four deaths from industrial accidents involving the release of dioxins, according to John Emsley writing in The Consumer’s Good Chemical Guide.

Religious Faith in Technology

turner-cross The Elucian Islands in the virtual online world known as Second Life are to host a climate change conference. Speakers will present live from Imperial College London and Stanford University in California, and researchers and university students will attend from the UK and the United States.

However, another climate change conference with a difference also begins today in Sweden. That conference hopes to address the issues from a religious rather than a scientific angle with Christians, Muslims, Jews, Chinese Daoists and a native American representative, among others, taking part in the two-day event, which is the first of its kind, apparently.

It is timely then that a new scientific study of technology among religious people is to be published in the first 2009 issue of the International Journal of Innovation and Learning. The paper found that technological uptake seems to hint that the apparently more trusting character of many religious people makes them more accepting of new technologies. Though it pains me to say it, could religious faith by our saving grace?

If the devout are more inclined to trust new technology, then perhaps they will embrace more quickly novel suggestions for tackling the global issue of climate change. Or, does the research simply reveal that this trusting benevolence apparently associated with “being religious simply means that the devout are not quite so cynical of the hidden agendas of others, which make them more susceptible to the wiles of scammers, spammers, and charlatans.

The research paper discusses a relatively small-scale study into the link between strength of religious belief and how this relates to technology acceptance. The researchers wanted to find out whether people of faith are likely to be more trusting of commercial websites than other people.

With increasing commercial globalisation and international travel, the advent of the internet and online communities, the concept of social trust has become a key focus of research. Social trust has always played a crucial role in building societies and is based on the sum total of connections among people, their social networks and how trustworthiness is reciprocated. Civic participation is facilitated by social capital, as reflected in the social networks characterised by norms of reciprocity and trust, the researchers report.

In this context, they used a standard Technology Acceptance Model (TAM) to track online behaviour among a group of users and combined the data with results from an assessment of religious faith known as the Santa Clara Strength of Religious Faith instrument. The aim being to see how faith, trust, and technology mesh in the modern world.

The researchers questioned 161 current and former postgraduate university students and others with varying levels of internet experience and different religious convictions. They assessed religious strength based on dedication to prayer and how much a person’s faith plays a role in each individual’s daily life. Attitudes to ecommerce were assessed by testing their interaction with an experimental ecommerce website and asking whether users felt the website operated with their best interests in mind and whether it is run competently and sincerely.

An analysis of the results suggests that fundamentally religious faith increases benevolence, which in turn influences perceived ease of use, perceived usefulness and behavioural intention. The more religious were more trusting, it seems.

Although one might suggest that this would imply gullibility, the researchers extrapolate their findings to say that communities with strong religious faith may be among the leaders rather than the followers when it comes to technology acceptance, the early adopters in other words. Those people may be the ones paving the way for less trusting and accepting individuals.

The researchers say that it is surprising that religion, given its cultural prominence in some parts of the world, has been largely overlooked in studies of this kind. They hope that the present research will enthuse sociologists, economists, and business experts to investigate more closely how religious faith might affect internet use, with a view to improving the experience.

But, the big question of the day is who will you be listening to, the scientists virtualised in second life or those people of faith in Sweden?

Stuart J. Barnes (2009). Strength of religious faith, trusting beliefs and their role in technology acceptance International Journal of Innovation and Learning, 6 (1), 110-126

Blog Action Day on Poverty

We are, the media tells us, either on the verge or diving head first into a global recession the likes of which we have never seen. Countless financial headlines have screamed Credit Crunch, which sadly isn’t a wholegrain breakfast cereal for day-traders, for a year now. Banks are borrowing billions from taxpayers to allow them to lend even more money to each other.

There has almost been not a thought for the millions of people out of work and out of a home the ruins of whose lives the apparent collapse of capitalism is built. Anyone who thought Freddie Mac and Fanny Mae were porn star names, or the Lehmann Brothers were a support act for Marx (as in Groucho and gang) surely now knows better. Stocks and share prices yo-yo between lower highs and increasingly depressing lows.

But, away from the cold-sweating of traders, the pinging of stripy braces, and the red screens of death, on the market floors of the so-called developed world, the old-school third world, the allegedly developing world continues in its grinding abject poverty. However, providing the developed world does not collapse into utter chaos, Jenifer Piesse of the Department of Management, at King’s College London and the University of Stellenbosch, RSA working with Colin Thirtle of the Centre for Environmental Policy, at Imperial College London, and the University of Pretoria, RSA, suggest in a recent issue of the IJBT that at least one product of modern capitalism, genetically modified (GM), herbicide tolerant (HT) white maize, developed in the USA to save labour might help ease poverty in the developing world too.

They report how HT white maize is now being grown by smallholders in KwaZulu Natal, South Africa, and elsewhere and use panel data for Africa, Asia and Latin America to investigate the effects of factor endowments and biased technological change on productivity growth, labour incomes and poverty reduction. Can GM produce a Green Revolution (GR) in Africa and would it be poverty
reducing, as it has been in Asia, they ask.

Their preliminary findings demonstrate that a simple absence of population pressure on the land slows yield growth, which itself largely explains labour productivity growth in agriculture. Labour productivity growth is the key determinant of wages, growth in GDP per capita and poverty reduction.

“Africa seems to have fared poorly in poverty reduction because many countries have abundant poor quality land,” the researchers explain, “There has been yield growth, but it has not led to growth in labour productivity, as it did during the Asian green revolution.” This finding suggests that GM technology that raises labour productivity could be enormously beneficial, so long as employment is maintained.

Their analysis reports that yield growth in Asia was about 2.6% per year, but that Africa was not far behind at 2.0%. However, labour productivity in Asia grew at 1.5% per annum, whereas Africa managed only 0.4%. Yields in Asia grew at 1.1% faster than labour productivity and there was substantial progress in poverty alleviation. In contrast, in Africa, yields grew 1.6% faster than labour productivity, but the impact on poverty has been less.

They explain that yield growth is in fact a main cause of labour productivity growth in both continents, but in Africa the impact is far weaker. The most obvious cause is that both yields and labour productivity grow less where land to labour ratios are low, which is particularly true in the countries of sub-saharan Africa, the researchers say.

Jenifer Piesse, Colin Thirtle (2008). Genetically modified crops, factor endowments, biased technological change, wages and poverty reduction International Journal of Biotechnology, 10 (2/3) DOI: 10.1504/IJBT.2008.018354

This post was published as part of the Sciencebase contribution to Blog Action Day.

Melamine in the Global Food Supply

While melamine in the mainstream media seems to have quietened down in the last few days, there are still a few of us in the blogosphere attempting to unravel the tangle.

I first reported in my melamine in milk article (September 17) how the news broke that babies in China were somehow being poisoned by a contaminant in their formula milk powder. The contaminant was identified as melamine, an organic compound high in nitrogen and specifically amine groups that can dupe protein test equipment into thinking a product is rich in protein when it is not. Of course, the addition of non-nutritional organic compounds may fool the machine, but it does not fool the body of anyone eating the substance in their food and they will either be poisoned if the compound is itself toxic or suffer malnutrition. Infants, one might expect, would be particularly susceptible as they usually rely on a single food stuff – formula milk – for all their dietary requirements if they are not being breast-fed.

Nephrologist Robert Weiss, whom I interviewed for a follow-up item on the melamine toxicity article, told me that it is common to test for proteins using a simple test that detects amino groups (proteins are composed of amino acids). “Many non-protein compounds contain amino groups also (melamine is just one of those compounds). Some tests for proteins also are positive with ammonia, nitrates, and urea,” she says. “Unfortunately, none of these compounds can be used nutritionally speaking by animals or humans which ingest these compounds to build proteins. Therefore, these compounds have no nutritional value, are actually toxic and have no business being added to feed.”

One might suspect that manufacturers of these compounds as well as manufacturers of feed have learned how to outwit the somewhat simplistic tests for proteins that regulators use. “In learning how to outwit the tests in the interest of making a buck they have endangered the global food supply,” adds Weiss. It would be very interesting to know which companies are engaged in these practices or which are buying feed ingredients from companies engaged in such activities and so giving rise to the likes of the melamine contaminated food list. Perhaps this is simply an insidious symptom of the impending global recession, which is, as all recessions seem to be, founded on greed.

Weiss, who has ten years of experience in the pharmaceutical industry and is well aware of the chain of documentation required for drug production is “really amazed that we have less knowledge and control over ingredients and processing events in many of our foods.” Either way, the issue must be investigated and brought aggressively to the attention of legislators as well as consumers.

Revisiting Chernobyl

chernobyl-nuclear-power-plant Chernobyl. The very name strikes fear into the hearts of those who hate everything about the nuclear industry. It conjures up images of an archaic, burning industrial site spewing out lethal fumes, of farm animals dying of radiation poisoning in their thousands and contaminated meat, of ecosystems devastated, and of people with radiation sickness and for those spared the acutely fatal toxicity, the prospect of cancers to come and perhaps generations of mutations. But…

Korean researchers argue that while the 1986 accident at the Chernobyl nuclear power plant, Ukraine, was the worst catastrophe involving radiation to humans, but has led to an unfortunate and unwarranted degree of radio-anxiety. It is not radiation that is the health issue, but this anxiety.

Chong-Soon Kim of the Korea Institute of Radiological and Medical Sciences and colleagues say that despite warnings of pent up health problems from Greenpeace and the World Health Organisation (WHO), “there is no convincing evidence that the incidence of leukaemia or solid cancers have increased in the exposed populations.” They add that the apparent evidence of decreased fertility and increased hereditary effects has not been observed in the general population despite claims to the contrary.

According to the WHO, some 4000 people – emergency workers and residents – died or could die in the future because of Chernobyl. Greenpeace insists that this figure is almost 100,000 across the globe. Kim and colleagues point out first that although the incidence of thyroid cancer has increased in the Chernobyl area, it is actually regions less contaminated by radiation where the greatest incidence has been reported.

“In this case we have to be cautious on the point that the results came from extrapolation using insufficient individual doses, and so far deaths from cancer have not been reported as predicted,” say Kim and colleagues.

The radiation exposure level is the most important factor to estimate the cancer risk due to the Chernobyl accident. There are three types of exposed people. First, the exposure of recovery operation workers ranged up to about 500 millisieverts for a short period after the accident, with an average of about 100 mSv. In the case of evacuees, the average dose estimate of Ukrainian evacuees is 17 mSv (range 0.1-380 mSv), and the estimate for the Belarusian evacuees is 31 mSv, with a maximum of about 300 mSv. The average effective dose estimate of the general population in contaminated areas from 1986 to 2005 (some 5 million people) is 10-20 mSv.

The impact of Chernobyl on mental health and the future of nuclear as a viable renewable energy industry with public support, is perhaps the most serious problem. Among residents of the region and the emergency workers major psychological problems, such as depression, anxiety, and post-traumatic stress disorder are common. Anxiety levels are reported to be twice as high as in controls, the researchers say.

“Health effects, including cancer deaths, due to the Chernobyl accident have not reached the serious situation that was predicted,” the researchers say. There is, of course, some uncertainty in these figures although solid cancers usually form over a fifteen year period, rather than twenty years.

Young Woo Jin, Meeseon Jeong, Kieun Moon, Kwang Hee Yang, Byung Il Lee, Hun Baek, Sang Gu Lee, Chong Soon Kim (2008). Health effects 20 years after the Chernobyl accident International Journal of Low Radiation, 5 (3) DOI: 10.1504/IJLR.2008.020255

Zen and the Art of Global Maintenance

van-gogh-yin-yang A discussion a while back, over a few beers, with a Buddhist friend about life, the universe, and everything (what else?) got around to the subject of null physics and the notion that the universe may always have existed and may exist for eternity to come.

Sciencebase regulars will know that this concept is covered in a rather bizarre book I mentioned a few posts back entitled How to Discover Our Universe. While there is certainly room for improvement in current cosmological models this notion of an always having existed universe is not to everyone’s taste, at least in terms of conventional Western ideals. Indeed, it positively reeks of pseudoscience in the eyes of many of us raised on the conventional cyclic observation-explanation-prediction rote of modern science.

Anyway, it was almost inevitable that a paper with a Zen, or should I say, Daoist, inclination would land in my inbox. And so completing the circle in drops a paper from Philosopher of Science Anthony Alexander. Alexander is currently Director for Studies and Research at a structural engineering, conservation and urban design consultancy that is apparently pioneering sustainability in the built environment. But, that is not the focus of his paper.

He notes that the physics of the 18th century Western world was fundamental in establishing the basic concepts for the study of economics and our understanding of the fledgling Industrial Revolution. However, industry and physics have moved on, not least as a product of the almost exponentially increasing pace of technological change. It is perhaps this seeming progress and our need to consider a passage through time that many people cannot contemplate a universe without a beginning.

But, before you run to the hills or roll into a potential energy well, this post is not about to go all mystical and misty eyed. There are no implications or allusions to an Ayurvedic notion of quantum mechanics. There is no incense burner on my desk. And while there might be a yoga teacher working on my accounts as I type, there is certainly no ambient crystal and phoenix rising yoga therapy session planned for this evening in a padded room with all-natural oxygen bubbling through gently illuminated vials of dihydrogen monoxide.

Anyway, back to Alexander’s technique… He suggests that 18th century physics has been “comprehensively displaced by progress within Western science. The new larger field of understanding encompasses the complex, the chaotic, unpredictable and the fluid aspects of the real world. Unfortunately, the institutions of the modern world, the industries, the money movers, the pen pushers, remain firmly entrenched in a clockwork Newtonian world view whereas science is all about non-linearity of systems, probability of sub-atomics, and duality of energy and matter. This staid view considers the world to be stable and ordered, and human activity to be somehow fundamentally distinct from nature.

While environmentalism and green economics have the grand aims of redressing the balance it is actually globalisation, according to Alexander, that has raised our awareness of other cultures and their disparate world view that could provide us with the means to reconcile the Newtonian industries with modern physics and systems theory.

Alexander turns to one of his leanings – the martial arts – for inspiration as to how this might happen. The martial arts, kung fu, karate, judo, and their Daoist counterparts, invert the logic of Western combat. Training in the kicks, punches and locks of these various martial arts are aimed not at causing pain or injuring one’s training partner but in providing health benefits to both. A Western perspective might see an arm lock as a route to pain, whereas a practitioner of a particular martial art will see it as a way to build muscular stretch, for instance. Alexander sees parallels between this inverted logic of the martial arts not only with the concepts of modern physics but with the green economics.

The status quo of 20th century Western economics [which persists even now] can be challenged by green economics, [but] does not seek harm to anyone or anyone’s interests. It seeks to promote harmony and longevity – values that are at the heart of common sense, sustainable development and [martial arts] culture, which all parties stand to benefit from.

There really is no mysticism here, we are plunging head-first into global environmental crises. Physics underwent a paradigm shift to shake of Newton’s clockwork universe, perhaps, as Alexander suggests, we should work through his analogy and see green economics as the new paradigm for industry across the globe.

Alexander, A. (2008). Different paths, same mountain: Daoism, ecology and the new paradigm of science. International Journal of Green Economics, 2(2), 153. DOI: 10.1504/IJGE.2008.019997

Climate Change Debunked

climate-change So, how’s that for a blog post title? Catchier even than last Saturday’s New Harry Potter Trailer, right? So, is it just another spurious headline designed to grab attention or is there something in it? Well, you will no doubt have read about the recent APS debacle over the paper from Lord Monckton in which he stands up the anthropogenic climate change straw man and, pardon the pun, burns it down.

If you’re in the UK, or have figured out the BBC iPlayer hack to let you use that tool outside the UK, you may have seen the recent global-warming-coming-oil-crisis-we’re-all-doomed drama Burn Up. You probably also heard about a little fella called Al Gore and his inconvenient movie and the Channel 4 documentary that attempted to shred it, perhaps a little conveniently ignoring some key facts as it did so.

Meanwhile, power companies report massive profits and price rises for gas and electricity. They simultaneously pump up prices from well to wheel as the oil price bounces like a proverbial vulcanised rubber ball and everyone is looking to save gas.

I’ve published several items about alternative energy sources recently and still stand by the didact: waste not, want not. It’s important that we cut pollution and it’s important that we reduce the amount of energy we waste. We should be looking at what we are planning for the world, especially in light of madcap schemes like adding lime to the oceans, before it’s too late.

Joined Up Fuels

cars in snow The green morals of UK motorists are currently being held to ransom by the government. The government hopes to increase vehicle taxes based on how much pollution a car produces – it’s a green tax, a carbon tax, call it what you will. Some drivers will end up paying twice as much each year to keep their car on the roads. The bigger the car, the theory goes, the more fuel it will use and so the more polluting it will be in terms of pumping out carbon dioxide and so the more vehicle tax you, the driver, must pay.

Apparently, big cars (4x4s, MPVs, big estates, and anything over 2.1 litre engine capacity, built before 2001, will be exempt from the approximate doubling of vehicle road tax that is imminent. And, that’s certainly a good thing. Not least because our family seven-seater has a 2.3 litre engine and was made in 1998. It all seems to make sense, at first glance. Who could argue with that? Such a tax increase will force drivers of big gas guzzlers to swap their Kensington Tractors for something a little more environment friendly.

But, it is not as if CO₂ were the only pollutant, it’s not as if global warming were the only issue, and it’s not as if actually building new cars is a green process in itself. All those old-ish MPVs, are going to be sold on and new smaller cars bought, this drives the market, of course, and with an alleged recession pending, that might be a good thing in terms of economies. But, a quick back-of-the-envelope calculation will show that building a new car to replace that suddenly unwanted Kenny Tractor will expend far more energy and waste far more resources than continuing to drive it guzzling gas or not.

It seems to me that there is very little joined-up thinking when it comes to environmental issues. No one ever sits back and says, hold on a moment, when plans to potentially scrap millions of potentially serviceable vehicles for the sake of a tax saving comes up in discussion.

More to the point, the school-run of supersized vehicles, queuing up and belching out fumes while darling Jocasta and Joshua are delivered obesely to school without having to walk, is to some extend a tabloid a stereotype. Some people rely on the extra seats and space afforded them by the bigger car. One car transporting six or seven people, at an albeit lower mpg, is surely better than two cars wearing out the tarmac even at 10-20% lower total fuel consumption. Hummers and sports utes excepted, of course, but you don’t see many of those on British streets.

Karl Hillman and Björn Sandén of the Department of Energy and Environment, at Chalmers University of Technology, Sweden, seem to recognise this need for complete Life Cycle Assessments (LCA) including so-called Well-to-Wheel studies as they apply to the transport sector in general.

They have investigated how well decisions are being made as we strive to reduce pollution and to meet climate-change targets. They suggest that rarely are time and scale related factors given any attention, which I read to coincide with my points about swapping big vehicles for small at least in terms of energy wasted in the process and the splitting of transportation into ever smaller units.

Writing in the International Journal of Alternative Propulsion, the Chalmers team discusses how road transportation is currently responsible for 20-25% of world carbon dioxide emissions and is almost entirely (99%) dependent on fossil oil, despite the occasional hybrid siting.

To reduce oil dependence and greenhouse gas emissions, different policies are now being implemented to increase the share of motor fuels based on renewable energy. In the short term, the European Union directive on the promotion of the use of biofuels or other renewable fuels for transport forces the member states to set targets for the minimum use of renewable fuels.

Perhaps the UK government plans to use the extra tax it raises from gas guzzlers to develop renewables for transport so that it can meet EU and international targets more effectively. Somehow I doubt it, with deficits on every table, state-adopted banks heavily in the red, and a media-inspired recession just round the corner, I suspect every last penny will have been accounted for before you could say rapeseed methyl ester.

Hillman, K.M., Sanden, B.A. (2008). Time and scale in Life Cycle Assessment: the case of fuel choice in the transport sector. International Journal of Alternative Propulsion, 2(1), 1. DOI: 10.1504/IJAP.2008.019689

Mass v Gas and the Biomass Buzz

Biomass on the road to Rouen There are two main schools of thought when it comes to oil supply. There are those who believe that oil supplies are strictly limited and that we have passed the peak and will soon (40 to 60 years) run out of oil with which to power our vehicles. Then are those who believe supplies could last much longer than current predictions suggest. The latter school of thought believes there are either reserves that are simply too expensive to extract at today’s oil prices but they will be tapped ultimately or they believe that new sources will be found as the pressure rises. There is actually a third school of thought: those who believe oil is not a fossil fuel at all, but a continuously renewed material that will never run out, but that’s a different story.

During the 20th century and now into the 2000s, petroleum has predominated in fuelling transport hinging on the enormous growth of chemical engineering and chemical technology since the beginning of the industrial revolution. Currently, fuels from crude oil is used to fulfil 96 to 98% of the worldwide energy demand for cars, ships and planes.

Whichever school makes the grade in the end shouldn’t really matter, as Chemical engineers Maria Sudiro and Alberto Bertucco of the University of Padova, Italy, and many others have pointed out:

The currently known reserves of methane and of coal exceed those of crude oil by factors of about 1.5 and 25, respectively.

They reckon any analysis of fuel supply and the potential for using biomass as a so-called renewable source is not quite as clearcut as one might imagine. They explain that the problem of producing synthetic liquid fuels by alternative routes to conventional petrochemical means is mixed. The industrial processes of Gas To Liquid (GTL), Coal To Liquid (CTL), and Biomass To Liquid (BTL) use natural gas, coal, and biomass as feedstocks, respectively, all with varying efficiencies and resulting energy densities.

Now, writing in the International Journal of Alternative Propulsion (2008, 2, 13-25), the researchers have modelled each process on a weight basis per unit of feedstock (natural gas, coal and biomass/wood). For hypothetical plants running at a production rate of 100 tonnes per hour, they found that yields are about 70, almost 33 and just under 17%, respectively. Moreover, the carbon dioxide emitted per unit mass of liquid fuel is a relatively low at 0.9 kg for GTL, almost 5 kg for CTL, and over 6 kg for BTL processes. So, on the face of it, it would seem that gas-to-liquid fuel beats coal and biomass hands down in terms of efficiency and carbon footprint.

Of course, in some sense, the use of biomass can be thought of as carbon neutral as it is purportedly a renewable resource. However, such fudging of any analysis always seems to ignore the environmental impact of sourcing the biomass, whether that is the assimilation of waste for conversion, the planting of fuel crops, and the energy use and waste products of the conversion process. So, truly no solution is entirely clearcut when one takes into account the complete lifecycle of the fuel production process, well-to-wheel, as it were.

At first, site gas to liquid, may not seem necessarily to be the perfect option. This is especially so if one takes into account costs and political issues, such as access to a ready supply for any region hoping to exploit GTL. As such, the Padova team has evaluated production costs of synthetic fuel in a GTL process. They considered two different scenarios: the case of a production plant close to a natural gas supply. The second case is of a GTL plant remote from the country with the gas supply.

Their financial analysis reveals that the return on investment for a GTL plant with a local supply occurs in less than two and a half years, whereas it is almost seven years if the supply is in a country remote to the manufacturer. They conclude that given our reliance on oil, its derivatives, and putatively petroleum substitutes (and despite hybrid and hydrogen):

The economical and financial analysis has shown that it is extremely convenient to invest in a GTL plant located in countries where natural gas is available at a low price, thanks to the favourable return of investment.

It could be that as biomass becomes more accessible, possibly to the detriment of food and water supply, that the BTL approach to fuel becomes more viable. However, given the abundance of natural gas and the potential to release that from locked in sources, such as frozen methane hydrates, GTL could be the way forward for some regions of the world faced with dwindling oil supplies, especially given the lower carbon footprint compared with liquid fuels derived from coal or biomass.

Sudiro, M., Bertucco, A. (2008). Production of synthetic gasoline and diesel fuels by alternative processes using natural gas, coal and biomass: process simulation and economic analysis. International Journal of Alternative Propulsion, 2(1), 13-25. DOI: