Showing posts with label fossil fuels. Show all posts
Showing posts with label fossil fuels. Show all posts

Monday 26 June 2017

The power of pond scum: are microalgae biofuels a realistic proposition?

I've previously discussed some very humble organisms but they don't get much humbler than microalgae, photosynthetic organisms that generate about half our planet's atmospheric oxygen. Imagine then what potential there might be for their exploitation in a world of genetic manipulation and small-scale engineering? The total number of algal species is unknown, but estimates suggest some hundreds of thousands. To this end, private companies and government projects around the world have spent the past few decades - and a not inconsiderable amount of funding - to generate a replacement for fossil fuels based on these tiny plants.

For anyone with even a microgram's worth of common sense, developing eco-friendly substitutes for oil, coal and gas is a consummation to be devoutly wished for, but behind the hype surrounding microalgae-derived fuel there is a wealth of opposing opinions and potential some shady goings-on. Whilst other projects such as creating ethanol from food crops are continuing, the great hope - and hype -that surrounded algae-based solutions appears to be grinding to a halt.

Various companies were forecasting that 2012 would be the year that the technology achieved commercial viability, but this now appears to be rather over-eager. Therefore it's worth exploring what happens when hope, high-value commerce and cutting-edge technology meet. There are some big names involved in the research too: ExxonMobil, Shell and BP each pumped tens to hundreds of millions of dollars into microalgae fuel projects, only to either make substantial funding cuts or shut them down altogether since 2011.
Microalgae-derived biofuel
Manufacturing giants such as General Electric and Boeing have been involved in research for new marine and aircraft fuels, whilst the US Navy undertook tests in 2012 whereby algae-derived fuel was included in a 50:50 blend with conventional fossil fuel for ships and naval aircraft. Even shipping companies have become interested, with one boffin-worthy idea being for large cruise ships to grow and process their own fuel on-board. Carriers including United Airlines, Qantas, KLM and Air New Zealand have invested in these kerosene-replacement technologies, with the first two of these airlines having trialled fuel blends including 40% algae derivative. So what has gone wrong?

The issue appears to be one of scale: after initial success with laboratory-sized testing, the expansion to commercial production has encountered a range of obstacles that will most likely delay widespread implementation for at least another quarter century.

The main problems are these:
  1. The algae growing tanks need to be on millions of acres of flat land and there are arguments there just isn't enough such land in convenient locations.
  2. The growing process requires lots of water, which means large transportation costs to get the water to the production sites. Although waste water is usable, some estimates suggest there is not enough of this - even in the USA - for optimal production.
  3. Nitrogen and phosphorus are required as fertiliser, further reducing commercial viability. Some estimates suggest half the USA's annual phosphorus amount would need to be requisitioned for use in this one sector!
  4. Contamination by protozoans and fungi can rapidly destroy a growing pond's entire culture.
In 2012 the US National Academy of Sciences appeared to have confirmed these unfortunate issues. Reporting on the Department of Energy goal to replace 5% of the nation's vehicle fossil fuel consumption with algae-derived biofuel, the Academy stated that this scale of production would make unfeasibly large impacts on water and nutrient usage, as well heavy commitments from other energy sources.

In a bid to maintain solvency, some independent research companies appear to have minimised such issues for as long as possible, finally diversifying when it appeared their funding was about to be curtailed or cut-off. As with nuclear fusion research, commercial production of microalgae fuels hold much promise, but those holding the purse strings aren't as patient as the researchers.

There may be a hint of a silver lining to all this, even if wide scale operations are postponed many decades. The microalgae genus Chlorella - subject of a Scottish biofuel study - is proving to be a practical source of dietary supplements, from vitamins and minerals to Omega-3. It only lacks vitamin B12, but is an astonishing 50-60% protein by weight. As well as human consumption, both livestock and aquaculture feed supplements can be derived from microalgae, although as usual there is a wealth of pseudoscientific nonsense in the marketing, such as the notion that it has an almost magical detox capability. Incidentally, Spirulina, the tablets and powder sold in health food outlets to make into green gloop smoothies, is not microalgae but a B12-rich cyanobacteria, colloquially - and confusingly - known as blue-green algae. Glad that's cleared that one up!

If anything, the research into microalgae-derived biofuels is a good example of how new technology and commercial enterprise uneasily co-exist; each needs the other, but gaining a workable compromise is perhaps just a tricky as the research itself. As for Government-funded projects towards a better future for all, I'll leave you to decide where the interests of our current leaders lie...

Monday 1 November 2010

Hot doughnuts and cold fusion: a never-ending story?

When there is much at stake we have a tendency towards self-delusion, ignoring unpleasant facts and concentrating instead on elements that will hasten our goal. If there is any such thing as a holy grail in contemporary science it surely has to be power generation via nuclear fusion, seemingly "just decades away" for rather more than that length of time. So are fusion researchers allowing dreams to obfuscate the facts?

The first fusion research was conducted in the 1950s by the Soviet Union, using doughnut-shaped magnetic field generators called tokamaks. Since then, various methods have been attempted with varying degrees of success, although none have achieved the ability to offer a greater output of energy than the amount input. A prominent contemporary non-tokamak project is the Lawrence Livermore Laboratory's National Ignition Facility in California. The project's integrated ignition experiments started this month after 13 years' development, using 192 lasers to create an energy pulse thirty times greater than ever achieved previously. At a cost of £1.2 billion, the NIF is seen by many as the best hope yet, but is now at least 25% over budget as well as behind schedule.

Meanwhile, tokamak research is continuing at various facilities, the best known being Iter (Latin for 'the way' but initially ITER - the International Thermonuclear Experimental Reactor - at least until 'thermonuclear' was deemed an unpopular word). Now being constructed in France, Iter is a collaborative effort between the EU, the US, Japan, Russia, China, South Korea and India. It is due for completion around 2019, but at a cost of £13 billion, it is also way over original estimates. The list of collaborators alone shows the importance of this immense project: after all, the dream of limitless energy for our descendents is worth the comparatively small effort in our time (although interestingly the Canadian Government was unable to remain in the project due to lack of funds). Britain itself contributes only about £20 million to the project each year, but in addition hosts the world's most powerful tokamak, namely the Joint European Torus (JET) in Oxfordshire.

Whilst fusion researchers publicise the advantages over current fission power stations, successful nuclear fusion at Iter would still produce thousands of tonnes of radioactive waste, albeit dangerous for only about a century as opposed to the millennia for the half life of fissile waste materials. In addition, critics claim the immense costs would be better spread across a range of fusion projects utilising different techniques, whilst environmental groups point out the money could build immense numbers of renewable 'green' power generators, from wind farms to solar collectors.

Indeed, it does seem that the member nations are putting all their eggs in one basket, considering the failures and hyperbole of the past few decades. In 1989, claims of cold fusion turned out to be premature when the results could not be replicated, whilst a 2002 claim for bubble fusion (sonofusion) also appeared to be precipitate. However, this hasn't led to scientists and engineers abandoning these techniques in favour of tokamaks or laser fusion. So is the immensity of the potential reward enough to keep researchers flogging a dead hypothesis? Then again, if the NIF and Iter fail to produce satisfactory results after a few years' operations, perhaps another generation of scientists and engineers will reconsider these somewhat discredited techniques.

One interesting development in recent years is the growing community of amateur physicists who are building homemade fusion reactors for as little as £30,000. As bizarre as it sounds, most of the materials are fairly easy to obtain, but unlike amateur astronomers for example, it is easy to wonder how these pint-size projects can compete with the billion-pound schemes mentioned above. The amateurs claim that their attempts may serve to initiate professional interest (and funding) in their non-tokamak methods. In view of the potential dangers of electrocution and x-ray radiation, their dedication is clearly admirable, if a little crazy. Then again, our species has rarely achieved a paradigm shift by playing it safe.

What is obvious to many is that we cannot afford to stop investing in large-scale fusion research: success would mean a relatively safe supply of non-fossil fuel energy for areas of the world where wind, wave and solar power cannot offer an on-demand supply. Nuclear fusion would not be at the mercy of the weather, nor occupy the immense amounts of space required for wind and solar farms, even if the former are offshore.

My own opinion is that fusion power will be an unfortunate necessity, at least until we can reduce energy consumption and the human population to sustainable levels - the latter being possibly rather less likely than building a break-even fusion reactor within a human lifetime. Research over the next decade will continue to consume enormous amounts of money, but only posterity will show if this is a great enough effort to stem the deleterious consequences that fossil fuels are having on the politics and economy of our species, in addition to the irreversible ecological effects rapidly coming over the horizon.

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Sunday 7 March 2010

How green is my alley? Reduce, reuse & recycle

British artist Richard Hamilton's 1957 definition of pop art included the terms 'transient', 'expendable', 'mass-produced', and 'Big Business'. We've come a long way since similar contemporary cultural attitudes led to throwaway clothing and disposable furniture, but there's still plenty that needs to be done before we achieve anything approaching sustainable development. The recent news articles showing that like the Pacific, the North Atlantic Ocean has its own enormous patch of floating plastic waste, clearly define a multinational problem: but what can the average Briton do to help the environment?

The three green 'R's of reduce, reuse and recycle involve a lot of statistics published by a variety of concerns, ranging from manufacturers to environmental groups. Going with the old saying that there are lies, damn lies and you-know-what, how can the public find a way through the minefield? As an example, estimates for the UK's annual waste total vary from 100 million to 400 million tonnes - although even the lower figure is more than enough! In recent years there have been several scandals involving potentially dangerous waste collected by local councils for recycling, only to be sent to developing countries where it is picked over by scavengers. Clearly, in some cases, out of sight is also out of mind.

Perhaps this shouldn't be too surprising considering how quickly we've had to adopt ecologically-motivated measures, but another concern is the enormous regional variation in recycling collection, waste processing and recovery. Lack of processing plants and a deficiency of recycling knowledge within councils supply yet another example of the postcode lottery. In response to this some local communities are taking matters into their own hands, such as the Somerset village of Chew Magna, where the inhabitants are attempting to gain zero waste status.

In addition to the lack of processing facilities another issue is sorting, although the use of high-tech approaches such as x-ray fluorescence and infra-red spectroscopy may increase efficiency, especially of plastics where recycling can create enormous savings in everything from oil to water. It isn't just the percentage that is recycled that counts, but how effective the processing and recovery methods are and whether as a nation we can reduce the amount of waste in the first place. Britain is an intensely consumerist nation and as if we need further proof, our household waste continues to grow by about 3% each year.

One of the most astonishing statistics (you see, they keep on cropping up), is the estimated 17.5 billion plastic bags given away in British shops every year. This amounts to over 130,000 tonnes of plastic, very few of which are composed of biodegradable material. An example of how quickly habits could change is shown by Ireland's introduction of a tax on plastic bags in 2002, which lead to an almost immediate reduction of over 90%. What's the difference to the UK? As far as I can tell, it boils down to the simple fact that unlike in Ireland, we have companies who make plastic bags: far be it from the Government to inhibit sales within our increasingly pitiful manufacturing base.

Despite the popularity of city allotments we are so divorced from food sources as to blindly follow use-by dates without actually checking the food itself. Recent evidence, including personal experiments by yours truly, show that in many cases the dates are wildly pessimistic (fingers crossed, I haven't been poisoned yet.) Again the figures vary widely, but estimates for food wastage in Britain range from 2.5 million to 8 million tonnes per year, which even for the lower figure equates to 18 million tonnes of carbon dioxide. Food safety scares have a lot to answer for, but surely effective food science education of adults as well as children is the obvious solution? After all, it would save us at least £10 billion per year on our shopping bills.

Of course it isn't just the consumer who is at fault: British industry must bear much of the blame. Every year we each spend up to one-sixth of our food budget on packaging, much of which uses standard sizes to cut manufacturing costs at the expense of material wastage. We could do worse than look at South Korea, where over the past decade legislation has reduced both the size and materials that can be used for packaging processed foods.

Another issue is planned obsolescence. Both the Trading Standards Institute and the Office of Fair Trading investigate consumer claims of items ceasing to work shortly after the initial warranty expires, but there are plenty of less obvious instances of products deliberately built to limits short of their potential working life, such as printer cartridges and rechargeable batteries. More insidious still is the use of advertising and clever marketing, combined with long-term release cycles, to promote a more rapid replacement of items than is really necessary. This 'obsolescence of desirability' is particularly obvious with mobile phones, which rapidly outstripped manufacturer's sales estimates in the early 1990s and are now updated on the basis of a fashionable new function or user interface rather than improvements to their core purpose. There can be no better illustration of the needlessly short life span of electronic goods than the seven metre tall WEEE Man sculpture at the Eden Project in Cornwall, which is composed of the consumer goods the average British citizen gets through in a lifetime - including no less than 35 mobile phones!

One irony is that the rapid development of storage formats over the past few decades has created a cycle of obsolescence from floppy disks to laser discs at a time we most need to counter expendability. Perhaps the current generation of 'virtual' devices such as Ipods and Ipads will help offset this, as long as their material and energy costs don't outweigh the savings in paper and packaging.

We cannot be in any doubt that things are changing for the better, but the big question is whether it is fast enough. The world's third largest retailer, Tesco, plans to be carbon neutral…in about forty years time. Many office buildings are already zero carbon and the Government plans for all new homes to be built to this standard from 2016. Meanwhile the Welsh firm Affresol has developed TPR, a wholly-recyclable substance stronger than concrete yet made mostly of waste and intended to provide load-bearing walls for buildings; fingers crossed for their pilot project!

Obviously just cutting back on domestic waste and power consumption will not do as much as reducing fossil fuel usage, but every little bit helps. A final shocking statistic: every Christmas this nation uses 8,000 tonnes of wrapping paper. Do we really need that amount? And as for carbon-trading - that's a whole other issue...