Carbon Copy

arts & sciences collaborate in the Antarctic

A dream to create a network of under-resourced community radio stations powered by renewable energy is well on its way to becoming reality, thanks - in part - to two intrepid South Africans who were willing to brave the Antarctic to test equipment in remote and inhospitable conditions.

Cape Town filmmaker Siphiwe Ngwenya and Johannesburg music producer Ntsikelelo Ntshingila took part in a collaboration between the arts and sciences to test a mobile renewable energy unit for the non-profit Interpolar Transnational Art Science Constellation (I-TASC). The unit allows researchers to work beyond the confines of their Antarctic bases by providing power on the move, and doubles as a bivouac providing shelter for a few days without external support. Dubbed Umthombo Womlilo (Well of Fire) renewable energy unit, it's an official project of the International Polar Year (IPY) 2007-2008. I-TASC is described as a "decentralised network of individuals and organisations working collaboratively" toward the "interdisciplinary development and tactical deployment of renewable energy, waste recycling systems, sustainable architecture and open-format, open source media".

This unit's predecessor was used to run an Antarctic radio station and relay weather information to an internet website, and was functioning perfectly after a year of testing, so the team built Umthombo Womlilo. Now the unit's sleigh runners will be exchanged for wheels and taken "on a tour of schools and universities, and to the national science festival, Scifest Africa, to be held in Grahamstown next month. It would also be used to power Alex FM, creating a platform to create public awareness around IPY and I-TASC, with the end goal being to establish an international network of solar and wind-powered community radio stations." [Source: Cape Argus, 15 March 2008 - subscription required]

The I-TASC website notes:

In addition to raising awareness of Antarctica and the human interaction, legacy and impact in the polar regions, it is hoped that through this research we may also be able to build a modular renewable energy unit which can be adapted to have useful applications in each of our local contexts, running a community radio station in a South African township, a media lab in rural Jamaica, a housing project in Chile or a foreshore communication installation in New Zealand.

The next objective for the Antarctic work of I-TASC is to expand the polar radio station Radio SANAE to provide "radiophonic bridges between dispersed Antarctic research bases" for collaboration, and provide a platform for artists:

It will encourage artists participating in Antarctic residency programmes, and others to create audio-based art (sound art, new music, radio drama and other audio based practices) for broadcast. Using internet-based systems, and posted CDs, we hope to enable an interface between artists and musicians based around the world and the residents of Antarctica.

burden of proof

It's curious that economists, planners, politicians and mad hatters are prepared to accept the outcomes of  imperfect forecasting models as justification for substantial investment of public money in roads and other infrastructure needed to keep cities ticking over, while some of the same people won't accept action on climate change on the grounds that climate models are flawed.

Time and again transport models have been wrong in predicting how many people will drive on a new road, park in a public garage or take the bus. We transport planners know the limitations of the data that goes into the models, and we know that past trends can't always be translated into future patterns. We also know that the models are crude tools that in many cases don't tell us anything about how best to achieve policy objectives. We know all this, yet we are happy to give the decision-makers our numbers as a basis for deciding where to put your money. And they take comfort in recieving our numbers. Weigh up the costs and benefits, and make the call.

Why is it, then, that we are told not to risk damaging the economy with strategies to reduce carbon emissions on the grounds that science hasn’t proven beyond a shadow of doubt that carbon is the primary cause of anthropogenic climate change, and that global warming will damage the economy and human support systems if we don't do something about it? As pointed out in this article in LiveScience, science is never expected to "prove" a theory before the theory is acted upon:

Science simply arrives at the best explanation of how the world works. Global warming can no more be “proven” than the theory of continental drift, the theory of evolution or the concept that germs carry diseases.

We have to rely on the accumulation of miscellaneous bits of evidence - some of it circumstantial, some of it of debatable integrity - and at some point, make a call. It seems that this year, that point has been reached. Most of the world has moved on from debating the science and is focusing on response strategies. Which is not to say that the science no longer matters, as some have suggested. We need to improve our understanding of climate change cause and effect as we continue to refine our responses. But global public opinion has shifted from "no way" to "how". That's one giant leap for mankind.

sticky CO2

Storing greenhouse gas underground is a bit like storing nuclear waste: to be effective as a mitigation strategy, it has to be kept there indefinitely. Whether it's for carbon dioxide or nuclear waste, there is no proven long-term storage mechanism, so it would seem that the logical approach is to avoid creating these byproducts in the first place.

But we are sitting with a carbon challenge that won't go away quickly. We've already got enough of the stuff floating around to keep the mother ship toasty, and the rate at which we produce more of it is going up, not down. Because of this, climate scientists say we are already committed to global warming well into the future, even if we start reducing carbon emissions now. So what to do?

Unless we mothball everything that uses fossil fuels, and drastically reduce livestock herds right now, we may need to take carbon out of the atmosphere to avoid global warming consequences. With the best will in the world, planting trees just won't cut it. It's unlikely that we could plant enough to make a difference (it's proving difficult just to stop the destruction of existing forests, so can we really reverse the trend?), and trees are only a temporary carbon storage medium anyway.

Researchers have come up with an alternative; a device that vacuums CO2 molecules from the air. The molecules stick to absorbent compounds in the device, and then can be stored. Thanks to global air circulation, the device doesn't need to be located near the emission source; it can go wherever the carbon is to be sequestered.

building in a bag

Take one sack impregnated with cement, add water, inflate, and wait 12 hours. Result: one instant building. No sugar added.

That's a news item from 2005, but it's an engineering innovation too cool to ignore. What's it got to do with carbon? Not much, but if we're going to be experiencing more extreme weather, it's the perfect solution to house people displaced by flooding or other weather-induced emergencies. Adaptation is one aspect of a comprehensive response to climate change.

biocement: building with bugs

A lot of energy goes into manufacturing cement, which is a key ingredient in concrete. Since concrete is widely used in just about every country, strategies to reduce its embodied energy could significantly reduce greenhouse gas emissions related to the construction of buildings, bridges and other large-scale infrastructure. World Watch estimates that production of cement accounts for 5% of human-caused carbon emissions.

One approach to reduce embodied energy in concrete is to replace some of the cement with fly ash, which is a byproduct of coal-fired electric power generation. It's cheap and abundant, and also reduces the amount of water needed to make concrete.

Or, if you prefer the high-tech route, recent research has opened up an alternative.

Last year Murdoch University researchers [link requires site registration] developed new biotechnology capable of producing sandstone within hours, which could potentially revolutionise aspects of the construction industry. Bacterial solutions 'cement' material together by building up calcium carbonate or calcite, and strengths exceeding conventional concrete can be tailored to suit the application. Dutch funders GeoDelft are interested in using it for the construction of dykes, but there are many other applications.

From July this year, the Australian government is funding another research project, called "Carbonate Binding: An Ecologically Sustainable Alternative to Cement", to be carried out at the University of New South Wales:

Carbonate binding is a frontier technology that promises a new generation of advanced materials for applications in construction. Precast concrete accounts for a large and increasing portion of total concrete usage. Precast materials made by carbonate binding would offer several advantages over conventional precast concrete. The energy savings of a low temperature process with negligible greenhouse gas emissions would contribute immensely to the goal of an environmentally sustainable Australia. The reduced hardening period would offer substantial increases in productivity to manufacturers.

Using crystal growth on calcite particles for binding is not exactly new: organisms in coral reefs and elsewhere have been using carbonate binding for millenia. It's the attempt to harness the process that provides an opportunity to reduce the energy required to maintain and expand our human-built environment. If this can be done without significantly changing construction methods, then it should be relatively easy to adopt this approach. It remains to be seen whether it can be used on a large scale.

More info:

• Easy reading: For a great summary of embodied energy in different building materials, have a look at this Australian guide aimed at helping homeowners make decisions that will reduce the energy impacts of house construction or renovation. It also explains, in straightforward language, how embodied energy is calculated and why it's important.
• Slightly technical: If you like pretty pictures and mild intellectual stimulation, here are some photographic examples of carbonates.
• Highly technical: A detailed analysis of the use of fly ash as a replacement for cement in concrete.
• Off the chart: You might need a PhD to follow this explanation of how the creatures living in coral reefs rebuild their homes after a disturbance, using carbonate binding.

nanoengineering concrete

Cement has been used in construction since the Roman Empire, and according to an MIT report we now manufacture 2.35 billion tons of cement per year. One of the concerns with its widespread use is the huge amounts of energy used in its manufacture.

MIT researchers have found that cement's strength lies in the way its nanostructure is packed, and think it may be possible to find - or nanoengineer - a different mineral to use in cement paste, one that has the same packing density but does not require the high temperatures during production, conceivably cutting world carbon dioxide emissions by up to 10 percent. That would accomplish one-fifth of the Kyoto Protocol goal of a 5.2 percent reduction in total carbon dioxide emissions.

how now, brown cow?

As reported on Discovery Channel:

Farm animals like sheep and cows produce large amounts of methane gas when they digest their food. The gas then escapes out either end of the animal and into the atmosphere. This process accounts for one fifth of all the world's methane emissions, and since methane is a potent greenhouse gas, making cows and sheep less flatulent is a big priority in the fight against global warming. That's why a team of scientists in Western Australia has developed a vaccine that kills the methane-producing bacteria that live in the sheep's digestive tract. After two injections, the test sheep produced eight per cent less methane than before, and the scientists expect this percentage to increase as they refine the vaccine and make it more effective.

Hmmm. Maybe we should just eat more grain and less meat.