Focus: Wood -Firing practice as a wood-firer or to help me answer those awkward questions that popped up at parties_ But what I found was a concern about carbon em issions which did not just focus on the use <strong>of</strong> wood and which overshadowed my concerns about forestry practices - how can I justify the release <strong>of</strong> over 60 tonnes <strong>of</strong> C02 each year from my kiln firings? Essentially, although the source <strong>of</strong> carbon doesn't matter in relation to the amount <strong>of</strong> carbon dioxide released, the source <strong>of</strong> the carbon is significant in regard to the impact on global warming. Over the last two hundred years, the release <strong>of</strong> carbon that was removed from the atmospheric carbon cycle and stored as coal and oil over millions <strong>of</strong> years has steadily increased the carbon dioxide levels in the atmosphere. This has some beneficial effects, such as improving plant growth, but its major negative impact is that, to date, it is has raised the average temperature <strong>of</strong> the atmosphere by 0.6°C, and is heading inevitably towards a rise <strong>of</strong> two or three degrees. After the Copenhagen conference, we all know that the reality <strong>of</strong> doing anything significant about it at a national and international scale is politically difficult. In order to restrict temperature rise to the target <strong>of</strong> 2°C, each <strong>of</strong> the nine billion people who will live on Earth by the year 2050 will have to restrict their release <strong>of</strong> carbon dioxide from fossil fuels to two tonnes per person. In his writings Steve Harrison has covered many <strong>of</strong> the things that he does, and that all <strong>of</strong> us should be doing, to lessen our 'carbon footprint'.2 We can do things as individuals, and I contend that wood-firing is one <strong>of</strong> the choices, considering wood is one <strong>of</strong> a few genuinely renewable fuels. To quote from my 1989 paper: " Compared to wood (and methane produced from a methane digester) al/ other fuels for kilns release carbon which has been removed from the atmospheriC carbon cycle by the process <strong>of</strong> burial and conversion into coal or oiU" <strong>The</strong> growth and then decay and decomposition <strong>of</strong> timber is a natural cycle in which carbon is removed from the atmosphere by the process <strong>of</strong> photosynthesis, and then released back into the atmosphere as carbon dioxide and methane by the decay or combustion <strong>of</strong> the timber at the end <strong>of</strong> the life cycle <strong>of</strong> the tree. Wood or biomass is regarded as a carbon neutral renewable resource. In Europe and the US, waste from industry and forestry is converted into wood pellets for use in automated boiler systems for central heating, and there have been suggestions that timber resources could be used for the production <strong>of</strong> base-load green electricity. Ray Cavill provides a comparison <strong>of</strong> different energy sources that can be used for the generation <strong>of</strong> electricity and the amount <strong>of</strong> greenhouse gases produced for each kilowatt hour <strong>of</strong> power produced 4 Energy Source (Coal-fired) Electricity LPG Native Forest Plantation Forest (<strong>of</strong>f cuts) kg CO2 per KWhr 1.00 0.34 0.03 -0.06 <strong>The</strong>se figures indicate that forest products used to generate electriCity would produce significantly less greenhouse gases than other sources <strong>of</strong> energy and that "the use <strong>of</strong> <strong>of</strong>f-cuts from sawm ill ing practices from plantation timber grown on ex-farmland results in a net carbon sequestration " 5 due to the sequestration <strong>of</strong> carbon in the product manufactured using the timber. In Australia, our forest resources regularly burn. <strong>The</strong> Black Saturday fires in 2009 would have released unimaginable quantities <strong>of</strong> carbon back into the atmosphere as carbon dioxide, but, even without that fire, over time that carbon would have been released into the atmosphere. And over time, those forests will once again remove that carbon. <strong>The</strong>re is a fossil carbon component in the cutting and transportation <strong>of</strong> wood for the use in kilns, and 26 THE JOURNAL OF AUSTRALIAN CERAMICS APRil <strong>2010</strong>
Focus: Wood-Firing Ian Jones, Basket, 2009 anagama-fired stoneware day h.31cm, w. 15cm photo: Stuart Hay Ia n Jones, Jar, 2009, Stoney Hole Creek granite clay h. 17cm, w.16cm photo: Stuart Hay THE IOURNAL OF AUSTRALIAN CERAMICS APRI L <strong>2010</strong> 27
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