The latest carbon auction under the Emissions Reduction Fund (ERF) happened last month. Some 47 million tonnes of carbon dioxide equivalent mitigation was purchased by the federal government at a cost of $516 million. To do this with solar power would cost $4 billion in subsidies.
The great thing about this, however, is not the carbon reduction. On its own that just doesn’t seem all that interesting. The great thing is the promise of reversing environmental degradation across the continent. Including by learning from and emulating indigenous land management practices – to which our ecosystems are adapted. This I stress is happening on farms and aboriginal lands all over the country. Sequestering carbon in soils and vegetation provides for a more productive and sustainable agriculture, flood and drought mitigation, real work for aboriginal communities farmers and environmental conservation. It is a multiple win scenario – and most of the changes in a transition to a 21st century agriculture is farmer driven.
Let’s take solar retailer Energy Matters at their word on carbon dioxide abatement cost. An entry level 1.5kW solar system provides some 78 tonnes of carbon dioxide abatement over 25 years at a subsidy of $6,200. This is an abatement cost of $80/tonne. Not dissimilar to a 2010 estimate from Climate Works. Typically if you look closely at these estimates – there are high ball estimates for coal, gas and nuclear technologies and low ball for wind and solar. But let’s not quibble. The price per tonne of carbon dioxide abatement in the ERF auction last month was $10.23.
Climate works calculated costs of 249 million tonnes of carbon dioxide equivalent (Mt CO2–e) abatement. This is based on a cumulative abatement target for a reduction of 5% of emissions by 2020. A convoluted concept indeed. Total emissions abatement of 150 Mt CO2–e are contracted for as a result of the three ERF auctions thus far. Options from Climate Works, on the other hand, range from continuing carbon intensity improvements – at a negative cost – to relatively low cost land use options and high cost energy changes – such as solar power. There are efficiencies at one end of the scale that merely continue the trend to increased carbon intensity – less consumption of energy for each unit of production – seen in recent decades. At the other end are currently expensive options for producing energy. It is likely that in future fossil fuel costs will rise as sources become more costly to exploit and as competition for supply intensifies. Alternative sources of energy – I think most prominently nuclear – will be cheaper in the near future.
Agricultural soils have lost organic content over a long time. The Intergovernmental Panel on Climate Change in 2013 estimated that cumulative carbon dioxide emissions from fossil fuels and cement production – from 1750 to 2011 – was about 365 billion metric tonnes as carbon (GtC), with another 180 GtC from deforestation and agriculture. Of this 545 GtC, about 240 GtC (44%) had accumulated in the atmosphere, 155 GtC (28%) had been taken up in the oceans with slight consequent acidification, and 150 GtC (28%) had accumulated in terrestrial ecosystems. The 180 billion tonnes of carbon lost from terrestrial systems is equal to 660 billion tonnes of carbon dioxide that may be removed from the atmosphere. Carbon can be returned to soils and vegetation using modern agricultural methods and with ecological restoration. Prominently in Australia as a return to firestick farming using the scientific application of indigenous knowledge. Growing tress from seed banks in soils is simple – the secret is in maintaining open woodland.
The French government launched its 4 parts in a 1000 initiative in Paris last year. They aim to restore soil organic content in grazing and cropping lands by 4 parts in a 1000 per year. The global land area is 13 billion hectares. Of that 5 billion hectares – 38% of the total – is agricultural. Cropping is some 28% of agricultural land, orchards 3% and grazing 69%. Cropping and orchards provides staples and nutrients – as well as culinary diversity. Grazing animals convert otherwise unusable resources on marginal lands into important sources of protein. Australia has about 400 million hectares of agricultural land. The potential for Australia is to remove 714 million tonnes – some forty percent of current emissions – of carbon dioxide from the atmosphere per year and return the carbon to soils. Globally much poorly managed land has turned to desert. Reversal of degradation of soils and ecosystems has the potential to not only reverse the 25% of greenhouse gas emissions from agriculture and forestry – but to return another 25% of current global emissions to soil and vegetation per year. The great promise of this is the multiple wins for global food security, economic growth and environmental conservation.