The Coalition has promised that if it takes government in September, it will get rid of the price on carbon emissions established by the Australian Labor Party. In its place, the party will implement a Direct Action Plan, its way of reducing emissions. This plan relies mainly on carbon sequestration and funding industrial improvements through taxpayer-funded initiatives.

While the Direct Action Plan outline has been removed from the Coalition website, Opposition Leader Tony Abbott and the shadow Minister for Climate Action, Environment and Heritage, Greg Hunt, continue to state the plan is their climate initiative.

What does the Direct Action Plan promise to do?

The plan says:

The single largest opportunity for CO 2 emissions reduction in Australia is through bio-sequestration in general, and in particular, the replenishment of our soil carbons. It is also the lowest cost CO 2 emissions reduction available in Australia on a large scale. Through the Emissions Reduction Fund a Coalition Government will commit to a “once in a century” replenishment of our national soils and farmlands. Through the Fund we will support up to 85 million tonnes per annum of CO 2 abatement through soil carbons by 2020 – and reserve the right to increase this, subject to progress and evaluation.

The favoured sequestration strategy is soil carbon storage. This methodology is still controversial, and a review by CSIRO demonstrates the large uncertainties involved in long term storage of carbon in soil.

Because of these difficulties, the Coalition may need to supplement soil sequestration at least in part, if not entirely, with more certain sequestration methodologies, namely tree plantation, if it is to have any impact on Australia’s net CO 2 emissions.

The plan does include forestry measures. And on February 5, 2013, Greg Hunt confirmed on ABC News Breakfast that tree plantation would make up part of the plan.

I analysed the sequestration component of the plan to test its viability. To ensure the plan was given the best chance for success within this analysis, the selected assumptions were purposely designed in its favour.

This largely involved assuming soil sequestration would work and that, if not, the best quality plantations could be established and that the necessary high quality land could be sourced.

The species I selected as sequesters were the Tasmanian Blue Gum (Eucalyptus globulus) and Shining Gum (E. nitens), with optimum wood density of 600kg per cubic metre and an annual yield of 30 to 35 cubic metres of wood per hectare.

Can it be done?

A relatively modest reduction of 5% below the Australian emissions of CO 2 in 1990 yielded a sequestration target of around 77 million m3 of wood per annum.

Sequestration within biomass accounts for around 50% of that biomass’ dry weight. For this reason, sequestration becomes a major project if expected to compensate for greenhouse gas emissions on the order of many millions of tonnes.

To achieve the pledged return of an annual 85 million tonnes of CO 2 , Australian wood production would need to be around four times what it currently is by 2020. The minimum land requirements for this additional wood production would be close to two times the size of Sydney by 2020.

As my analysis relied upon the most optimistic assumptions, real-world limits to tree plantation were ignored and optimal yield was used. The real scale of the Direct Action Plan would be much larger physically, in management and in cost, with real world conditions.

If tree plantation becomes the favoured option, this also presents the additional land and fire management requirements of such a large project.

Sequestration will play a role in mitigation of anthropogenic climate change. However, it would need to be of an immense size, spatially and financially, if it is considered a primary activity, rather than complementary.

In short, while sequestration is of value, to rely upon it at this magnitude is unlikely to be viable, especially by 2020.

Is it cost-effective?

Sequestration is of value, but the scale the Direct Action Plan calls for appears unlikely to be viable, especially by 2020, and is likely to become very expensive as the scale is adjusted over time to deal with increasing emissions reduction targets.

It is unfeasible to imagine that any sequestration initiative of the magnitude required can be achieved without significant additional expense.

Placing this hand-in-hand with funding improvements to industrial efficiency increases the cost to the taxpayer. In the case of the latter, this would be to the benefit of polluters. The Coalition has stated that this will be achieved without further taxes. The only other option is a retraction of standing public services.

The ultimate goal will necessarily be to achieve carbon neutrality. In this case, soil sequestration simply could not fulfil such obligations without major shifts away from a carbon driven economy - we will have to reduce emissions if we hope to sequester all we create.

The Direct Action Plan seems unlikely to be a viable counter pathway to the established price on carbon, because a carbon price has intrinsic market-based motivators to decouple carbon emissions from economic growth.

Ultimately, a quick analysis demonstrates the plan is very unlikely to provide the returns promised by the Coalition and is most likely to increase in cost beyond what has been promised by the Coalition. This is especially true if the Coalition eventually plans to scale up to meet future reduction targets or if it becomes necessary to scale up, simply due to returns failing to meet current targets.

The full report, A Review of the Viability of the Coalition’s Direct Action Plan, can be downloaded here.