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Abstract: Domestic water heating in Australia conventionally uses electric resistance heating storage or gas fuelled water heaters. The Australian electricity supply has some of the highest greenhouse gas emissions factors in the world. Consequently, water heating is responsible for approximately 24 percent of residential sector greenhouse gas emissions in Australia. To assist households to move towards an energy efficient, low carbon future, a suite of market intervention programs to support solar hot water uptake have been introduced at both state and federal levels. These programs aim to improve the capacity of industry to deliver solar solutions, reduce the emissions intensity and net cost of household water heating, and increase the market share of the solar water heating sector. Incentives include: [•] Point of sale rebates and certificate-based programs for energy efficiency and renewable energy; [•] Regulations for new houses that encourage solar water heating installations; [•] Community awareness programs; and [•] Training programs for installers to ensure that tradespeople have the competencies to size systems and the skills to install them correctly. In some jurisdictions the incentive programs were performance-based, but in others a fixed rebate amount was available for all systems having performance above a minimum threshold. These programs have lead to the widespread expansion of the industry, with an almost doubling of the proportion of households with solar water heaters between 1999 and 2011. Installations in new homes have seen an even more marked increase: For example, regulations for new homes in the state of Victoria require the installation of a solar water heater or rainwater tank. This program has seen the adoption of solar water heaters in new homes increase fro m around 5% in 2004 to over 70% in 2011. Across most of Australia there are proposed regulations limiting the emissions intensity of replacement water heaters which will effectively ban resistance electric water heaters in most situations. Recently both South Australia and Queensland commenced their program for existing houses. It is expected that in the future these programs will drive an even greater uptake, which will go some way to insulating Australian households from price increases that may result from carbon driven future increases in the cost of energy. This paper discusses the various approaches and outcomes of the different programs and provides analysis of the basis of program success or improvements. Learning relevant to market interventions worldwide include [•] Continuity in program operation is necessary to allow industry to grow in a sustainable way. [•] Basing the incentive on independently derived performance results provides industry with a means of differentiating better products and provides purchasers with appropriate guidance. [•] Rebate program design should consider the consumer''s purchasing priorities. For example, a point of sale discount awarded as part of the purchase transaction aligns with the urgency of the purchasing process and does not require additional cash to be available from the purchaser. [•] Design of the schemes can not only produce a greater market share, but can also encourage the manufacture of lower greenhouse gas emissions products. [•] Market interventions can have unintended consequences, so the programs need to be monitored and flexibility maintained to changes to avoid poor outcomes. [Copyright &y& Elsevier]

Abstract: Currently, Australia emits approximately 600 MT equivalent of CO2 annually, of which approximately 30% is directly linked to the electricity generation using both brown and black coals. To restrain the CO2 emissions, coal based power generators are looking to retrofit the existing power plants with commercially available technology for the post combustion capture (PCC) of CO2 as well as invest in the new power plants with high efficiency steam cycles. Since Australian coals are low in sulphur and the coal-fired power plants are well away from densely populated regions, the flue gas desulphurisation (FGD) and de- NOX regulations are currently not there for the coal based electricity generation in Australia. This is not an advantageous situation for straightforward retrofitting of the existing power plants with 30 wt% aqueous MEA based commercially available PCC technology that has very limited tolerance for SOX and NOX (less than 10 ppmv). In addition, Australia is a dry continent with very limited cooling water availability for the power plants. Hence, the Australian power generators are considering both the power and the post combustion CO2 capture plants to be air cooled. This paper, therefore, assesses the impact of introducing post combustion capture of CO2 on the existing and new Australian coal-fired power plants, both brown and black coal-fired, in terms of the cost of electricity generation, the cost of CO2 avoidance, the cooling water demand and the overall plant efficiency. The existing power plants are considered to be conventional subcritical and supercritical single reheat steam cycle based whereas the new power plant designs have allowed for ultracritical steam conditions (35 MPa, 922 K) with double reheat. The CO2 capture plants are considered to be either in service full time or in service on demand with 90% capture efficiency and the product CO2 ready for sequestration at 10 MPa and 313 K. The process and cost models for integrated power and capture plants have been obtained using ASPEN Rate-Sep, Steam-Pro, Steam-Master and PEACE software packages for process modelling and cost estimation. The results clearly show that an air cooled integrated power and capture plant has lower overall plant efficiency and slightly higher cost of electricity generation in comparison with a water cooled equivalent plant. An ultracritical single reheat power plant when integrated with capture plant that is in service full time has potential for lowest cost of electricity generation with minimum cost for CO2 avoidance. These results further show that replacing an existing turbine with a new LP turbine optimised for continuous steam extraction for CO2 plant duty minimises the adverse impact of PCC integration but the power generator looses the flexibility for electricity generation. The results also provide important insights into the major contributions to the increased cost of power generation. For both the existing and the new power plants, the amortised capital charge component dominates the cost of PCC integrated electricity generation. In spite of the large reduction in efficiency for Australian power plants when PCC is applied, it appears that reducing the capital costs of PCC will be at least equally important. This is an important outcome for the prioritization of research activities aimed at reducing the costs of capture. For example, the novel solvent development work for improved PCC technology should focus on increasing absorption rates at the same CO2 carrying capacity of the solvent to reduce the capital cost component. [Copyright &y& Elsevier]

Abstract: Post-combustion capture of CO2 is a key technology for the reduction of greenhouse gas emissions from Australian coal fired power stations. It is an emerging technology, which still faces significant challenges in scaling up to full commercial scale suitable for power station applications. To increase adoption by the power industry significant cost reductions in capital and operating cost must be realised. CSIRO has developed an integrated post-combustion capture R&D and pilot plant program aimed at bringing down the barriers for commercial deployment. This paper provides an overview of the program and its status. [Copyright &y& Elsevier]