Why energy efficiency?

Much effort is currently being focused on reducing greenhouse gas emissions from coal-fired power generation. However, it is just as important to reduce the amount of carbon dioxide (CO2) that ends up in the waste flue gas that comes out of the flue stack of a power station. This is done by improving the efficiency of the coal combustion process. It stands to reason that the less coal used per unit of electricity generated, the less CO2 is produced.

One way to support the reduction of the amount of CO2 produced during this process is to improve the efficiency of the steam and gas turbines currently used in the generation process.

These turbines convert the heat released (from burning coal) into power or work, otherwise known as ‘thermal efficiency'. In fact, a one percent increase in thermal efficiency can result in a 2-3 percent decrease in CO2 emissions. This improves the performance of Carbon Capture and Storage programs and reduces the associated economic costs.

Efficiency gains can also be made by developing innovative ways to generate electricity from coal or by reducing the amount of energy (and associated greenhouse gas emissions) required to power specific equipment at key steps in the electricity generation process.

Five projects have been supported by the Fund to drive innovation to improve the efficiency and associated costs of coal-fuelled electricity generation and carbon capture and storage initiatives.

Project: Development and optimisation of the Direct Carbon Fuel Cell

The challenge:

Identifying and developing more efficient ways to generate electricity from coal with significantly less greenhouse gas emissions.

The action:

Coal Innovation NSW funded the University of Newcastle to research and develop a Direct Carbon Fuel Cell.

Grant amount:

$608,719 (EOI Round 2009)  + $1.64 million (EOI Round 2015).

The project:

The University of Newcastle received funding in 2010 to research and develop a Direct Carbon Fuel Cell (DCFC). In a DCFC, electricity is generated directly from coal through the chemical oxidation of coal which has been ground and purified of ash and other contaminants.

This technology is widely promoted as being able to generate electricity with much higher thermal efficiencies (~70-80%) than engines and turbines (~35-55%). The higher efficiencies result in substantial reductions in greenhouse gas emissions. Also, the emissions that are produced are almost pure CO2 so are ready for capture and storage.

This project has been completed and the final report, Development and Optimisation of the Direct Carbon Fuel Cell, contains further details of the project findings.

Fuel Cell

Direct Carbon Fuel Cell Demonstration Pilot Plant (photo courtesy of Prof Scott Donne, University of Newcastle)

Project: A novel chemical looping based air separation technology for oxy-fuel combustion of coal

The challenge:

Increase the efficiency of the chemical looping process in adoption of carbon capture technologies and develop its novel application as energy storage for coal fired power generation.

The action:

Coal Innovation NSW funded the University of Newcastle Priority Research Centre to undertake two projects to investigate a novel way to make coal fired electricity generation more efficient with the chemical looping process.

Grant amount:

$886,618 (EOI Round 2009) + $383,663 (EOI Round 2015).

The project:

The University of Newcastle Priority Research Centre for Energy received grant funding in 2010 to undertake research into a novel way of producing pure oxygen for use in the efficient burning of coal to generate electricity. The technology, termed Chemical Looping Air Separation (CLAS), relies on the principles of ‘chemical looping’ and uses the cyclic interaction of a metallic compound (called a metallic oxide carrier) with air as a means of separating out the oxygen.

CLAS offers the prospect of reducing the greenhouse gas emissions from the air separation processes. It also promises to be a cost-effective way to overcome a major barrier to the adoption of carbon capture technologies such as oxy-fuel combustion (i.e. electricity generation via steam produced by the combustion of coal in pure oxygen rather than air) as conventional air separation is notoriously expensive.

This project has been completed and the final report, A Novel Chemical Looping Based Air Separation Technology for Oxy‐Fuel Combustion of Coal, contains further details of the project findings.

Demo Unit

Seven-metre high demonstration unit (photo courtesy of Behdad Moghtaderi, University of Newcastle)

Project: Energy harvesting from a CO2 capture process

The challenge:

Make post combustion capture of CO2 more commercially viable by reducing the energy requirement.

The action:

Coal Innovation NSW is funding CSIRO Energy to prove a novel process to harvest energy from the CO2 capture process.

Grant amount:

Up to $578,991 (EOI Round 2015)

The project:

CSIRO Energy is receiving grant funding to explore the harvesting of low grade thermal energy by adding an electro-chemical energy conversion step to the conventional carbon capture process. The energy conversion is achieved by the electro-chemical reaction between CO2 and organic liquid absorbents such as ammonia and monoethanoalmine (MEA).

This CO2 capture and energy harvesting process could provide a technological breakthrough for post combustion carbon capture by significantly reducing the additional energy required to capture CO2, thereby making post combustion capture of CO2 more commercially viable.

Energy Harvesting schematic (photo courtesy of Paul Feron, CSIRO Energy)

Project: Direct Carbon Fuel Cell (DCFC) demonstration

The challenge:

Overcome the technical barriers to the commercialisation of Direct Carbon Fuel Cell technologies.

The action:

Coal Innovation NSW is funding the University of Newcastle to research, develop and optimise a 10 kilowatt Direct Carbon Fuel Cell DCFC demonstration unit.

The project:

Building on the previous studies on the DCFC (as mentioned above), The University of Newcastle is receiving funding to build and optimise a world first Direct Carbon Fuel Cell (DCFC) demonstration unit.

This project aims to deliver a technology package capable of being licensed as a 10 kilowatt DCFC module based on laboratory findings and pilot plant optimisation.

The DCFC is not a new concept and the technology has undergone a major boost in international research interest in recent years, however technical barriers have meant commercialisation has not occurred. This project is important because it will bridge a crucial gap between research and commercialisation of DCFC technology.

Project: Combining Redox Energy Storage with coal-fired power generation

The challenge:

Assist coal-fired power stations to better manage their load demands and reduce greenhouse gas emissions with energy storage technologies.

The action:

Coal Innovation NSW is funding the University of Newcastle to develop an energy storage technology termed ‘Redox Energy Storage’.

The project:

The University of Newcastle is receiving funding to develop an energy storage technology termed ‘Redox Energy Storage’ (RES) to help power stations better manage their power load by storing energy in off-peak periods for later dispatch.

The premise is that a RES unit can store large amounts of electricity during off-peak times when electricity demand is low, which can then be supplied back to the grid during peak times when demand is high.

The RES unit has potential to provide flexibility to coal-fired power plants to operate in the cycling mode without disrupting its baseload operation. This would reduce the need for more high cost capital generation equipment for serving times of peak electricity demand only, whilst reducing greenhouse gas emissions.

Energy Storage Pilot Plant (photo courtesy of Behdad Moghtaderi, University of Newcastle)

For further information
Coal Innovation NSW
Phone:
(02) 8229 2919
Rick.Fowler@planning.nsw.gov.au
ccs.info@planning.nsw.gov.au