WA Regions of Interest

Contents

Edition 3, Revised 18/10/2016

Western Australian Electricity Existing and Projected

Western Australia is our largest state with a land area of 2,529,875 square kilometres. It has around 2.6 million people, or 11% of the national population. With its  small isolated population and without any grid connection to the remainder of the nation it has unique challenges in establishing low carbon generation

There are two large electricity markets in Western Australia: the North West Interconnected System (NWIS) and the South West Interconnected System (SWIS). The two systems are not connected electronically. Additionally there is a significant resource sector generating capacity that is not interconnected.

South West interconnected system
North West Interconnected System
North West Interconnected System

Western Australian Generating Capacity

The capacity of these systems in 2014[i] is listed in Table 1

System Rated Capacity 2014 (MW) Main fuel
North West Interconnected System (NWIS) 554 Gas
South West Interconnected System (SWIS) 554 Biomass, Landfill Gas, Solar Photovoltaic, Wind, Wind/Diesel
5440 Coal, Coal/Gas/Diesel, Gas, Gas/Diesel
Non-interconnected systems (Off grid) 3341 CNG/LNG, Diesel, Gas, Gas/Diesel
49 Hydro, Solar Photovoltaic/Diesel, Wind, Wind/Diesel
Total 9937

Table 1 – Western Australian Generating Capacity – 2014

Ninety two percent of the population is concentrated in the south west corner where they receive power from the South West Integrated System (SWIS).

While the state generated a total of 32 TWh of electricity in 2014-15[ii] the SWIS in the south west delivered approximately 18.7 TWh of electricity[iii] or about 59% of the state’s total. In 2011-12 the NWIS generated 2.47 TWh and 6.4TWh in the off grid sector. The numbers vary between years and cannot be reconciled for one complete year.

Peak demands are:

  • SWIS, actual 3,702MW[iv] in 2014 with an anticipation of around 4,600MW by 2024. This becomes 6,700MW in 2050 using the same linear trend.
  • NWIS, No peak value can be found however based on capacity we will assume 500MW in 2014 and say 800MW in 2050.

BREE estimate that Western Australia will increase its 2014 generating total from 32 TWh to 46 TWh. On a proportioning basis, the SWIS and NWIS would grow from 21.17 TWh to 30.4 TWh by 2050

In the SWIS is about 91% of electricity is generated by fossil fuels with coal at about 50% and gas at 41% while in the NWIS the fossil fuel amount is closer to 99%.

Nuclear Energy in Western Australia

Large Reactor Option – Not favoured

If AP1000 sized reactors were used then by 2050 Western Australia would require:

  1. To meet electricity demand based upon annual output of 29 TWh uses 3 reactors while a peak demand of 7,500MW uses at least six reactors. The existing power system is very “peaky” with an average capacity factor on the SWIS of only 36%.
  2. Electrification of light vehicles and some heavy transport would be met by 1.1 reactors.
  3. Transition of manufacturing away from gas and coal to more electrification would require 1.9 reactors.
  4. Linking of the SWIS and NWIS by a 500 Kv transmission system to reduce carbon emissions in the Pilbara region and to meet the needs of a larger grid load.
  5. Substantial upgrade of the SWIS with a 500 Kv transmission system to distribute new large localised generating capacity.
  6. Energy storage possibly in the form of pumped sea water reservoirs. This would be needed to balance the reactor capacity against peak loads. It would also be required to meet the risks of reactor trips and downtime due to refueling.

 

For the purposes of this plan this would require a total of six reactors with a generating capacity of 6.7 GW plus transmission upgrades and energy storage.

This option would incur large costs as a result of trying to “shoehorn” large reactors into a small energy system and is not investigated further at this stage.

 

Small Modular Reactor Option – Better Option

Clearly a small self contained grid such as Western Australia’s will require backup capacity to cope with reactor trips and refuelling. Smaller reactors in the sub 300MW class such as the proposed SMR’s would be a better fit. They would overcome the impacts of refuelling or reactor trips and would mean that the grid would not require such extensive upgrades and energy storage can be avoided.

Unfortunately SMR’s are not currently available. Significant development is taking place in the USA, UK, China, Russia and South Korea.

Currently one of the more advanced SMR’s being proposed and closer to licensing approval is the Westinghouse 225MW SMR. The business case for SMR’s is reliant upon mass modular construction, a significant order book and at least two decades to availability.

If 225MW small modular reactors were used then by 2050 Western Australia would require:

  1. To meet electricity demand based upon meeting 80% of the annual output of 29 TWh uses 14.7 reactors. Meeting 80% of a peak demand of 7,500MW uses at least twenty seven SMR’s. The existing power system is very “peaky” with an average capacity factor on the SWIS of only 36%.
  2. Electrification of light vehicles and some heavy transport would be met by 5.4 reactors.
  3. Transition of manufacturing away from gas and coal to more electrification would require 10.9 SMR’s.
  4. Linking of the SWIS and NWIS by a 220kV or 330kV kV transmission system.
  5. Selective upgrade of the existing SWIS 275kV and 330kV transmission system.

For the purposes of the plan we will work with a total of 31 SMRS with a generating capacity of 6.98 GW.  The following table shows seven regions of interest that could contain these reactors.

NWIS region for Small Modular Reactors

NWIS region for Small Modular Reactors

 

South West regions of interest for small modular reactors

South West regions of interest for small modular reactors

Regions of Interest in Western Australia

Region of Interest Location Feature Siting Cooling Comment
1 Geraldton Region Coastal  or Inland Stable rock foundations Once through sea water or hybrid air/water cooling Grid upgrade required.

Assumes minimum plant size 2 x 225MW SMR’s = 450 MW

2 Perth Region Coast and Inland

Replacing Kwinana, Cockburn and Pinjar Generators – 1642MW replaced

Stable rock or non rock foundations Once through sea water or hybrid air/water cooling Grid upgrade required. Assumes minimum plant size 12 x 225MW SMR’s = 2700MW
3 Collie Region Inland Stable rock foundations Hybrid wet/dry process. Modest grid upgrade, close proximity to existing Collie region power stations. Assumes minimum plant size 9 x 225MW SMR’s = 2025MW
4 Kemerton Replace Wagerup Gas Power station Stable rock or non rock foundations Hybrid wet/dry process. Assumes minimum plant size 2 x 225MW SMR’s = 450 MW
5 Margaret River Coastal Location, requires extensive grid upgrade Stable rock foundations Sea water cooling Assumes minimum plant size 2 x 225MW SMR’s = 450 MW
6 Albany Coastal Location, requires modest grid upgrade Stable rock foundations Sea water cooling Assumes minimum plant size 2 x 225MW SMR’s = 450 MW
7 Carnarvon Basin/

Pilbarra

Coastal Location, requires modest grid upgrade locally and large interconnector to SWIS Stable rock foundations Sea water cooling Assumes minimum plant size 3 x 225MW SMR’s = 675 MW

[i] WA Dept of Finance – Generation website

[ii] Australian Energy Projections, Bureau of Resources and Energy Economics

[iii] Table 8 Sent Out Energy Forecasts, SWIS Electricity Demand Outlook, Independent Market Operator

[iv] Fig 30, Sent Out Energy Forecasts, SWIS Electricity Demand Outlook, Independent Market Operator

Cooling WA Nuclear Plants

In Western Australia coal fired plants were constructed adjacent to available coal mines and other infrastructure.
New nuclear plants will where possible take advantage of the resource used for cooling at these plants.
In an effort to reduce the environmental impact upon inland water resources, modern nuclear power plants are being designed to use a hybrid system of air and water cooling. During periods of low water availability the degree of air cooling can be increased though at a modest reduction in power output.
At coastal plants such as those in the Geraldton, Perth, Pilbarra, Margaret River and Albany regions, sea water would be the sole form of cooling.

The tabulation shows the anticipated type of cooling at each plant

Western Australia’s long coastlines provide many options for locating nuclear power plants

While recirculating systems don’t add heat to the river or lake, they do consume water through evaporation. In Western Australia the availability of sizeable inland rivers are limited and so to overcome issues surrounding temperature rises in inland locations  mechanically driven systems known as  hybrid and recirculating systems can be used. These are now the only option used in the United States under their EPA guidelines.

An excellent and detailed outline of the cooling options is available at: Cooling Power Plants | Power Plant Water Use for Cooling – World Nuclear Association

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