Geothermal Energy Utilization In South Australia

The History of Electricity in Melbourne

Discuss About The Geothermal Energy Has Utilized Commercially.

The first electricity to be supplied in Melbourne was generated and distributed by a number of private companies and municipal generators. At first, the electricity produced in Victoria using simple technology and transmission was done over short distance hence it was being used for public events. In the current situation, most electricity is generated by burning coal brown in color and the major consumers of electricity in Victoria is aluminum smelter at Portland. The high water content in coal makes it less suitable for combustion unless a specialized technology is used and Victoria has a limited hydroelectric generation system due to limited water resources. There is a wind farm in Victoria having 250 wind turbines and producing 8000GWh of electricity which represents 18% of the power used in Victoria

The first electricity to come to Alice Springs was in 1872 in the form of 120 volts’ batteries that was being used in operating the Overland Telegraph Line. The first Alice Spring was situated in Bath Street and the second station was in Sadden Range. Alice Springs receives a solar radiation of about 6.16-kilowatt hours per square meter daily. The following are reading from the weather station report

• Wind speed in Alice Spring: 4.56m/s
• Solar radiation: 6.16kWh/sq. m/day
• Humidity: 39.42%
• Air temperature: 20.86 degrees Celsius.
• Air pressure: 95.29kPa

• 8128kWh is the average output produced by the system daily.
• The minimum output on a daily basis is 5.8374 kWh.
• The maximum daily output is 11.043 kWh.
• The value of electricity annually is $ 965.

There are factors that affect the output of solar PV system for example;

• The thickness of the cable since in case a cable of 6 sq. mm cross section cable will now be 0.06 ohms and the voltage drop, o.6V which is 2.5 % voltage drop for a 24V system which might be acceptable. The size and thickness of the cable need serious attention starting from the planning stage. System voltage can also be raised in order to reduce the resistance loss.
• Temperature also affects the output of solar PV since solar perform better in cold rather than in hot climate. Panels conventional at 25 degrees Celsius and the rise in temperature above 25 degrees’ Celsius decays the output but in hot summer days, the temperature of the panel reach 70 degrees and this means the panel will put out up to 25% less power compared when rated at 25 degrees.
• Battery efficiency also determines the output since they are needed for charge storage.

• Photovoltaic panels ( PV panels)
• Inverters
• Meters
• Charge controllers
• Disconnect switches
• Battery banks to store the solar power
• Fuse
• Surge protection that the government requires being installed

According to the report released by the AEMO on the blackout which occurred in South Australia; It was justified that the blackout was a result of wind which blew over the transmission line but has nothing to do with the South Australia wind turbines. In the report, it has been well articulated that on the day of total grid failure, two electrodes having a speed of wind of 190 and 260 kilometers per hour tore through a single circuit 275kV transmission line around 170km apart. The damaged of the three transmission lines tripped resulting to six voltage dips on the South Australia grid in a short period of time (Ackerman, 2012, p. 345).

A sustained power reduction was experienced in nine wind farms situated in mid-north of South Australia as the fault on the transmission network grew. The protection settings allowed the wind turbines to withstand a preset number of voltage dips within a period of two minutes. The output of the wind farm fell by 456 megawatts immediately the protection feature kicked in (Belyaev, 2010).

The reduction of output in the wind farm made the Heywood Interconnector from Victoria to try to make up the shortfall. After the powering down of the last wind farm, the interconnector flow attained a level that it activated a special protection scheme which tripped it offline. The generation remaining was much less than the connected load resulting to the collapsed in the entire system. The power system of South Australia then became separated from the national grid. In relation to the statement made by political leaders, AEMO reports show that there is no doubt the protection settings on some windfarms also contributed to the chain of events which resulted in a statewide power blackout.

Electricity in Alice Springs

According to the report presented by the AEMO, the blackout was caused by overprotective wind turbine settings being triggered thus causing a reduction in power generation. The primary reasons which caused loss of power in South Australia were (Dong, 2016, p. 123);

• Two tornadoes damaged 275kV transmission line and a double circuit 275kV transmission line simultaneously.
• The damage made transmission line to trip resulting in six voltage dips on the South Australia grid within grid-connected two minutes.
• The number of voltage dips triggered a protection feature to be activated on eight wind farms in South Australian.
• The activation of these features resulted in significant sustained generation reduction of 456 megawatts over a period of seven seconds(Hordeski, 2008, p. 223).
• The rapid increase in flow through the Victoria-South Australia interconnector activated a protection scheme which tripped interconnector offline.
• South Australia became separated from the National Electricity Market and the generation which remained was outweighed by the loads connected and therefore the frequency of the island could not be maintained thus all supply to South Australia was lost(Luis, 2013, p. 432)

Adjusting potential settings in wind turbine assist in preventing shocks which occurs in case of bad weather. Potential settings assist in the wind farm assist the wind farm to override the voltage disturbance in case of a storm.

In the South Australian power failure, there were issues with Synchronous generators and they included;

• It was expected that all generators should have been able to ride through the transmission faults caused by the storm.
• It was noted that the five thermal generators operating as transmission lines fell, remained connected and operated up until the South Australia system disconnected from the rest of the National Electricity Market.
• The operation of these generators relying on the system faults experienced during these events(Moore, 2017, p. 345).

There were numerous issues in the level of inertia and they include;

• At the present, there was enough inertia available for conventional generators which is accessible to all the areas connected synchronously in order to assist in maintaining the security of the system and attaining the set frequency standards.
• The reduction in the operation of synchronous generation became more likely as a result of low level of inertia. This included the areas during the time of low demand and high renewable when the conventional generation is offline.
• The material technical difficulties for the power system microgrid generally resulting from the changing generation mix(Plimer, 2017, p. 47).
• South Australia will need to run as an islanded system, replying to local generations to provide the needed services.
• Tasmania cannot access mainland inertia whereby low inertia is more likely occur in case of low demand. Hydro generation is likely to be withdrawn from the market as a result of the capability of their flexible operation and renewable status, unlike conventional gas and coal, fired generation.
• The electrical frequency stays the same across the whole grid while the national grid stays stable and intact. The generators synchronized to the system contribute to the inertia found in the grid in general

The level of inertia plays numerous role in the operation of power system. Inertia is just a function of the mass of the rotors of conventional generators. The inertia of conventional generators acts to resist changes taking place rapidly in power system frequency. Inertia acts to dampen the act at which frequency can change on the whole power system. The power system frequency is slowed if the amount of inertia in power system is greater and the response to a particular disturbance for example trip of generating unit depend on it (Wang, 2015, p. 97).

There is an implication in power system security resulting from an increase in the rate of change of frequency because traditional control system for example under frequency load shedding and contingency frequency control ancillary services might not respond quickly enough to arrest and contain a frequency disturbance. Under normal and abnormal circumstances, reduced power system inertia becomes difficult to manage and that is why there is need to carry out a technical analysis. The conventional generators were provided so the availability of the services are affected by the operational generators. The shortage of power system in South Australia may come as a result of the withdrawal of conventional generations (Spoehr, 2009, p. 100).

Inertia can be provided by the traditional synchronous generators, for example, hydro generators, coal and thermal gas.

The possible supporting role could local DG and local distributed energy storage had in preventing or at least minimizing loss of supply.

The Distributed Generation (DG) is a new concept in electric market and it has been used for decades in electricity in the electricity market. It is simply powered generation built near consumers and its sources include small-scale, environmentally –friendly such as wind and photovoltaic installed and designed to preserve a single end users site. Distributed Generation mostly comprises traditional fuels fired reciprocating engines or gas turbines. The Distributed generation plays numerous roles in minimizing or preventing loss of supply for example;

• The size of the turbine is increased while the marginal cost of production of electricity is decreased as a result of advert of the steam turbine. In simple terms, DG has an advantage on economies of scale point of view(Luis, 2013, p. 23).
• The Distributed Generation enable transmission of electricity. The alternate currents are used unlike direct current and they are allowed to transmit over long distances without a significant reduction or loss.
• High efficiency and this was achieved via larger facilities which are capable of withstanding a lot of pressure from the steam and the temperature used in the generation of electricity.
• The environmental constraints. The generation facilities outside the city center were relocated by the use of network transmission and this led to the removal of pollution due to coal fire plant exhaust.
• Distributed Generation increase reliability of the electric system
• It supplies the power demanded urgently.
• It reduces the effect of using the land.
• It assists in the reduction of vulnerability.
• It assists in peak power reduction.

Factors Affecting Solar PV Systems

Energy storage has played a Microgrids role in the electricity industry known and the most commonly used type of energy storage in Australia is the use of pumped hydroelectricity storage with 1490MW of operation within Australia. The local distributed energy storage plays the following roles in Australia;

• Ensuring the electricity produced is stable and of quality.
• Reducing the need for new transmission power plants and lines.
• Smoothing the supply of the generated electricity from variable renewable energy sources.
• Decreasing the reliance on combustion power plant to meet peak demand.
• Providing security to the grid where there are transmission and distribution interruption.
• Enhancing grid efficiency by dispatching energy in case the electricity is needed rather than when it was originally generated.
• Managing short-term differences caused by demand for energy and fluctuation in the generation.
• Distributed energy storage can be used to defer or offset the need for new generation capacity.
• They can be used in providing the backup source of power supply.
• Local distributed energy sources can be used in Australia to dampen fluctuations of voltage on the distribution lines.
• They can be used in shifting energy through time to reduce the cost of generation by storing excess electricity at off-peak times and discharging during peak periods.
• They are used also in case of line outage.

Microgrids also are known as hybrid generation systems or remote power systems or mini-grids are self-contained electricity which is capable of operating independently of it and they range in size from kilowatts to megawatts. Microgrids are the outcome the massive changes taking place in the electricity market including, distributed energy resources, energy storage system and plug-in electric vehicles. Example of electricity microgrid applications include;

• Research facilities such as campuses
• Military installation
• Remote, island or rural communities
• Industrial or commercial facilities such as data centers

• Microgrid assists in technology cost reductions because according to electricity market in Australia the cost of monitoring and controlling renewable energy technology are reducing.
• It enhances clean and affordable energy for economic development.
• Use of microgrid promotes the use of renewable energy and acceptance of localized energy solutions.
• The microgrid provides a cost-effective solution to promoting system resilience in the face of Australia by increasing vulnerability to environmental hazards

As a result of the national transmission grid, South Australia leads the nation in terms of renewable energy commercialization with 8% of the nation’s population. It captures 90% of its geothermal developments, 30% of solar power and 56% of the grid-connected wind power. South Australia is also considered to be the target for green energy investors. South Australia and Tasmania are the granite basement rocks are suitable and they are main locations where geothermal energy is being developed in Australia The geothermal energy has been utilized commercially at two locations in South Australia that is Birds Ville which generates geothermal electricity from hot water from the great artesian basin and also geothermal district heating scheme at the Portland. Implications of national transmission grid resulted in many companies in Australia engaging in developing geothermal energy in full scale for full-scale commercial deployment (Kariniotakis, 2017, p. 87).

The implication of national grid has led to the spread of Distributed Generation (DG) locally such that currently, the lithium-ion battery installation is taking place outside Horns dale wind farm in South Australia. South Australia is also planning to build a 250MW virtual power plant which will entail thousands of solar panels and battery running software that decides when the batteries charge and discharge in order to maximize the value and efficiency of the grid (Hordeski, 2008, p. 17).

References

Ackerman, T., 2012. Wind Power in Power Systems. s.l.: OLMA Media Group.

Belyaev, L., 2010. Electricity Market Reforms. s.l.: Hauffe Gruppe.

Dong, Z., 2016. Emerging Techniques in Power Systems Analysis. s.l.:Informa.

Hordeski, M., 2008. Emergency and Backup Power Sources. s.l.: Thomson-Reuters.

Kariniotakis, G., 2017. Renewable Energy Forecasting. s.l.: Adventure Works Press.

Luis, D., 2013. The Australia & New Zealand Grapegrower & Winemaker. s.l.: Ridders Digest.

Moore, T., 2017. Urban Sustainability Transitions. s.l.: McGraw-Hill Education.

Plimer, I., 2017. Climate Change Delusion and Great Electricity Rip-off. s.l.:HarperCollins.

Spoehr, J., 2009. The Electricity Crisis. s.l.: Wolters Kluwer.

Wang, N., 2015. Large- Scale Wind Power Grid Integration. s.l.: China Publishing Company.