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Electricity, Electromagnetic fields, Enlightenment, Heat, Telegraph, Electricity, Electromagnetic fields, Enlightenment, Heat, and Telegraph

Audio recording of session B14 of the March 2016 annual meeting of the American Physical Society, held in Baltimore, Maryland in March 2016. This session was chaired by Amy Fisher, University of Puget Sound. Talks (and speakers) include: "Electrical Enlightment: Joseph Priestley's Historical and Experimental Studies of Electricity" (Victor Boantza); "Lomonosov's Electrical Experiments" (Robert Crease); "Priestley's Shadow and Lavoisier's Influence: Electricity and Heat in the Late Eighteenth and Early Nineteenth Centuries" (Amy Fisher); "Broken Circuits? International Scientific Communication on Galvanic Electricity During the Napoleonic Wars" (Iain Watts); "The Bottom Line: Cable Telegraphy and the Rise of Field Theory in the Victorian British Empire" (Bruce Hunt). Topics discussed include Joseph Priestley; electricity; the Enlightenment; Mikhail Lomonosov; Antoine Lavoisier; relationship between heat and electricity; telegraphy; electromagnetic field theory.

Electricity, Emissions, Externalities, Greenhouse gases, Nuclear, Pollutants, and UCTD

Acid rain, Carbon dioxide, Climatic changes, Electricity, Environmental sciences, Political planning, Interviews, Oral histories, and Transcripts

In this interview Dick Bratcher discusses topics such as University of Michigan, State of California Water Resources Control Board, Wisconsin Electric Power Company, Electric Power Research Institute (EPRI), environmental science, public policy, electricity, climate change, Richard Richels, carbon dioxide emissions, Peter Mueller, Chuck Hakkarinen, Model Evaluation Consortium for Climate Assessment (MECCA) project, and acid rain.

Acid rain, Carbon dioxide, Climatic changes, Electricity, Environmental sciences, Political planning, Interviews, Oral histories, and Transcripts

In this interview Dick Bratcher discusses topics such as University of Michigan, State of California Water Resources Control Board, Wisconsin Electric Power Company, Electric Power Research Institute (EPRI), environmental science, public policy, electricity, climate change, Richard Richels, carbon dioxide emissions, Peter Mueller, Chuck Hakkarinen, Model Evaluation Consortium for Climate Assessment (MECCA) project, and acid rain.

Acid rain, Carbon dioxide, Climatic changes, Electricity, Environmental sciences, Political planning, Interviews, Oral histories, and Transcripts

In this interview Dick Bratcher discusses topics such as University of Michigan, State of California Water Resources Control Board, Wisconsin Electric Power Company, Electric Power Research Institute (EPRI), environmental science, public policy, electricity, climate change, Richard Richels, carbon dioxide emissions, Peter Mueller, Chuck Hakkarinen, Model Evaluation Consortium for Climate Assessment (MECCA) project, and acid rain.

Short circuits, Electricity, Electricity, and Short circuits

The transmission network expansion may cause a power system at risk of high short-circuit current level. This thesis presents transmission network reconfiguration algorithm by bus splitting to limit short-circuit current to less than the interrupting capacity of the circuit breakers. Standard rules of bus splitting are developed with regard to the feasibility in practice. The proposed algorithm determines suitable pattern of the bus splitting while minimizing the number of buses to be split. Then, the impact on voltage stability of the system will be evaluated through PQ voltage stability index (PQVSI). The proposed solution has been tested on the actual transmission system in Thailand, considering the short-circuit currents only at the 21 high voltage stations in the metropolitan area. When comparing to other techniques proposed earlier, the test results show that the proposed method gives less impact on the system security with respect to the computed PQVSI.

Buildings -- Energy consumption, Electricity, Electric power, Buildings -- Energy consumption, Electric power, and Electricity

Combined Cooling Heating and Power (CCHP) can be applied to energy management system in buildings to increase the efficiency of primary energy consumption, as well as to reduce the carbon dioxide emission. This thesis proposes an algorithm to determine optimal hourly scheduling of the CCHP system for building load. Heat storage tank and photovoltaic system are also incorporated into energy management system. The objective function is to minimize total operating costs with the constrains of equipment operating limits and energy balance conditions. The formulated problem is solved by the Linear Programming. The determined operating conditions are displayed on the Graphic User Interface (GUI) to assist the operator to operate such system. Performance verification of the proposed building energy management has been done using power demand of one shopping complex. The results show that the total cost of electrical and cooling energy decreases by 12% per year, and increase to 40% when additional income from selling the surplus cooling water is considered.

electricity and renewable energy sources

Solar cells, Electricity, Short circuits, Electric circuit-breakers, Electric relays, Electric power systems -- Protection, Electric circuit-breakers, Electric power systems -- Protection, Electric relays, Electricity, Short circuits, and Solar cells

This thesis proposes the anti-islanding method for distribution systems with Photovoltaic Generation System (PVGS) by using voltage and frequency relays. This thesis derives Non Detection Zone (NDZ) of Over/Under voltage and Over/Under frequency ranges by using load quality factor in order to increase the accuracy for islanding prevention. In addition, another method to prevent islanding situation is derived by using Newton-Raphson's power flow. The islanding prevention is considered necessary for the currently increasing Photovoltaic Generation Systems. In addition, the thesis proposes the protective device placement for system reliability improvement by using Genetic Algorithm (GA) optimization. The optimization also takes the account of islanding prevention as a constraint. The proposed method is brought to apply with RBTS Bus 2 distribution system, and a modified system of the Provincial Electricity Authority (modified Banlen system).

Electricity, Electric currents, Power resources, Electric currents, Direct -- Power supply, Electric currents, Alternating -- Power supply, and High voltages

This thesis presents the prototype of AC voltage supply which can be controlled the frequency in the range of 10 - 500 Hz from DC power supply. This uses to supply the power for high voltage electrical equipment with high capacity load such as underground high voltage cable or GIS etc. Using the AC output voltage through the resonance transformer for increasing the voltage up to 5 kV. Typically, the test system of electrical equipment on-site with 50 Hz is large, the transportation of the testing device is quiet difficult. This test system can be adjusted the frequency of AC output voltage to fit with resonance frequency with the test equipment. This reduces its primary current and size. The results from the test system can be used with the capacitor between 600pF and 48.2nF at testing voltage of 5kV. It is given the resonance frequency at 333 Hz and 45.5 Hz and provide the minimum currents from AC power supply at 637.7 mA and 3.1743 A, respectively.

Electricity, Genetic algorithms, Electricity, and Genetic algorithms

Transmission Expansion Planning (TEP) is a process of selection of transmission construction plans to meet growing demand in the future. The selected construction plan must have the lowest total cost while maintaining the ability of the transmission system to securely transfer power. Mathematically, TEP is classified as a Mixed Integer Nonlinear Programming problem (MINLP). This problem combines difficulties of both nonlinear programming and integer programming together. Considering planning period, TEP can also be divided into 2 problems, i.e. single stage planning which does not consider change of demand and multi stage planning where demand growth is taken into account. Genetic Algorithm (GA) is one of the techniques to solve the optimization problem which is suitable for handling the MINLP. In this thesis, the GA is used to solve multi stage transmission expansion problems. The TEP considering in this thesis comprises construction of transmission lines, and installation of shunt reactive compensators. In addition, system voltage stability constraint is also considered through the PQ-Voltage Stability Index (PQVSI). All the TEPs in this thesis are formulated using AC models. The proposed method has been tested with the modified-Garver 6-bus and the IEEE-RTS79 test systems. Satisfactory results were obtained.

Climatic changes, Electricity, Energy policy, and Renewable energy sources

Reducing greenhouse gas (GHG) emissions from the electricity sector will be a central part of Australia's efforts to make deep cuts in its national emissions. This is because the country has high electricity GHG emissions. In tum, renewable electricity (RES-E) is likely to play a major part in cutting Australia's electricity sector emissions because it is less·resource-constrained, and more mature, than the alternative low emission electricity techologies of fossil-fuel carbon capture and storage and next-generation nuclear technologies; Because RES-E generation is currently dearer than fossil-fuel-generated electricity (even given a politically likely carbon price), support mechanisms are needed to allow it to compete with fossil-fuel-generated electricity. In this thesis I show that there is a case for providing support to RES-E in Australia, above that likely to be provided by carbon pricing; and that currently high-cost solar and geothermal types of RES-E should receive more support than currently low-cost RES-E types. The thesis also shows that the largest 2020 GHG reduction target being considered by the Australian government will make only the least expensive type of RES-E (wind) competitive with coal generated electricity, and will not make other RES-E types competitive with it; In the thesis I examine the lessons Australia can learn from the overseas experience of RES-E support policy, particularly in Western Europe and the USA. The thesis specifically examines the generation and subsidy price performance of Renewable Portfolio Standard (RPS) RES-E support mechanisms (where governments determine how much RES-E will be generated and RPS tradable certificate markets determine its price), and Feed-in Tariff (FIT) support mechanisms (where governments determine RES-E prices and electricity generation markets determine how much will be generated), in the USA, eight Western European countries and Australia. I also examine RES-E subsidies provided by the federal government in Australia as well as electricity transmission in the country compared to Europe and the USA. I show that Australia has modest transmission levels, which hinders the development of its RES-E. The cost of transmission expansion in Australia is large, and may need financing across all electricity consumers. It may also need some government subsidisation, and regulation, if market-based transmission planning is not effective; The thesis's analysis of Australia's RES-E development, compared to that of the European Union and the USA, shows that RES-E has a lower electricity generation share (including a lower non-hydro RES-E generation share), and is less diverse, in Australia than in the other two regions/countries. I also show that Australia's current level of RPS RES-E subsidy compares poorly with equivalent levels of wind and solar subsidisation in Germany, Spain and the UK; Two major conclusions in the thesis, which together form its most significant contribution to knowledge, are that radical RES-E expansion (rapid increases in RES-E generation share) will require RPS mechanisms to adopt some features normally found in FITs. The most important of these are 'type-specific support' (different levels of subsidisation for different types of RES-E), and a high level of RES-E investor certainty about subsidy levels. Achieving radical RES-E expansion will also require FITs to adopt features normally found in RPSs, the most important of which are a high level of generation outcome certainty and a close connection between subsidy levels and electricity generation performance. However, the extent to which the RPS and the FIT can be hybridised will not be known with certainty for another three to four years. Until then, recently established RPS banding (variable traded certificate multipliers), as used in the UK and Italy, carveouts (RPS submarkets dedicated to a particular type of RES-E), as used in the USA, and flexible FIT degression (subsidy reductions linked to RES-E generating capacity changes), as used in Germany and Spain, will not have reliable generation and price histories; Institutional inertia means the RPS will very likely remain the main form of RES-E support in Australia, so the need I have shown for an RPS to adopt features normally found in FITs means that banding should be introduced into its RPS, so that it gives different levels of subsidisation for different RES-E types (particularly for solar and geothermal electricity). It also means that an implicit or explicit price floor is needed to make RPS tradable certificate prices less volatile than at present; Comparison of particular features of Australia's RPS with the equivalent features of the RPSs used in the USA and Western Europe reveals other major flaws in Australia's RPS. To remedy them, the thesis also makes the case that pre-RPS RES-E generation should be removed from Australia's RPS; banking of its tradable certificates should be restricted in it; unusual energy sources (especially solar hot water heaters) should be removed from it; and its target should be a generation share, not an absolute quantity of generation. In the thesis I also show that if Australia is to make deep cuts in its GHG emissions, its RPS target needs to be significantly increased so that it at least absorbs all the projected increase in Australian electricity demand. I also recommend in the thesis that Australia's different state and territory FITs be replaced with a national gross FIT for small to medium scaled RES-E, differentiated according to location; In general, I find that while Australia has made a reasonable start in its RES-E development, significant redesign of its RPS is needed if the country is to make deep cuts in its electricity generation GHG emissions through radical RES-E expansion.