Research On Optimization Models Of Comprehensive Energy Saving Of Power Industry Chain Under Power Prices

Power is one of the main constitutions of energy and has great effect on energy supply security. Energy saving of power industry has been one important way for relieving the energy supply shortage pressure. Through the implementation of energy-saving dispatching, generation right exchange, TOU(time-of-use) power price, and resident multi-step power price, which improve the proportion of clean energy power generation and power generation structre, and reduce the consumption and losses of power, positive results have been achieved in energy saving in each part of power generation, power transmission and distribution, and power demand side. However, as each part of the power industry chain pays more attention on their own benefits when carring out energy-saving policies, it is difficult to realize overall coordination and cooperation of the whole power industry and achieve the optimal energy-saving benefits. How to coordinate the energy conservation measures of all participants of the power industry chain to achieve the synergy and amplification of their energy saving benefits have been a key point in the research and implemetaion of power energy-saving policies. Based on above background and current electricity market mechanism, this dissertation studied the comprehensive energy saving methods and optimal models of power industry chain that are electricity price-oriented, and providing theoretical reference for improving the coordination in each part. Based on the power industry chain, this dissertation studied the optimization models and methodology of combined energy savings in power generation, power grid and demand side under the prices in each part of power generation, power transmission and distribution, and power demand side, and designed to provide theoretical reference for the implementation of energy saving policies in power industry chain of China.For the optimization of energy saving in power generation side, this dissertation focused on the optimization models of energy saving in power generation and electricity-coal transportation. Three energy saving optimization models for combined dispatching of multi-type generation units, including wind power generation untis, PV power generation units, hydro-power generation units, and thermal power generation units, were built based on different dispatching polices:the purchasing of electricity generated by renewable energy in full amount, restriction of wind power output, and the joint operation of hydropower and thermal power generation. The combined model includes wind power, photovoltaic power, hydropower, and thermal power. This dissertation studied the effect of dispatching methods on power output and coal consumption in each type of unit with a given load demand. The results showed that energy-saving generation dispatch of multi-type units based on an adjustable standby power combined hydropower with thermal power will achieve a better balance between energy-saving effect and economic operation of power system. An optimization model of energy-saving and emission-reduction for generation rights trade is built. Energy-saving benefits from power rights trade can be allocated among the participants with Shapley-value method. Incremental profit and generation exchange price can be fixed based on the contribution rate of energy-saving. For the optimization of coal transportation, this dissertation established a dynamic optimization model of coal supply and transportation route with a single generation enterprise, and a combined optimization model of coal transportation network. An analysis of energy consumption differences in coal transportation brought by the change of coal demand has been taken in the dissertation.For the optimization of energy saving in power grid side, this dissertation focused on the coal consumption increment and share policy from the transmission congestion management. For the optimization of transmission congestion management, this dissertation introduced GSDF (generation shifted distribution factor) based on DCOPF theory. With the target of the minimum coal consumption increment, an optimization model for the energy-saving in transmission congestion management was built without considering load curtailment. Based on equal and opposite quantity in pairs of comprehensive coal consumption equivalent to solve a numerical example. The result showed that the cost of coal consumption increment in transmission congestion is decreased. The coal consumption increment was allocated in the congestion route based on Aumann-Shapley value method. This dissertation built a price design model of power transmission guiding price based on the energy marginal value. Providing theoretical reference for the development and extension of power transmission line, and guiding the power consumption structure and generation investment.For the optimization of energy saving in demand side, this dissertation built a strategy optimization model of distributed power generation system with an adjusted output by taking the distributed combined cycle gas plant as an example. Analyzing the effect of peak load dispatching and electricity price on distributed power generation. Based on the analysis of distributed power generation output, this dissertation built an optimization model of combined energy-saving in congestion management by introducing the outage threshold price of interruptible load. This model takes the distributed generation in the demand side and interruptible load into consideration and then studies the combined energy-saving optimization of power generation, power transmission and power demand. Moreover, for the tiered pricing, this dissertation built an optimization model of electricity price, which aimed at a maximum coal savings. An analysis of the effect of different gradation and different generation structures on the energy-saving optimization of power generation has been taken in the dissertation. For the inner operating mechanism of comprehensive energy saving in the power industry chain, this dissertation establishes a price-oriented system dynamics model of comprehensive energy saving in the power industry chain. Describing the response operation mechanism between each part through causal loop and flow-stock diagram, and simulate the variation trend and coal-saving effect under the comprehensive function of power industry chain by Vensim. The result shows that, the effect of demand side response of increasing sale price will lead comprehensive energy savings in power industry chain. By increasing sale price and rolling the proceeds into transmission capacity construction, and the compensation of clean energy, it will decrease the power transmission congestion cost and coal consumption. However, the effect of demand response will decrease progressively over time. A long-term adjustment mechanism of sale-price-oriented demand side management is needed.