## 5 Example Analysis
### Analysis of the Simulation Results
#### 5.2.4 Optimal Dispatching Scheme of the Lower Micro-Energy-Grid Level  
The electrical load (a) and heating load (b) dispatching schemes of the micro energy grid, for a typical day in the winter when the distribution network comprising the micro energy grid was in the optimal dispatching state, are shown in Figure 12. In Figure 12a, when PV and wind power could generate electricity, PV and wind power were at full power at the predicted output power, satisfying a portion of the energy needs of the micro energy grid. In the valley period of the electricity price, between 11:00 p.m. and 07:00 a.m., the microturbine did not work because the price of gas was higher than the electricity price of the power grid. Simultaneously, electricity was bought from the distribution network to satisfy the load demand, and to charge the battery. In the flat or peak period of  
Figure 11: Optimal dispatching schemes of the distribution network comprising the micro energy grid on a typical day in the winter (**a**), and in the summer (**b**). the electricity price, between 07:00 a.m. and 11:00 p.m., the electricity load of the micro energy grid was satisfied by the microturbine, the discharge of the battery, and PV and wind power because the electricity price of the power grid was higher than the price of the gas. The surplus electricity was also sold to the distribution network to obtain income. During the entire running period, the battery was charged in the valley period, and discharged in the peak period, playing the role of peak load shifting in the micro energy grid, and reducing the operating cost of the micro energy grid. In Figure 12b, the gas-fired boiler, heat-recovery boiler, battery storage, heating storage tank, and air-source heat pump jointly bore the supply of the heat load. In the valley period of the electricity price, between 11:00 p.m. and 07:00 a.m., the electricity price was low, and the air-source heat pump worked at full power. If the heat-recovery boiler and air-source heat pump could not satisfy the heat load, then the surplus heat-load demand was satisfied by the gas-fired boiler, and the heating storage tank was charged. In the flat or peak period of the electricity price, between 07:00 a.m. and 11:00 p.m., the electricity price was high, and the heating load was satisfied by the heat-recovery boiler, and the heat storage tank. Figure 12: Electrical load (**a**) and heating load (**b**) dispatching schemes of the micro energy grid for a typical day in the winter when the distribution network comprising the micro energy grid was in the optimal dispatching state. The electrical load (a) and cooling load (b) dispatching schemes of the micro energy grid, for a typical day in the summer when the distribution network comprising the micro energy grid was in the optimal dispatching state, are shown in Figure 13. In Figure 13a, because the load in the summer was less than the load in the winter, three microturbines were used in the summer, and the one remaining microturbine was overhauled. Similar to Figure 12a, when PV and wind power could generate electricity, PV and wind power were at full power at the predicted output power. In the valley period of the electricity price, between 11:00 p.m. and 07:00 a.m., the electricity was bought from the distribution network to satisfy the load demand, and to charge the battery. In the flat or peak period of the electricity price, between 07:00 a.m. and 11:00 p.m., the electricity load of the micro energy grid was satisfied by the microturbine, the discharge of the battery, and PV and wind power. Then, the surplus electricity was sold to the distribution network to obtain income. The battery storage played the role of peak load shifting in the micro energy grid. In Figure 13b, the lithium-bromide absorption-type refrigerator, cooling storage tank, and air-source heat pump jointly bore the supply of the cooling load.