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Optimizing thermal–electric load distribution toward combined heat and power (CHP) units can improve the efficiency of thermal power plants. Here, a thermal–electric load distribution method is proposed based on the energy consumption characteristics of CHP plants. The influence of operation modes on the energy consumption characteristics has been considered. Based on the energy consumption characteristics, the influence of load distribution on the heat rate is expounded considering two units operating in parallel. Firstly, a 600 MW unit model is developed using the EBSILON software, and the associated energy consumption model is established by passing the simulation results to a MATLAB routine. Then, three distribution methods are used to study the influence of the thermal–electric load distribution on the heat rate. Finally, the energy consumption model is embedded into a momentum particle swarm optimization (MPSO) algorithm, and the thermal–electric load distribution is optimized using the load data from a characteristic day with the operation feasible region taken as the boundary. The results show that the thermal load plays a major role in the energy efficiency of the unit, and the electric load determines the exergy efficiency distribution. The operation mode of the unit has little influence on the energy utilization rate, but has a significant influence on the exergy efficiency. When two CHP units are running in parallel, their heat rate can be reduced by optimizing the thermal–electric load distribution. A more uneven distribution of thermal–electric load between units results in a lower heat rate. The optimized heat rate given by the MPSO algorithm for a characteristic day is 6887.93 kJ·kWh−1, which is 304.44 kJ·kWh−1 less than under the average thermal–electric load distribution. These findings may be helpful to get insight into the energy consumption characteristics of CHP plants and guide for its economic operation.

Regional integrated energy system has been a suitable scheme in China to satisfy eco-industrial park’s both electric and heat needs. Combined heat and power (CHP) is an efficient technology for coal-fired plants during heating seasons. Currently, wires transport electric from CHP to destination while urban pipes network transport heat from CHP to destination, respectively. However, this might not be the case in future, when eco-industrial parks are close to plants or pipes network can’t carry enough heat. This paper presents a feasible regional integrated energy system which meets both electric and heat’s needs with steam from CHP while maintaining photothermal resources’ high percent utilization. This system includes a coal-fired CHP plant, pressure matcher, steam supply pipeline, screw turbine and solar thermal utilization part. This paper set up a model of 600 MW electric power CHP with pressure matcher and screw turbine in Ebsilon software. Then the steam supply pipeline and solar thermal utilization part were developed and analyzed based on the basic thermodynamic theories with Beijing and Huzhou’s meteorological statistics taken into consideration. Besides, the operational issues of the regional system were also listed. Meanwhile, the regional integrated energy system was obtained and a lot of characteristics were analyzed. Main devices were further investigated with energy, exergy and entransy analysis. Three extreme working situations were also carried out and discussed in the end. Several useful conclusions were drawn. It’s necessary for China to masterly integrate regional energy system with multi-energy. Moreover, pressure matcher is high-efficient in general under other parameters’ influences. This extracting steam’s technology might be considered in future. Besides, low-stent placed pipeline which can transport high-parameter steam 4 km at most was introduced. A proper mass flow value or lower inlet temperature will both reduce loss of pipeline. Furthermore, heat user side can offer electric power about 9.22 MW, heating acreage about 0.79 km2 to the eco-industrial park. More solar heat’s import, lower upper temperature difference and less sunlight will favor solar thermal utilization part. Higher heat load or lower CHP’s working condition will benefit screw turbine. Peak heat exchanger doesn’t need to work when supply domestic water temperature’s demand is less than 65 °C. The simulation in this paper might give technological statistics to the regional integrated energy system which has CHP and photothermal. This will help to put this energy system into actual use in future.

Aiming at the large heat loss inside the traditional trough-type vacuum solar heat collecting tube, a new type of spiral three-blade rotor structure was designed and inserted into the inner tube side of the heat collecting tube. Based on the principle of fluid dynamics and field synergy, a mathematical model of the three governing equations of the fluid in the tube was established. Numerical simulations of the heat transfer and flow in the flow field in the two types of collector tubes with or without interpolated rotors were performed. Performance comparisons were made in terms of velocity field, pressure field, temperature field, and field synergy coupling ability. The results of the comprehensive evaluation index of heat transfer performance were finally given. The research shows that the PEC value continues to become larger with the increase in the inlet flow rate, from an initial value of 1.63 to a final value of 2.69. The heat transfer performance enhancement advantage of the new type vacuum heat collector tube is obviously greater than the disadvantage of flow resistance, and the comprehensive performance is better.

Fully hydraulic wind power generation is an emerging research direction. These hydraulic wind power generators replace the rigid connection between wind turbine and generator with a hydraulic flexible transmission system. This effectively absorbs a majority of the fluctuating load from the wind turbine, thereby achieving step less speed change and enabling the generator within the unit to maintain stable rotational speeds. The fully hydraulic wind power generator is different from the traditional wind power generators in terms of the transmission system used. As a result, the research here is focused on the transmission characteristics of the hydraulic system. Moreover, the transmission characteristics of the fully hydraulic wind turbine were compared to wind turbines with a mechanical transmission, from the analysis of the comparison different operating characteristics were revealed. The experiments using a test bench to study the full hydraulic wind power generator, whereas simulations using a model wer...