Evaluation of combined heat and power plants with electricity regulation

The contribution of thermal power will change to the peak-shaving power supply in the future power supply structure. Most combined heat and power plants in northern China are mainly used as heat sources for central heating systems. To improve the electricity regulation ability and evaluate objectively, this study establishes an evaluation method of cogeneration peak shaving which reflects the marginal cost of power generation in the valley and the peak period. It is the relationship between the revenue per kW of the deep peak shaving capacity during the valley period and the utilization hours of peak-shaving equipment. The characteristics and applica-bility of four peak shaving methods are analyzed. Electric boiler method and direct steam extraction method both have low investment and low heating income. However, the peak shaving depth of direct steam extraction method is limited. Absorption heat pump waste heat recovery method (AHPR) method and electric heat pump waste heat recovery method (EHPR) method both have high investment and high heating income. AHPR method has the limited peak shaving depth. By comparison, the peak shaving depth of EHPR method is less limited. This evaluation method provides the foundation for the configuration of the cogeneration power peak shaving system.

Automated summary

The contribution of thermal power will change to peak-shaving power supply in the future. Combined heat and power plants in northern China are mainly used for central heating. This study establishes an evaluation method for cogeneration peak shaving based on the marginal cost of power generation during peak and valley periods. Four peak shaving methods are analyzed for their characteristics and applicability. The evaluation method provides a foundation for configuring cogeneration power peak shaving systems.