The role of district heating in the Chinese energy system

The purpose of this project was to analysis the significant energy saving contributed by development of district in the future. This work investigated the technical and economic potential of applying Danish experience with district heating in China especially for the renewable energy integration into district system combined with electricity sector. The objective of this research was to evaluate the relevant energy outcomes in terms of emission reduction, energy mix, technology mix of district heating in Chinese energy system. In the project we introduced a capacity expansion model to find the optimal energy mix of generation capacity in the Chinese power sector and district sector.

The calculations were divided into two tasks:

1. Mapping of heat demand, heat production and heat resource among provinces

This task focused on detailed investigation on heated building area, climate condition in heating period and energy requirement, which were used to make prediction of heat demand among different provinces. Due to the lack of statistical data of heat production capacity in China, accumulated capacity of CHP were separated from coal-fired power capacity. Evaluation of heat rate for CHP was also needed to describe the energy efficiency of existing heat production. Moreover, technical and economic potential of heat resource like industrial surplus heat, waste energy as well as renewable energy resource will be calculated and estimated.

2. Optimization of technology mix for heat sector

Because of large CHP installation in China, the technology mix in the heat sector was evaluated under the combined perspective with electricity system. Electricity system has a number of technical constraints that should be simulated rigorously in detailed power system model.

For conventional technologies, the representation of system model included heat rate, maximized output, must-run generation, etc. For CHP plants, cb-value and cv-value it was considered to describe the adjustment of heat output and power output. For renewable energy, these factors included the minimum and maximum output constrains due to variation of intermittent resource like wind, solar and water. In order to clarify the role of district heating in the future national energy system, optimization model of power system and heat system was developed to find the investment of different district heat options such as individual heat, CHP and renewable energy is needed to represent the competition between different technologies.

The model was used to analyze scenarios of various demand levels of district heating environmental policies as well as different prediction on economic and technical factors of technologies. In this model, the expansion of power production and heat production was generated endogenously, with the multi-regional and multi-period structure to represent the daily and seasonal variation of demand and resource.

The database for the Chinese heat sector has been build and  the results were included in the optimization model developed for this project and Energyplan.

Funded by

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