基于供需互配的多能互补建筑能源系统优化集成机制研究

With the continuous depletion of fossil fuels, the building energy system is gradually changing from a single form of conventional energy to a multi-energy system that includes multiple renewable energy sources. A multi-energy complementary system has numerous variables and the reliability and controllability of renewable energy are usually not as good as that of conventional energies. Therefore, the design and operation of multi-energy systems based on renewable energy are extremely complex and worthy of further study..In order to emphasize the energy imbalance issue and the low utilization efficiency of renewable energies, which are commonly encountered in real applications, this project proposes to establish the coupling mechanism of multi-energy complementarity optimization based on co-adaptive matchmaking between supply and demand. First of all, a unified mathematical model of a multi-energy system will be the established, in which the core idea is to use a matrix approach to standardize the unified modeling of a variety of building energy processes including energy generation, energy utilization and energy storage. Secondly, the matrix model is used to simultaneously optimize the key characteristics of supply and demand side such as the grade, quantity, time of energy, until the best energy balances between supply and demand are achieved. The required energy storage system is then constructed according to the unbalance residual. Finally, the optimal integration scheme for multi-energy complementary systems is determined from the point of view of the total energy consumption in the whole life cycle. Through the comprehensive optimization of the building energy structure, the contribution rate of renewable energy and the overall efficiency of the whole energy system can be greatly enhanced.

建筑能源系统逐渐由常规能源为主的单一形式向包含多种可再生能源的多能互补模式转变。多能互补系统特性迥异、变量繁多，因此可再生能源多能互补耦合系统值得深入研究。本项目针对建筑能源结构不合理导致供需不平衡、能源效率低等问题，研究基于供需互配的建筑多能互补系统优化集成机理。首先，建立多能源系统统一数学模型，其核心思想是采用矩阵方式对各种建筑能源的产能、用能、蓄能等过程进行标准化统一建模；其次，建立“供需互配”建筑能源结构优化机制，供需双方根据供需匹配结果对设计方案进行自适应调整和交替优化，直至为每种供能方案匹配到最合适的用能／蓄能方案，从根源上减少供需错配；最后，以建筑全生命周期总能耗最小为优化目标，从所有满足供需匹配的初选方案中遴选整体能效最佳的多能互补集成方案。通过对建筑能源结构的全面优化，本项目可有效减少供需错配、提升可再生能源和系统整体的利用效率，为多能互补系统应用和推广提供理论支撑。

建筑多能互补系统协调多种能源运行，可发挥不同系统的优势和潜力，促进可再生能源利用。同时，由于可再生能源具有随机、间歇等特点，其供能品质及可控性远不如常规能源，对建筑多能互补能源系统的建模、设计及运行等方面提出了更高的要求。针对基于可再生能源多能互补的建筑能源系统在系统建模和设计优化方面存在突出问题，本项目提出基于Energy-Hub的多能互补系统建模方法和基于供需互配的建筑能源系统优化设计方法，并将其在北京奥运村“微能耗建筑”示范项目进行实际应用和效果验证。主要研究工作如下：（1）提出基于Energy-Hub的多能互补系统建模方法，采用矩阵方式对各种建筑能源系统中的能量流动和转换关系进行标准化统一建模。同时，将整个多能互补系统拆分为产能系统、用能系统和蓄能系统，并分别建立各自的能源枢纽模型，通过能量和功率平衡建立各系统间的耦合关系。（2）针对目前多能互补建筑能源系统设计过程中，未将需求侧纳入能源优化匹配过程从而造成能源结构不合理、能源供需不匹配等突出问题，提出了基于“供需互配”思想的优化设计方法，并给出该优化方法在多能互补建筑能源系统中的具体实施步骤。“供需互配”优化机制的核心内涵是指在建筑能源系统设计流程中，供需双方基于能源供需匹配结果进行自适应调整和交替优化，从而实现供需双方在能源种类、品位、大小和时间等多个维度上的最大化撮合，从能源结构这一根源上减少能源的供需错配，实现最佳匹配。（3）采用全生命周期分析方法，将包括投资成本和运行成本在内的全生命周期总成本作为确定建筑能源系统最佳设计方案的目标函数。（4）以北京奥运村“微能耗建筑”示范项目为研究对象，对所提出的Energy-Hub建模方法和“供需互配”优化设计方法进行验证。应用结果表明该系统能够实现全生命周期总成本降低7.4%，年总用电量节约40.1%，年二氧化碳排放可减排11.9%。本项目可有效减少建筑能源供需错配、提升可再生能源和系统整体的利用效率，为建筑实现节能低碳目标提供理论支撑。