Quantifying the contribution of individual technologies in integrated urban energy systems – A system value approach

Abstract

Integrated urban energy systems satisfy energy demands in a cost-effective manner by efficiently combining diverse technologies and energy saving strategies. However, the contribution of an individual technology within a complex system is difficult to quantify. This study introduces a generalized "system value" approach to quantify the contribution of an individual design decision towards improving the system design (e.g., achieving a lower cost design). It measures the contribution of an individual technology to the whole system in the range between two benchmarks that respectively represent complete exclusion of the technology and the optimal penetration level. The method is based on a technology-rich Mixed Integer Linear Programming (MILP) model for optimal design of urban energy systems. The model considers multi-energy supply technologies, networks, storage technologies and various energy saving strategies. A stochastic formulation is further developed to quantify uncertainties of the system value. The system values of nine kinds of energy supply technologies and three categories of energy-saving strategies are quantified via a case study, which illustrates the variation in the system values for individual technologies with different levels of penetration, and multi-energy supply technologies can have a large impact in integrated systems.

Bi-Level Planning Model for Urban Energy Steady-State Optimal Configuration Based on Nonlinear Dynamics

“…Regarding the evaluation of the urban energy system, most scholars analyzed it from the aspects of reliability, sustainability, and stability. Rui J et al [15] introduced ecological network analysis (ENA) as a general system analysis tool to simulate and evaluate urban energy supply security. The evaluation contents included the overall realizability evaluation, system attribute analysis, and structure analysis of the energy supply system.…”

Unlocking emerging impacts of carbon tax on integrated energy systems through supply and demand co-optimization

“…The building envelope upgrading scheme acts as an energy-saving technology in the present study by varying the thermal properties of external walls, roofs, and windows. Compared with the uncertainties of other factors affecting the energy demands of buildings, envelope construction can be designed and determined at the planning stage, and its properties are fairly stable during the planning period [28].…”

“…Fig. 4 illustrates the proposed IES superstructure considering a series of energysupply technologies and demand-side envelope upgrading technologies to fulfill electricity, cooling, and heating demands simultaneously, modified from the previous study [28]. Moreover, the stochastic programming based co-optimization model, including various supply and demand-side scenarios, could cause high-dimensional problems with overlong solving time [35].…”

Combining state space demand modeling with design optimization for integrated energy systems planning

“…There are two main ways of thinking when existing research methods deal with the integrated energy system planning problem of supply and demand synergy. One is to start from the perspective of energy sector planning [4] [5], and the calculation and simulation of building energy consumption is relatively crude, without considering the factor of heat storage in the envelope structure changing with time, which leads to large errors in the building load results caused by this part and affects the actual operation effect of the system. Another way of thinking is that both demand-side load simulation and supply-side energy system simulation are done based on simulation tools [6].…”