Environmental and economic optimization of office building microgrid based on carbon-electricity market and improved Harris Hawks optimization algorithm

To improve access to renewable energy and promote economic development, office buildings require microgrids. Meanwhile, with the implementation of China's "dual-carbon" targets and the unified carbon market, how small and medium-sized renewable energy generation units, represented by office building microgrids, can participate in the carbon-electricity market and obtain economic benefits through it is a question that must be considered in the future. Therefore, this paper first establishes a carbon-electricity market model incorporating small and medium-sized renewable energy producers such as office building microgrids, and simulates the changes in carbon prices and electricity prices after their integration into the carbon-electricity market. Secondly, aiming to minimize total economic costs, an economic optimization model for office building microgrids based on the carbon-electricity market is constructed, and an improved Harris Hawks Optimization (HHO) algorithm is employed to solve it. The research results indicate that, on the one hand, this model effectively promotes the development of China's carbon market by advancing the timing of the carbon price peak by 10 % and extending its duration by 50 %, thereby accelerating the transformation of the social energy structure. On the other hand, office building microgrids operating based on the carbon-electricity market and utilizing economic optimization effectively reduce economic costs, with economic benefits increasing by 43.4 % in typical months of spring and autumn, and economic costs decreasing by 19.1 % in typical months of winter and summer. Additionally, the loss of energy storage equipment is significantly reduced, which not only promotes the development of renewable energy and protects the environment but also enhances economic growth and facilitates the better development of enterprises.