Previous studies have identified links between the urban form and the performance of urban energy systems. Land use and density are two important aspects of urban planning and design. This paper studies the relationship between these aspects and the performance of an urban energy system. For this, the study compares different metrics of land use, density, and energy performance. These metrics are floor area ratio, density gradient, land use ratio, renewable energy share, and the peak electricity import from the city grid. The approach is based on the multi-objective optimization of the urban form. The results offer what-if scenarios on how land-use and density can either maximize the performance of an urban energy system.