Ecodesign of Ever Net-Load Microgrids

The European Union has promoted the process of electrical market liberalization, extended to residential/commercial buildings, and a strong encouragement toward the rational use of energy. The European energetic policy aims to promote the installation of small renewable power sources, the use of highly efficient cogeneration, and the Nearly Zero-Energy Buildings (NZEBs) that have to be pursued as much as possible by local generation sufficient to supply the residual amount of energy. To avoid future chaotic phenomena in the existing distribution network, this paper highlights that the power flow of local generators has to be maintained locally: The users have to remain net-loads organized in ever net-load microgrids at least in a first evolution. The actual distribution network for low-voltage customers appears inadequate to comply with these improvements, and it has to change in order to accept microgrids organized by the union of customer groups. The authors suggest the ecodesign of the microgrids able to constitute the NZEB and to accomplish the goals of enhanced safety, high local power quality, dc distribution systems, common emergency systems, efficient load shedding, and energy management. The microgrids guarantee a reduced impact as ever net-load on the net supply.