As the proportion of total Generation by Renewable sources compared to non-Renewable sources increases, the relative inertial stability provided by large rotating generators in electricity grids is found to shrink and is not being replaced by sources such as photovoltaic and wind power, which are already known for their inherent variability. This leads to electricity Generation systems being less stable, less flexible, and less adequate in applications with a high diversity factor, and literature shows that the penetration of Renewable energy sources in distribution-Generation/microgrid system frequently presents several technical and economic challenges in their usual applications. This work examines how increased Renewable energy penetration impacts the distribution-Generation system and suggests approaches and measures for tackling the challenges that are associated with it.

The progression towards smart grids, integrating Renewable energy resources, has increased the integration of Distributed generators (DGs) into power distribution networks. However, several economic and technical challenges can result from the unsuitable incorporation of DGs in existing distribution networks. Therefore, optimal placement and sizing of DGs are of paramount importance to improve the performance of distribution systems in terms of power loss reduction, voltage profile, and voltage stability enhancement. This paper proposes a methodology based on Dragonfly Optimization Algorithm (DA) for optimal allocation and sizing of DG units in distribution networks to minimize power losses considering variations of load demand profile. Load variations are represented as lower and upper bounds around base levels. Efficiency of the proposed method is demonstrated on IEEE 33-bus and IEEE 69-bus radial distribution test networks. The results show the performance of this method over other existing methods in the literature.

Lighting passages is done for citizens’ welfare simultaneously with the peak of the consumption of the network, from sunset to sunrise. The present study aimed at designing a model of sustainable urban management in the field of lighting, with simulation of the use of photovoltaic LEDs instead of sodium and halogen lamps. Accordingly, in a system simulation of the network, the scenarios for adjusting the input of various photovoltaic capacities to the electricity supply system of the city of Mashhad have been investigated. The results of on-grid analysis by using this decentralized production pattern shows, taking into account the 200 watts capacity and the 20% utilization factor for each photovoltaic LEDs and installing a photovoltaic LED instead of sodium and halogen lamps, all the power needed to lighting of city streets is provided by photovoltaic solar technology. Moreover, by reducing the potential between fossil and Renewable production, emissions of pollutants are reduced by 104, 000 tons. Therefore, this method can be used to manage clean and sustainable energy in urban scale consumption, and, while helping the environment and reducing air pollution, it prevents losses caused by the transfer of electrical energy from the plant to the place of consumption.