Using Stressed Grids as a Storage Medium for Renewable Energy /

Abstract

In Pakistan, the people currently use solar power to charge the battery backup when the sun is available and use the stored power during the loadshedding events. This approach requires the use of battery backups that constitute more than 50% of the life cycle costs for solar systems due to high recurring costs. If the need of battery backups is somehow eliminated, it will not only relieve the people of significant economic burden, thus promoting solar power, as well as remove the inefficiencies associated with battery backups. In this thesis, we aim to develop a novel energy management system for solar PV systems in developing countries. We propose the use of highly stressed grids of these countries as a storage medium for solar PV systems where the consumers will use the solar power during non-loadshedding hours, instead of storing, which will be counted as their energy-credits. The consumers will be able to exchange these credits with direct power from the grid during loadshedding events. In this way, we eliminate the need of expensive battery backups and in turn promote renewable energy. We use Aashiyana as an energy management system that helps the consumer in better managing the available power from RE resources as well as the grid. Most importantly, Aashiyana has low cost overhead as its price corresponds to the one time cost of battery backups, while the provision of a user-friendly web interface enhances the consumers utility. We first present a novel algorithm to reward the solar power consumers based on the energy credit produced. We then show the fairness of our reward scheme as it ensures that the consumers are provided with atleast the amount of power that they would have received from the storage. We also demonstrate our ability to manage the power consumption of home according to the power threshold defined by the grid or the consumer during a particular hour. We believe the proposed idea to be equally beneficial for the grid operators as well as consumers. It saves consumers from the huge financial burden of recurring costs of battery backups. The push for the solar power coming from this approach will result in lesser demand supply gap, making the job of grid operator easier and reducing the need of huge fossil fuels based power plants.