Evaluation of photovoltaic technologies with electrochemical energy storage for residential usage and economic considerations

In today’s modern world, energy is a key factor affecting our daily lives, as our dependency on energy and energy consumption levels increase with the progression of technology, maybe the most important challenge to overcome for having a sustainable future where fossil fuels will one day inevitably deplete, is the widespread adoption of renewable energy systems. Solar power is one of the most promising renewable energy technologies due to the abundancy of the primary energy source and widespread availability of it all over the world. If utilized properly, solar irradiation can deliver an amount of energy that is many orders of magnitude larger than the energy that the world needs. This thesis explores the characteristics of solar power and fundamentals of different solar PV technologies and recent developments in the field including state of the art technology. The industry is still dominated by the crystalline silicon technologies but thin films which are cheaper and utilize less material are also alternatives as well as emerging promising technologies such as perovskite solar cells which have already showed remarkable efficiency levels in such a short period of research. The main focus of the thesis is on the residential PV systems where in recent years due to increased production scales and developments, the solar PV systems got much cheaper for the average consumer. In many countries grid-parity has been achieved for photovoltaics with levelized cost of electricity (LCOE) lower than the actual grid retail price. This, combined with the trend of decreasing feed-in-tariffs renders self-consumption a very viable option. Thus, energy storage systems with a focus on electrochemical storage for residential use, are analyzed with their pros and cons, their characteristics and suitability for residential systems with comparison to each other, the trends that are driving the battery industry forward and other details have been discussed. The most suitable storage systems for residential usage are the lead-acid battery and the Lithium-ion battery. In recent years, with the developments in electric car industry and increased production scales from companies such as Tesla have caused a significant drop in the pricing of Li-ion and this trend is expected to continue which may make them more widely available also for residential usage in the near future. With the price drops, the technical characteristics of Li-ion batteries can make up for the high upfront costs compared to lead-acid in the long run and they may even end up cheaper. Finally, economic considerations regarding PV system with storage, their pricing and future trends, most important incentive mechanisms, calculation methods for evaluating whether a system would be profitable or not, the effects of high residential PV penetration on the distribution network, the impact of energy storage and load management on the daily energy load curve, main parameters to consider while sizing the PV system and other details have been discussed.