Abstract:

The penetration of distributed energy in the distribution network is increasing, which has caused great pressure to the power grid. The combination of energy storage and distributed generation system can reduce unstable electric energy into the network, reduce the impact of photovoltaic power on the power grid and improve the capacity to accept new energy. In view of the necessity of energy storage and the economic problems of projects, a comprehensive life cycle assessment model was established. This method studies the economy of the system from the aspects of project cost, annual income, total profit, static investment recovery period, and evaluates the social benefits of the project. The example shows that the utilization of power generation is high, the annual net income increases obviously, and its economy is less dependent on the electricity price and the degree of electricity subsidies. With the development of photovoltaic and energy storage, systems without energy storage will no longer have economic advantages, and the photovoltaic energy storage system has greater potential for development. Finally, combined with the experience in foreign countries, suggestions are put forward from the benefit feedback, electricity price incentives and financial support, so as to promote the healthy development of distributed photovoltaic industry.

Key words: distributed photovoltaic energy storage system, life-cycle, comprehensive benefit, storage cost, benefit feedback