A Comparative Analysis of Pricing Mechanisms to Enable P2P Energy Sharing of Rooftop Solar Energy

Increasing environmental concerns have driven the adoption of clean energy sources at the local power system level. However, it is also the cost-economics that has led to the rise in bulk-power system-level participation of renewable energy sources like solar photovoltaic (PV). Distributed and decentralized energy systems have also emerged as an effective alternative to the centralized power system and many countries have announced target-driven policies to encourage the same. Rooftop solar PV is a popular form of distributed generation that has huge potential in facilitating local demand-supply balance and ensuring energy security. However, the true value of rooftop solar energy is not well discovered and enjoyed by both the consumers and the utilities and hence the rooftop solar PV penetration level has not risen significantly, particularly in India, which has an ambitious target of 40 GWp to be achieved by 2022. One of the possible ways to attract more consumer and utility interest in rooftop solar is to provide a fair degree of autonomy wherein the prosumers can sell their excess to their neighbors at prices determined competitively. Peer to peer (P2P) Energy Sharing is one such way of encouraging the same. However, efficient pricing mechanisms are required to enable such a framework along with effective and trust-based platforms to facilitate and manage the trading process. This paper discusses three of such pricing mechanisms - Mid-market rate, bill-sharing, and demand-supply ratio and benchmarks their performances against coalition game-theory based method which is best suited to model such a scenario. These have been compared on various performance indices for an institutional setup in India.