Distributed photovoltaics with peer-to-peer electricity trading

Abstract

Distributed electricity generation technologies, like solar photovoltaic (PV), have achieved rapid development in recent years, but are constrained by some problems such as low marketization and lag in public services. The peer-to-peer (P2P) electricity trading, which allows direct electricity transactions between local consumers and prosumers, has the potential to efficiently distribute the profits coming from self-consumption of PV electricity among all participants. This study proposes a three-layer P2P electricity trading system for communities with high penetration of household distributed PV. The trading system includes a physical layer based on the power grid, an information layer based on a virtual agent network, and a market layer based on a continuous double auction (CDA) mechanism combined with market clearing. By using simulation of trading experiments, a community with 60 houses and 50% PV occupancy is studied as a case. Results show that in one day, 62.5% of the surplus PV electricity of all prosumers actually can be consumed within the community. Through P2P electricity trading of this part of electricity, total incomes of prosumers can increase by 11.5%, and total expense of all users decrease by 7.5%, resulting in that the net expenses of the whole community decrease by 13.8%. It is concluded that P2P electricity trading can unite the whole PV community as a bigger prosumer, and make every residential house in the community share the profits from local PV consumption, which could promote the subsidy-free development and grid parity of household distributed PV in the future.