A novel payment scheme for trading renewable energy in smart grid

With the increasing diffusion of renewable energy producers in electricity grids, new policies and tariff systems have been recently developed. This work revolves around a particular support system named NRG-X-Change, which makes use of a virtual currency called NRGcoin. The NRG-X-Change system is based on two NRGcoin payment functions: one to establish the price at which prosumers are rewarded for their energy production, and the other to establish the price at which consumers pay the energy they consume. The detailed analysis provided in this paper identifies some important issues in these payment functions limiting their applicability, namely: (i) not taking congestions into account; (ii) encouraging curtailment of renewable energy production; and (iii) not ensuring that the prosumers consume their own energy before selling it. This work addresses these limitations by proposing two novel payment functions whose advantageous properties are demonstrated by theoretical analysis and in simulation using real data coming from an existing grid.