Table 2.

The excess revenue that the retailer and each prosumer can make from the P2P market by participating in the spot market

Case	Total surplus (kWh)	Retail price (cents/kWh)	Spot price (cents/kWh)	Forecast to the prosumer (cents/kWh)	Trade in retail market	Trade in spot market	Total revenue from trading ($)	Revenue to the retailer ($)	Revenue to prosumer for proposed mechanism ($)	Revenue to prosumer for traditional P2P market ($)	Improvement of revenue per prosumer
1	15	7	800	800		√	120	60	12	0.21	57 times
2	15	7	800	400		√	120	60	12	0.21	57 times
3	15	7	800	6	√		1.05	0	0.21	0.21	Same performance
4	15	7	0	0	√		1.05	0	0.21	0.21	Same performance

The retail electricity selling price is assumed to be equal to 7 cents per kWh (Zahedi, 2010), and the spot price for case 1 and case 2 for the considered time slot is assumed to be 800 cents per kWh (the price is chosen from the spot price list of February 10, 2017, in Australian National Electricity Market (NEMWEB, 2020)). In case 2, we assume that there is a forecast error by the prosumers. However, because the forecasted price is more than the retail price, the prosumers still sell their excess to the spot market and gain revenue based on the actual market price. For deciding the retailer's benefit for facilitating this trading, in this example, it is assumed that the retailer kept 50% of the total revenue from the trading and then distribute the rest to the prosumers according to their contribution to the total traded energy. In case 3, although the spot market price is high, due to inaccurate forecast that is lower than the retail price, prosumers participate in the retail market. Although this detrimentally reduces their revenue compared with what they could achieve from the spot market, the excess revenue beyond P2P sharing to the prosumer is as same as the traditional P2P market. Case 4 demonstrates the same revenue as the traditional P2P market where prosumers sell their excess energy in the retail market after sharing in the P2P.