  A multiple market trading mechanism for the VPP to participate in
electricity, renewable energy certificate (REC) and carbon emission right (CER)
markets is proposed. With the introduction of the inventory mechanism of REC
and CER, the profit of the VPP increases and better trading decisions with
multiple markets are made under the requirements of renewable portfolio
standard (RPS) and carbon emission (CE) quota requirements. According to the
Karush-Kuhn-Tucker (KKT) conditions of the proposed model, properties of the
multiple market trading mechanism are discussed. Results from case studies
verify the effectiveness of the proposed model.
