Renewables diffusion and contagion effect in the Italian regional electricity markets: assessment and policy implications

In the electricity market, sudden price jumps occur more frequently than in other markets due to the peculiarity of electricity. Furthermore, the structural spot characteristics of the electricity market determine high price variability. All these characteristics have been accentuated by the dramatic increase of renewable energy supply in Italy starting in 2010. These features suggest the possibility of contagion effects across Italian regional electricity markets, considering contagion such as a sudden and significant increase in cross-market links arising from a shock to a specific market. In this paper we investigate whether such a renewable energy increase has affected the contagion behavior in the Italian electricity spot market taking into account both the difference between interdependence and contagion and the direction of the shock. We find empirical evidence, with significant tests, that no changes have occurred in interdependence mechanism, nor in contagion effects due to renewable energy sources development in Italy.