  This paper proposes a cloud energy storage (CES) model for enabling local
renewable integration of building consumers (BCs). Different from most existing
third-party based ES sharing models that the energy storage operator (ESO)
gains profit by leasing energy or power capacity, our CES model allows the ESO
to sell renewable utilization service (RUS) to its consumers, i.e., the total
amount of local renewable generation shifted to supply their demand. Notably,
we propose a quadratic price model for the ESO charging its consumers by their
requested RUS and formulate their interactions as a Stackelberg game, which
admits an equilibrium. We prove the CES model outperforms individual ES (IES)
model in social welfare. Besides, we study the performance of the CES model
compared with the IES model and an existing ES sharing model (referring to VES
model) via case studies. We demonstrate the CES model can provide 2-4 times
profit to the ESO than the VES model. Meanwhile, higher cost reduction for the
BCs are secured by the CES model. Moreover, we show the CES model can achieve
near social optima and high ES efficiency (i.e., utilization) which are not
provided by the other ES models.
