In the past, we have observed several large blackouts, i.e. loss of power to large areas. It has been noted by several researchers that these large blackouts are a result of a cascade of failures of various components. As a power grid is made up of several thousands or even millions of components (relays, breakers, transformers, etc.), it is quite plausible that a few of these components do not perform their function as desired. Their failure/misbehavior puts additional burden on the working components causing them to misbehave, and thus leading to a cascade of failures. The complexity of the entire power grid makes it difficult to model each and every individual component and e stability of the entire system. For this reason, it is often the case that abstract models of the working of the power grid are constructed and then analyzed. These models need to be computationally tractable while serving as a reasonable model for the entire system. In this work, we construct one such model f...