Args:
            comp (Composition): Input composition

        Returns:
            Energy of lowest energy equilibrium at desired composition. Not
            normalized by atoms, i.e. E(Li4O2) = 2 * E(Li2O)

def get_hull_energy(self, comp):
        """
        Args:
            comp (Composition): Input composition

        Returns:
            Energy of lowest energy equilibrium at desired composition. Not
            normalized by atoms, i.e. E(Li4O2) = 2 * E(Li2O)
        """
        e = 0
        for k, v in self.get_decomposition(comp).items():
            e += k.energy_per_atom * v
        return e * comp.num_atoms