  This is a second part of the research on AC optimal power flow being used in
the lower level of the bilevel strategic bidding or investment models. As an
example of a suitable upper-level problem, we observe a strategic bidding of
energy storage and propose a novel formulation based on the smoothing
technique. After presenting the idea and scope of our work, as well as the
model itself and the solution algorithm in the companion paper (Part I), this
paper presents a number of existing solution techniques and the proposed one
based on smoothing the complementary conditions. The superiority of the
proposed algorithm and smoothing techniques is demonstrated in terms of
accuracy and computational tractability over multiple transmission networks of
different sizes and different OPF models. The results indicate that the
proposed approach outperforms all other options in both metrics by a
significant margin. This is especially noticeable in the metric of accuracy
where out of total 422 optimizations over 9 meshed networks the greatest AC OPF
error is 0.023% that is further reduced to 3.3e-4% in the second iteration of
our algorithm.
