  The transition to renewable energy systems causes increased decentralization
of the energy supply. Solar parks are built to increase renewable energy
penetration and to supply local communities that become increasingly
self-sufficient. These parks are generally installed in rural areas where
electricity grid distribution capacity is limited. This causes the produced
energy to create grid congestion. Temporary storage can be a solution. In
addition to batteries, which are most suitable for intraday storage, hydrogen
provides a long-term storage option and can be used to overcome seasonal
mismatches in supply and demand. In this paper, we examine the operational
decisions related to storing energy using hydrogen, and buying from or selling
to the grid considering grid capacity limitations. We model the problem as a
Markov decision process taking into account seasonal production and demand
patterns, uncertain solar energy generation, and local electricity prices. We
show that ignoring seasonal demand and production patterns is suboptimal. In
addition, we show that the introduction of a hydrogen storage facility for a
solar farm in rural areas may lead to positive profits, whereas this is
loss-making without storage facilities. In a sensitivity analysis, we show that
only if distribution capacity is too small, hydrogen storage does not lead to
profits and reduced congestion at the cable connection. When the distribution
capacity is constrained, a higher storage capacity leads to more buying-related
actions from the electricity grid to prevent future shortages and to exploit
price differences. This leads to more congestion at the connected cable and is
an important insight for policy-makers and net-operators.
