oemof / oemof-solph

                    )

        for n in self.INVESTSTORAGES:

            if valid_sequence(n.storage_costs, len(m.TIMESTEPS)):

                # We actually want to iterate over all TIMEPOINTS except the

                # 0th. As integers are used for the index, this is equicalent

                # to iterating over the TIMESTEPS with one offset.

                if not m.TSAM_MODE:

                    for t in m.TIMESTEPS:

                        storage_costs += (

                            self.storage_content[n, t + 1] * n.storage_costs[t]

                        )

                else:

                    for t in m.TIMESTEPS_ORIGINAL:

                        storage_costs += (

                            self.storage_content[n, t + 1]

                            * n.storage_costs[t + 1]

                        )

        self.storage_costs = Expression(expr=storage_costs)

        storage_costs = 0

        for n in self.STORAGES:

            if valid_sequence(n.storage_costs, len(m.TIMESTEPS)):

                # We actually want to iterate over all TIMEPOINTS except the

                # 0th. As integers are used for the index, this is equicalent

                # to iterating over the TIMESTEPS with one offset.

                if not m.TSAM_MODE:

                    for t in m.TIMESTEPS:

                        storage_costs += (

                            self.storage_content[n, t + 1] * n.storage_costs[t]

                        )

                else:

                    for t in m.TIMESTEPS_ORIGINAL:

                        storage_costs += (

                            self.storage_content[n, t + 1]

                            * n.storage_costs[t + 1]

                        )

        self.storage_costs = Expression(expr=storage_costs)