Scenario: An Aluminium manufacturing company in Sweden has two plants. The plant-1 received Bauxite (aluminium ore) as raw material and converts it to aluminium oxide. The plant-2 received aluminium oxide and produces aluminium ingots as output. Bauxite is transported by trucks to plant-1 and during the months around winter the transportation lead time triples due to icy road conditions. During the winter season due to adverse condition mining bauxite is almost not possible for 4 months. The end customers who buy the aluminium ingots from plant 2, buys the ingots in a steady manner to support their component production. Aluminium smelting which happens in plant-2 is highly power intensive and it is supported by one hydro-electric power plant and two thermal power plants. Two a great extent there is no power disruption. Both plant-1 and plant-2 are running at full capacities and plant-1 just meets the requirements of plant-2.