The electricity production system of New Zealand consists of 1000MW hydropower, 1500MW coal fired electricity and 2000MW natural gas capacity. All year round the electricity demand is 4000MW during daytime (7.00-23.00) and 2000MW during nighttime (23.00-7.00). The efficiency of coal-fired plants is 40% and the efficiency of natural-gas fired plants is 50%.
a) Calculate and draw the way the power sources are dispatched to achieve the lowest possible costs.
b) Calculate the average load factor of the natural gas-fired plants.
1000MW of off-shore wind energy (load factor 40%) is added to the electricity grid. The wind power production fluctuates, but on average is evenly spread over the day. The annual fixed cost of this wind energy is €200/kW – installed.
c) Again, calculate and draw the way the power sources are dispatched to achieve the lowest possible costs. Hint: place close attention to the load factors in the table above.
d) Calculate the average cost of this wind energy in €/kWh
e) Calculate the fuel savings achieved through the application of the wind energy.