Techno-Economic Assessment of Wind Farm Repowering: A case Study of Zafarana Station, Gulf of Suez, Egypt

Abstract

The Zafarana wind farm was commissioned on phases since 2001 till 2010 with a total installed capacity of 545 MW.The development of the plant was not optimum, as some late phases was developed upstream of earlier one and the site utilization was not optimized as one plot. The wind farm is located at the Gulf of Suez, an area with abundant wind resource and strong infrastructure. Therefore, repowering scenario was favored over decommissioning or revamping as it enables to exploit and optimize the wind resource at the site and make use of the existing infrastructure of the old plant while using up-todate wind technology. A techno-economic assessment showed that the repowering of Zafarana, with new turbines that better match the site conditions and optimized micrositing, can increase the installed capacity from 545 MW to 750 MW. The repowering at the currently permissible tip height of 100 m is economically feasible, however this feasibility shall improve as height restriction is relaxed to 125 m. This will lead to improvement in the capacity factor and consequently annual energy production, such that the cost of generated energy will go down from 67.5 to 47.5 US$/ MWh calculated at IRR=14%. This cost takes into account the cost of early decommissioning of part of the plant, which has not expired yet. If the improvement in capacity credit due to the repowered project is considered, the feasibility of the repowering project shall improve such that the net cost per MWh will approach 40 US$/MWh (at IRR on equity of 14%).