Optimization of Off-Shore Wind Power Plants Collection Grids

Paper in proceeding, 2013

This paper is based on the optimization of the total life time cost for the collection grids for an off-shore wind power plants. It is obvious that more power production, and thereby more revenues, can be expected with a high degree of redundancy. Even though full redundancy is theoretically possible, the upper economical viable limit has shown to be lower. Adding more reliability increases the investment costs, whereas the benefits are not increasing correspondingly. The optimization is demonstrated for a wind power plant layout with 8 wind turbines of 6 MW. Different scenarios are considered, from a radial layout up to a full redundancy solution. The different scenarios are based on standardized cable types and compared in relation to total life time cost. The total life time cost is based on capital costs, operational costs and production losses due to cable failures. The impacts of different average wind speeds, electricity prices, failure rates and mean repair times are investigated, presented and discussed. Finally a comparison between the layouts is done, which results in a minimum of costs at a redundancy around 70-75% for a wind power plant with typical conditions for the North Sea.