Network extension planning considering the uncertainty of feed-in from renewable energies

The integration of fluctuating renewable energy sources is a challenge for grids on all voltage levels. The feed-in of these energy sources is difficult to forecast and lies in certain limits of variation. Renewable energy plants are built at locations with a high potential e.g. high wind speeds that allow high utilization factors. However, grid constraints caused by the construction of energy plants are not considered for the choice of the location. The increasing amount of installed renewable energy plants causes the need for network reinforcements. For network planning, the grid operators have to anticipate the highest possible electricity feed-in. But this scenario only happens very rarely when several types of fluctuating generation, such as wind and photovoltaic, are installed. This paper presents a new approach for determining scenarios for an efficient network planning process which depends on the allowed feed-in from renewable energies. The reduction of the injected power and energy of renewable energies in relation to a reduction of network extension costs is discussed.