Poster: What Exactly Are We Assessing with 12x24s?
10 Sep 19
5:00 PM
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6:00 PM
Tracks:
Time Series Energy Modeling
The 12x24 production matrix is an important product developed in a wind resource assessment used to more accurately model the commercial efficiency of potential offtake agreements. 12x24s can also be used to better understand the meteorological conditions as measured on-site; for instance, a site-manager can plan extended maintenance activities for months when the wind is weaker. The question of whether to present a 12x24 based on solely the measured meteorological conditions measured on-site or to model what the POI will see as accurately as possible naturally arises due to the subtle differences between these two 12x24 approaches. With a greater emphasis on time-varying AEP and losses in recent years, inclusion of losses in a 12x24 is used to varying degrees. Some IEs present only the meteorological 12x24 while others include some time-varying losses. Certainly, not all losses can be characterized in the time domain, such as turbine availability, grid availability, grid curtailment, and performance degradation. Other losses, such as temperature shutdown, bat curtailment, and icing can easily be included. This poster examines the nuances between presenting a 12x24 based on simply the measured meteorological conditions on-site or the full expected output at the POI with the inclusion of time-varying losses. A direct comparison between the two formats will be shown to point out the small differences, as well as several “12x24s” of time-varying losses.