Uncertainty-Based Capacity Factors of Operational Wind Turbines Using the Generalized Likelihood Uncertainty Estimation (GLUE) Method

Table 1

The monthly estimated capacity factors based on Chang et al. [3] and measured capacity factors for wind turbine #1 between 2002 and 2011. The error is calculated as |measured-estimated|/measured.

Scenario	Variable	Year
		2002	2003	2004	2005	2006	2007	2008	2009	2010	2011
January	Estimated	0.582	0.766	0.839	0.749	0.785	0.927	0.763	0.790	0.606	0.965
	Measured	0.621	0.752	0.822	0.743	0.809	0.941	0.802	0.773	0.661	0.983
	Error (%)	6.3%	1.9%	2.1%	0.8%	3.0%	1.5%	4.9%	2.2%	8.3%	1.8%
February	Estimated	0.595	0.526	0.567	0.627	0.680	0.492	0.915	0.462	0.464	0.630
	Measured	0.596	0.533	0.567	0.509	0.730	0.512	0.871	0.424	0.479	0.663
	Error (%)	0.2%	1.3%	0.0%	23.2%	6.8%	3.9%	5.1%	9.0%	3.1%	5.0%
March	Estimated	0.397	0.526	0.610	0.501	0.510	0.468	0.467	0.498	0.419	0.696
	Measured	0.396	0.542	0.661	0.202	0.527	0.454	0.453	0.530	0.449	0.743
	Error (%)	0.3%	3.0%	7.7%	148.0%	3.2%	3.1%	3.1%	6.0%	6.7%	6.3%
April	Estimated	0.368	0.362	0.360	0.283	0.347	0.420	0.363	0.472	0.438	0.313
	Measured	0.383	0.310	0.356	0.220	0.323	0.500	0.378	0.490	0.426	0.301
	Error (%)	3.9%	16.8%	1.1%	28.6%	7.4%	16.0%	4.0%	3.7%	2.8%	4.0%
May	Estimated	0.193	0.359	0.231	0.268	0.373	0.099	0.372	0.262	0.211	0.267
	Measured	0.184	0.345	0.217	0.206	0.315	0.099	0.323	0.298	0.229	0.222
	Error (%)	4.9%	4.1%	6.5%	30.1%	18.4%	0.0%	15.2%	12.1%	7.9%	20.3%
June	Estimated	0.154	0.357	0.350	0.238	0.148	0.115	0.138	0.217	0.356	0.160
	Measured	0.145	0.319	0.145	0.221	0.139	0.129	0.134	0.186	0.266	0.178
	Error (%)	6.2%	11.9%	141.4%	7.7%	6.5%	10.9%	3.0%	16.7%	33.8%	10.1%
July	Estimated	0.209	0.129	0.234	0.280	0.347	0.085	0.282	0.112	0.104	0.097
	Measured	0.196	0.117	0.204	0.176	0.258	0.091	0.228	0.114	0.115	0.119
	Error (%)	6.6%	10.3%	14.7%	59.1%	34.5%	6.6%	23.7%	1.8%	9.6%	18.5%
August	Estimated	0.154	0.132	0.210	0.189	0.122	0.274	0.064	0.236	0.051	0.176
	Measured	0.135	0.122	0.113	0.151	0.067	0.259	0.066	0.215	0.060	0.172
	Error (%)	14.1%	8.2%	85.8%	25.2%	82.1%	5.8%	3.0%	9.8%	15.0%	2.3%
September	Estimated	0.433	0.347	0.313	0.358	0.534	0.344	0.278	0.310	0.305	0.348
	Measured	0.384	0.347	0.337	0.277	0.390	0.354	0.309	0.331	0.298	0.369
	Error (%)	12.8%	0.0%	7.1%	29.2%	36.9%	2.8%	10.0%	6.3%	2.3%	5.7%
October	Estimated	0.556	0.670	0.927	0.792	0.737	0.765	0.571	0.759	0.697	0.791
	Measured	0.435	0.696	0.945	0.763	0.578	0.846	0.605	0.782	0.737	0.782
	Error (%)	27.8%	3.7%	1.9%	3.8%	27.5%	9.6%	5.6%	2.9%	5.4%	1.2%
November	Estimated	0.740	0.766	0.688	0.530	0.569	0.895	0.641	0.631	0.818	0.658
	Measured	0.709	0.779	0.725	0.597	0.545	0.913	0.380	0.703	0.820	0.706
	Error (%)	4.4%	1.7%	5.1%	11.2%	4.4%	2.0%	68.7%	10.2%	0.2%	6.8%
December	Estimated	0.750	0.820	0.886	0.876	0.887	0.710	0.735	0.727	0.623	0.919
	Measured	0.707	0.806	0.890	0.898	0.910	0.701	0.680	0.675	0.330	0.902
	Error (%)	6.1%	1.7%	0.4%	2.4%	2.5%	1.3%	8.1%	7.7%	88.8%	1.9%
Strong-wind	Estimated	0.596	0.672	0.747	0.672	0.687	0.693	0.667	0.636	0.590	0.777
	Measured	0.576	0.686	0.771	0.621	0.683	0.730	0.631	0.651	0.580	0.799
	Error (%)	3.5%	2.0%	3.1%	8.2%	0.6%	5.1%	5.7%	2.3%	1.7%	2.8%
Weak-wind	Estimated	0.261	0.296	0.289	0.279	0.318	0.250	0.278	0.282	0.262	0.242
	Measured	0.237	0.259	0.228	0.208	0.248	0.237	0.239	0.271	0.231	0.226
	Error (%)	10.1%	14.3%	26.8%	34.1%	28.2%	5.5%	16.3%	4.1%	13.4%	7.1%
One-year	Estimated	0.436	0.484	0.501	0.480	0.491	0.463	0.453	0.453	0.431	0.487
	Measured	0.406	0.472	0.499	0.414	0.465	0.483	0.435	0.461	0.405	0.512
	Error (%)	7.4%	2.5%	0.4%	15.9%	5.6%	4.1%	4.1%	1.7%	6.4%	4.9%