Global Solar Radiation Models in Minas Gerais, Southeastern Brazil

Table 3

Validation performance carried out for the models that presented the best fits for global solar radiation estimations in Minas Gerais (2011–2016).

Location	Models	Statistics
		RMSE (MJ·m^−2 day^−1)	MAPE (%)	d (dimensionless)	c-index (dimensionless)
Araçuaí	Nw	5.50	32.92	0.57	0.26 (extremely poor)
	AE	5.50	32.80	0.57	0.26 (extremely poor)
	JS	5.31	32.81	0.70	0.35 (extremely poor)
	Gd	5.32	33.04	0.57	0.26 (extremely poor)
	EY	5.51	32.99	0.57	0.26 (extremely poor)
Araxá	Nw	5.42	25.82	0.68	0.33 (extremely poor)
	AE	5.44	25.95	0.68	0.33 (extremely poor)
	JS	5.62	28.51	0.93	0.40 (extremely poor)
	Gd	5.57	27.84	0.62	0.26 (extremely poor)
	EY	5.44	25.94	0.68	0.33 (extremely poor)
Belo Horizonte	Nw	5.13	29.95	0.54	0.18 (extremely poor)
	AE	5.13	29.95	0.54	0.18 (extremely poor)
	JS	5.06	38.57	0.75	0.27 (extremely poor)
	Gd	4.98	30.00	0.40	0.13 (extremely poor)
	EY	5.14	29.96	0.54	0.18 (extremely poor)
Caratinga	Nw	5.96	42.18	0.54	0.25 (extremely poor)
	AE	5.97	42.24	0.54	0.25 (extremely poor)
	JS	6.03	48.93	0.59	0.27 (extremely poor)
	Gd	6.00	42.26	0.93	0.41 (very poor)
	EY	5.95	42.27	0.96	0.44 (very poor)
Lavras	Nw	2.78	15.18	0.93	0.83 (very good)
	AE	2.79	15.30	0.93	0.82 (very good)
	JS	3.43	32.56	0.89	0.72 (good)
	Gd	3.33	17.16	0.88	0.72 (good)
	EY	2.78	15.20	0.93	0.83 (very good)
Machado	Nw	3.49	17.85	0.90	0.76 (very good)
	AE	3.50	17.94	0.90	0.76 (very good)
	JS	4.37	32.58	0.82	0.62 (reasonable)
	Gd	4.35	23.10	0.82	0.61 (reasonable)
	EY	3.49	17.76	0.91	0.76 (very good)
Montes Claros	Nw	3.49	31.25	0.87	0.69 (good)
	AE	3.50	31.36	0.87	0.68 (good)
	JS	4.06	34.71	0.89	0.63 (reasonable)
	Gd	3.83	34.15	0.82	0.60 (poor)
	EY	3.46	30.80	0.87	0.69 (good)
Paracatu	Nw	3.56	15.82	0.88	0.71 (good)
	AE	3.56	15.89	0.88	0.71 (good)
	JS	3.98	21.42	0.84	0.64 (reasonable)
	Gd	3.93	18.67	0.84	0.64 (reasonable)
	EY	3.56	15.81	0.88	0.71 (good)
Pirapora	Nw	5.14	37.46	0.76	0.49 (very poor)
	AE	5.14	37.34	0.75	0.48 (very poor)
	JS	5.62	72.32	0.67	0.41 (very poor)
	Gd	5.23	38.44	0.72	0.44 (very poor)
	EY	5.14	37.37	0.76	0.49 (very poor)
Viçosa	Nw	3.34	21.73	0.90	0.78 (very good)
	AE	3.35	21.78	0.90	0.78 (very good)
	JS	3.76	39.87	0.87	0.72 (good)
	Gd	3.82	24.22	0.86	0.70 (good)
	EY	3.33	21.61	0.91	0.78 (very good)

Values in parentheses represent the performance classification by c-index, where c > 0.85 represents excellent performance, 0.76 < c < 0.85 represents very good performance, 0.66 < c < 0.75 represents good performance, 0.61 < c < 0.65 represents reasonable performance, 0.51 < c < 0.60 represents poor performance, 0.41 < c < 0.50 represents very poor performance, and c ≤ 0.40 represents extremely poor performance [58].