1. Table 5: Monthly cluster variability numeric results;Figure
2. Advancement of energy storage devices and applications in electrical power system;S C Smith;2008 IEEE Power and Energy Society General Meeting-Conversion and Delivery of Electrical Energy in the 21st Century,2008
3. Long-term spatial and temporal solar resource variability over america using the nsrdb version;A Habte;Renewable and Sustainable Energy Reviews,1998