BAK RESS are widely used in ordinary households, small business districts, offices, uninterruptible power supply fields, areas with peak-valley electricity price difference,etc. Mode 1.Spontaneous Self-use Scenario: Applicable to areas with low electricity subsidy and high electricity price. Advantage: Reduce grid electricity consumption, improve PV utilization rate, reduce electricity cost. Mode 2.Backup Power Supply Scenario: Applicable to the unstable power grid areas. Advantage: Solve problems of unstable power grid, difficult-to-use electricity, emergency electricity, and greatly improve the reliability and convenience of electricity. Mode 3.Peak-to-Valley Arbitrage Scenario: Suitable for areas with large peak & valley electricity price differences. Advantage: Charge when electricity price is low, discharge when electricity price is high, realize peak and valley arbitrage.