The industrial designs of the GoodWe ES series hybrid inverters, derive from technology demanded by German standards. The GoodWe ES series bi-directional hybrid inverter is applicable to both on-grid and off-grid PV systems. The GoodWe hybrid inverter includes twin MPP trackers to maximise the energy yield from two independent strings of PV panels, a battery charger for lead-acid or Li-Ion batteries and a pure sine wave inverter for generating mains voltage. During the daytime, the PV plant generates electricity which can be provided to the connected loads and any surplus energy is used to recharge the connected battery pack for later use.