String inverters, and of late string inverters with optimizers, have become very popular. The technology revolves around long strings of panels or optimizers connected in series that run to inverters where the high DC voltages are converted into usable AC electricity.
This way of working has its limitations, be that with regards to safety, the amount of effort required to install the system, or constraints when designing and expanding the system.
The principle is simple: add an MPPT to panels, convert the direct current to the alternating current right at the source, and then use the much safer AC cable runs to connect to the national electricity.
High DC Voltages increase the risk of electricity arcs and fires. By inverting to AC right at the source, these risks are decreased substantially. There are also no expensive DC cable runs and control gear.
By continuously monitoring each panel, Hoymiles allows quick identification of faults in the system. The result is lower downtime and decreased operations and maintenance costs as the affected panel is pinpointed almost immediately. The monitoring platform is also free of charge – for life.
Because each panel has its own MPPT, failure in one does not affect the other panels in array. This means that the common causes for loss in yield and efficiency such as shading, bird droppings and dirty panels are mitigated with the use of microinverters.
Because of the modular nature of microinverters, the system can be expanded at will allowing for the optimal use of all available roof space. There are no minimum string lengths to worry about and the inverters are installed under the panels thus eliminating the need for unsightly power units in a controlled designated area.
Standard 12 Year Warranty
Typical string inverters come with a 5 year warranty. Hoymiles comes with a 12 year warranty standard – and can be extended to as long as 25 years.