Vaillant VPV I

What the Vaillant VPV I does

A solar string inverter turns the direct current from a rooftop array into grid-quality alternating current for the home, and feeds what the home does not use into the grid. The Vaillant VPV I range spans 1.5 kW to 6 kW of AC output, suiting arrays of about 1.5–2 kWp at the small end and 6–7.8 kWp at the large end, as installers commonly size the panels up to 30% above the inverter's rating.

In Germany, arrays of the same size produce about 1,350 to 5,400 kWh a year, assuming a conservative 900 kWh per kWp. For the smallest model, that is worth €104 a year fed into the grid at 7.70 ct per kWh, and up to €500 used at home instead of buying power at 37.0 ct.