Glossary:MPP inverter
Getting the most power out of a PV (or solar) cell or wind turbine isn't straightforward. The output voltage will be maximum if you draw hardly any current, and if you draw as much current as you can the output voltage will drop almost to zero. In either case the power delivered (voltage × current) will be minimal. An MPP or Maximum Power Point controller or inverter will continuously adjust the current drawn in order to maximise the power, for example to charge a battery or deliver power to the National Grid.