ELWA Hot Water Using DC MPPT Controller.

No Batteries.

Use solar power directly for domestic water heating.


ELWA is a 2 kW photovoltaic water heating device. Direct current from photovoltaic modules is transferred directly to the built-in heating element and immediately converted into heat without loss. The built-in MPP Tracker ensures that the PV generator is always operated at the optimum operating point (similar to a PV inverter). For operation, no connection to the mains is required as the unit is powered by the PV generator (pure off-grid operation). The desired DHW temperature is set with a rotary knob, LED displays inform about the current device status.

Always warm water, even during bad weather.

Due to the patented boost-backup function, hot water supply can be guaranteed even during bad weather. This makes it possible to completely switch off the conventional heating system in summer. This also increases its lifespan.

For commissioning the boost-backup function, ELWA can be easily connected to a mains socket. There is no feed-in into the grid, so it does not need a metering point like a grid-connected PV system.

Technical data

DC nominal power0-2000 W with MPP tracking
DC inputs1 string, 4 – 8 modules, MC4
AC boost power750 W for boost-backup
Mains connectionSingle-phase, grounded plug, 230 V, 50-60 Hz
Dimensions (WxHxD)130x180x600mm with heating element
Protection classIP 21

The Downside

ELWA has not gotten North American approvals yet. However, you can apply for a field evaluation with the ESA.