Solar power for hot water and increased self-consumption
AC ELWA 2

Linearly controlled water heating device for grid-connected photovoltaic systems
AC ELWA 2 is a 0 - 3.5 kW linearly controlled water heating device for grid-connected photovoltaic systems and is the successor to our proven AC ELWA-E. In order to maximize the self-consumption of your current PV system, AC ELWA 2 harnesses the system's surplus photovoltaic energy to heat your water. Increasing self-sufficiency simultaneously safeguards against unpredictable or rising operating costs. The PV feed-in power can be regulated to zero by the linear control.
Our trusted optional hot water backup function is included in AC ELWA 2: In the absence of sufficient sunlight, energy from the public power grid can be used to heat the water to the desired temperature. AC ELWA 2 can be installed in hot water and buffer storage tanks.
Advantages of AC ELWA 2 over AC ELWA-E include:
- More power: 3.5 kW as opposed to 3.0 kW
- Very straightforward installation: Heating element and control unit can be installed one after the other
- Ease of use thanks to the touchscreen display
- Flexible control options: in addition to RJ45/Modbus TCP Ethernet, RS485/Modbus RTU, PWM-in, galvanically isolated relay contact
- Integrated external temperature sensor
- A second standard heating element can be controlled
- Even more compact design than its predecessor
- No cable, fixed wiring and a shockproof plug

Winner of the German Design Award 2024
"Excellent Product Design – Energy"
Efficient heating meets outstanding design: In the category of "Excellent Product Design – Energy," AC ELWA 2 has been awarded with the title "Winner".
Jury Statement
"AC ELWA 2 transforms surplus solar power into hot water, thereby increasing self-sufficiency. It's a purposeful product that strikingly combines high-tech performance with a clear and dynamic design language," states the jury of this prestigious award, acknowledging our linearly controlled hot water preparation device for grid-connected photovoltaic systems.
3.5 kW
Maximum PowerTouch Display
Easy ControlWiFi Ready
Smart IntegrationApplications of the AC ELWA 2
Flexible solutions for every heating scenario

AC ELWA 2 in combination with my-PV WiFi Meter
In combination with my-PV WiFi Meter, AC ELWA 2 only uses surplus energy from your photovoltaic system. The heating power of the heating element is controlled linearly so that almost no energy is fed into the grid and your self-consumption reaches a maximum.
The connection to the router is made via a patch cable or wirelessly via WLAN.
AC ELWA 2 in combination with battery storage
AC ELWA 2 is compatible with many commercially available battery storage systems. It takes into account the optimal use and prioritisation of photovoltaic energy.
The battery storage is always charged first. As soon as the battery is full, AC ELWA 2 takes over the storage of excess photovoltaic energy in the form of hot water. Water is the cheapest form of storage and can be perfectly complemented with chemical storage batteries. This way, the electricity you generate stays with you and is not fed into the grid.


AC ELWA 2 in combination with Smart Home
Thanks to the open-system control, AC ELWA 2 also communicates with commercially available Smart Home and energy management systems. Control is carried out by the Smart Home system. This way, even complex control systems with priority setting by the consumers can be realised.
In residential buildings, systems with multiple devices work together on this basis. Remote monitoring and energy cost billing are possible at the apartment level.
AC ELWA 2 in combination with dynamic electricity tariffs
On days with low sunlight, the AC ELWA 2 can utilize cheaper electricity from the public grid for heating supply.
Anyone with a photovoltaic system and a dynamic electricity tariff can use the my-PV DTO to access cheap energy from the grid for heating even on cloudy days or at night when the PV system doesn't provide enough electricity. The my-PV DTO is easily activated in the my-PV Cloud and controls heating automatically – based on the lowest market electricity prices. The my-PV DTO works in combination with all IoT-capable my-PV devices.
