Using ROHDE kilns with photovoltaics
An electrically operated kiln is one of the larger consumers of electricity in the household. This means that a photovoltaics system offers savings potential comparable to that of an electric car or a heat pump.
By using your own power utilisation, you can save considerable electricity costs all year round, even in winter and when it is cloudy.
Current ROHDE controllers are optimized for operation on a PV system. With the ST 310 and ST 411 controllers, you can use any ROHDE kiln built in 1994 or later with solar power.
This allows you to fire more sustainably and reduce your electricity costs at the same time.
Switch now: Photovoltaics-optimized control system
With a photovoltaics-optimized control system, you can use any ROHDE kiln built in 1994 or later with solar power.
The ROHDE ST 310 and ST 411 controllers can be switched between conventional firing and SolarReady mode.
The new ST 310 and ST 411 controllers are available from all ROHDE dealers.
Firing ceramics with solar power:
Questions from ceramicists
How much do I save on ceramic firing thanks to my own solar power?
The actual savings depend on the electricity price, the size of the kiln, the type of firing and the output of your PV system.
If the PV system and kiln are well coordinated, the proportion of self-generated electricity is up to 95%. Your savings on electricity costs are correspondingly high.
Examples from practice
What does SolarReady mean? Why do I need a photovoltaics-optimized control system?
A ceramic kiln controls the temperature by switching the heating elements on and off. With conventional control systems, this works so quickly that a photovoltaics system is overwhelmed by the speed.
With a photovoltaics-optimized control system, these switching cycles are extended so that they harmonize with your PV system.
Both controllers (ST 310, ST 411) can be switched between conventional firing and photovoltaics-optimized.
Does photovoltaics firing have an influence on the firing curve or the result?
At the beginning of the firing process and in the low temperature ranges, the firing curve is still noticeably wavy compared to the smooth target curve. This changes long before the temperature ranges relevant for the ceramic quality (quartz inversion) are reached.
Before the market launch, we tested photovoltaics-optimized firing intensively in practice for a year in our own laboratory and in some ceramic companies: there are no differences in terms of the results.
What changes will there be to the power supply for my kiln?
Current PV systems are grid-connected. This means that the kiln is still connected to the electricity grid in the house. If sufficient electricity is available from the PV system, this is used as a priority and less electricity is drawn from the grid. If no or too little electricity is available from the PV system, the electricity comes from the grid as before.
There is no interruption in the power supply. Not even with ceramic firing.
Which ROHDE kiln is optimal for my photovoltaics system?
As a rule of thumb, the so-called peak output of your photovoltaics system should be 2.5 times the connected load of your kiln.
This means that an Ecotop 60 is the right size for 9.9 kW photovoltaics systems. A TE 200 S would be a perfect combination for the larger 20 kW photovoltaics systems – especially those used in combination with a wallbox.
Instructions for controller upgrade ST 310 / ST 411
Do you already have a ROHDE ST 310 or ST 411 controller?
Then you can configure it for operation with a photovoltaics system with an upgrade and a simple parameter change.
Check the Firmware version of your controller to find the correct instructions.
The Firmware version of your controller is shown on the display at start-up.
ST controller from mid-2021
- ST 411 controller with Firmware F6.20 to F6.22
- ST 310 controller with Firmware F1.02 or F1.03
They require a simple upgrade using the latest ROHDE SolarReady Firmware and subsequent parameter conversion.
Step 1: Upgrade the controller using the Firmware (.HEX file)
- Download the .HEX file: FIRM310A.HEX for the ST 310 controller or FIRM215A.HEX for the ST 411 controller.
- Copy the .HEX file to an empty and formatted USB stick.
Note: The file name must not be changed! - Switch off the controller.
- Insert the USB stick into the controller.
- Press and hold the buttons <> at the same time.
- Switch the controller on and hold the buttons <> button until 2 dashes “- -” appear in the display. You can release the buttons.
- A countdown starts counting down on the controller display at 95
- Wait until the countdown reaches 0. Do not press any buttons.
- The countdown runs through again quickly and the controller then restarts automatically.
- The controller displays the new Firmware version and the thermocouple type tC.S after the automatic restart.
Note: The new version of the Firmware must be higher than the previous one. - You can now remove the stick and use the controller as usual.
Note: Check the parameters that you changed before the Firmware upgrade and adjust them again if necessary.
Step 2: Converting the parameter set to photovoltaics control
- Switch off the controller.
- Press and hold the START/STOP button.
- Switch on the controller and continue to hold down START/STOP until …
- …the thermocouple type tC.S is shown in the display. Wait 1 second.
- You can release the buttons. P14 is now shown on the display.
- Use the arrow buttons ↑↓ to press until P16 appears. P16 is the parameter for the “Standard” or “SolarReady or photovoltaics” control type.
- Use the > button to go to the parameter set; 0 appears on the main display.
- Use the ↑↓ arrow buttons to change the value to 1, which stands for the “SolarReady or photovoltaics” control mode.
- Press the START/STOP button to save the changes.
- The display goes dark and the controller restarts.
The controller is now in “SolarReady” photovoltaics mode.
Caution: If you do not press a button for 30 seconds during input, the display shows “tout”, for “time-out”, the controller beeps and the changes are not accepted!
ST controller from the end of 2023
- ST 411 controller with Firmware F6.23
- ST 310 controller with Firmware F1.04
You can make your kiln SolarReady by simply changing the parameters.
Conversion of the parameter set to photovoltaics control
- Switch off the controller.
- Press and hold the START/STOP button.
- Switch on the controller and continue to hold down START/STOP until …
- …the thermocouple type tC.S is shown in the display. Wait 1 second.
- You can release the buttons. P14 is now shown on the display.
- Use the arrow buttons ↑↓ to press until P16 appears. P16 is the parameter for the “Standard” or “SolarReady or photovoltaics” control type.
- Use the > button to go to the parameter set; 0 appears on the main display.
- Use the ↑↓ arrow buttons to change the value to 1, which stands for the “SolarReady or photovoltaics” control mode.
- Press the START/STOP button to save the changes.
- The display goes dark and the controller restarts.
The controller is now in “SolarReady” photovoltaics mode.
Note: If you do not press a button for 30 seconds during input, the display shows tout, for “time-out”, the controller beeps and the changes are not applied!
Sustainable firing – managing the kiln on the move
With an up-to-date controller, your ROHDE kiln is not only SolarReady, but can also be used with the app at the same time.
Use the ROHDE myKiln app and keep an eye on your kiln at all times, no matter where or when. Thanks to the app and SolarReady, you can see immediately how much you have saved by firing with solar power.
