🎉We can now proudly present the winners of the TAPAS Community Challenge 2018! 🎉
Congratulations to Team "Wireless Charging" (idea 56). We are really excited for all finalists and a really big thank you to all participants for your interest in this challenge!

We got over 200 submissions! 65 ideas got one or more TAPAS boards, 10 submissions were presentation-ready.
And now we have 5 finalists! YEAH 😃 The finalist's idea numbers were 40, 56, 68, 212 and 213.
What's next?
We are now preparing the next steps for you, the community. Please stay tuned!
We are working on a forum and a separate webpage. If you have any question please don't hesitate to contact us via email!

Auxiliary battery charger for off-grid van

Camper vans are becoming a popular travel option among the youth, they are like tiny homes. One of the challenges of building one is getting power for all the equipment: lighting, water pumps and heaters, fridge, etc. This is usually accomplished by having an auxiliary battery which is charged via solar panels on the roof. However, sun is not always available and running out of power is really troublesome. The idea of this project is to use excess power from the van's battery and alternator to charge the auxiliary one. The important thing is to prevent van's battery from draining so you could always start the engine. Only excess energy generated when idling in cities or traveling longer distances would be used to charge auxiliary battery.


Technical setup of the project would include:

  • Van's battery system or a simulated environment with DC power supply
  • Auxiliary battery
  • TAPAS board
  • Raspberry pi computer with battery status display
  • Jurgis Balciunas
  • Apr 26 2018
  • May 8, 2018

    Admin Response

    this idea will get one TAPAS dev kit

  • Admin
    Nora Schille (TAPAS team) commented
    May 03, 2018 11:17

    Hi Jurgis,

    thanks for your  submission! Great idea!
    Can you might give us some more information about your idea:
    Why do you want to use TAPAS & raspberry pi for charging management? 
    What's your motivation to build your own charger and not just use one off-the-shelf?

    Thanks alot :-)

    Nora @TAPAS team

  • Jurgis Balciunas commented
    May 03, 2018 18:08


    Thank you for your reply.

    I far as I am aware, there are no off-the-shelf chargers that regulate charging current to maintain certain voltage on the input (to prevent depletion of the main battery), which is the main point of the idea. Although, TAPAS board is a 3 phase inverter oriented at driving 3 phase motors, I think that it is still suitable for DC charging application since paralleling all three phases would allow higher drain currents and reduce power dissipation.

  • Admin
    Nora Schille (TAPAS team) commented
    May 08, 2018 11:23

    Hi Jurgis, 

    thanks for your additional explanation. Our team decided to provide you one TAPAS board.
    One of my colleagues will message you shortly.

    Nora @ TAPAS team

  • Jurgis Balciunas commented
    May 08, 2018 14:54

    Thank you!

  • Admin
    Nora Schille (TAPAS team) commented
    June 04, 2018 13:43

    Hi Jurgis,

    how is it going? Do you need any help regarding the realization of your project?
    Here is just a friendly reminder that submission deadline for your presentation is on 24th of June. :-) We are really excited to see your progress! 
    Please post the progress within your idea board submission.

    PS: We want to do a community call with you! Please use our doodle to find a date which fits best for you. :-)

    Nora @ TAPAS Team

  • Jurgis Balciunas commented
    June 11, 2018 12:17

    Hello Nora,


    Sorry for the late reply, I was busy with my graduation thesis. But now that it's done, I should be able to finish this project on time.


    I have already received the TAPAS board, but unfortunately, some of the transistors on the bottom are chipped and cracked. Probably during shipping. At least one channel seems to be OK and I think I should be able to still use it to demonstrate the idea. I'll let you know about the progress.

  • Admin
    Nora Schille (TAPAS team) commented
    June 12, 2018 06:58

    Hey Jurgis,

    that's great to hear! We cross fingers for your thesis :-)
    Please let us know asap if you need a replacement (best way through the support email tapas.support.ct[at]siemens.com)!


  • Jacqueline Hofmann commented
    June 20, 2018 12:43

    Hey Jurgis,

    Please keep in mind that the submission deadline for your presentation is on 24th of June! We are already looking forward to seeing how you brought the TAPAS board to life! :-) Remember that you still have time to work on the implementation of your idea after the submission!

    Please upload your presentation and everything you want to share with us in your idea board entry.

    Good luck :-)

    Jacqueline @ TAPAS Team

You can read the official challenge FAQ here!