Some experiments are being done, but the concept has been mostly scrapped now. SG coaches have higher maintenance requirements and not suitable for high speed runs ( Basically they nullify all the advantages of the LHB coaches). Also, the FIAT bogie design is not really good for adding generating equipment below the coach. That's why now the only focus is on developing HOG systems, and integrating the diesel generator into the SLR coaches.
RCF did manufacture some LHB coaches with roof mounted solar panels for power generation, but as such the concept of self-generating LHB is almost scrapped now.