Synchrotron-based soft x-ray spectroscopies are powerful techniques to investigate the electronic structure of a variety of material systems. In particular, soft x-ray absorption (XAS) and emission (XES) spectroscopy, as well as their combination resonant inelastic soft x-ray scattering (RIXS), are uniquely suited for the investigation of applied energy conversion devices, including photoelectrochemical devices, thin-film solar cells, and batteries. To aid in the development of such devices, in situ and operando studies are often required to answer the pertinent materials questions, especially for information about surfaces and interfaces. Due to the photon-in-photon-out nature of XAS, XES, and RIXS with soft x-rays, it is, in fact, possible to investigate gaseous and liquid samples as well, making such in situ and operando investigations possible. However, since these spectroscopies and the corresponding synchrotron beamline environment usually involve ultra-high vacuum (UHV) conditions, this requires the development of sophisticated environmental cells, high-efficiency spectrometers, and optimized spectroscopy approaches. For example, the investigated materials are often very sensitive to x-ray radiation, which requires careful and custom-tailored experimental strategies. The presentation will discuss our recent progress in developing the experimental tool chest necessary for such in situ and operando soft x-ray studies, demonstrating how these techniques give insights into the electronic and chemical properties in the solid, liquid, and gas phase, as well as their interfaces.