Sunward, and in some exoplanets, solar power is a fairly reliable method to generate electricity. While not always potent, the sun shines bright enough to generate power on Mars, the Lunar surface and other locations scattered around the inner system region. Solar power can also be artificially stimulated for chargers and other devices, though obviously, simple witricity charging or self-charging batteries are often better. The portability of this is found in the Solar Recharger (p. 155 Gatecrashing) a backpack unit with an extendible photonic film/smart material panel which can generate power at a similar rate to nuclear batteries - though with slightly less rare materials and no effective limit on lifespan. While a backpack unit is useful for many things, like other tech there is no reason such devices cannot be installed in certain morphs.
Solar Panels: Based on the Solar Recharger, this simple augmentation embeds collapsible solar panels into the synthmorph, which can be extended as a Quick Action to begin drawing power. The augmentation uses a pair of slightly shorter (about 1 meter) panels instead of a single longer panel, having an appearance a bit like wings when unfurled. These panels generate power in sunlight similar to the recharger or a nuclear battery and can top off internal batteries or small devices connected via PAN in short amounts of time - or allow a morph with an implant such as Eelware to charge larger devices they are connected too. [Trivial]
Solar Panels are common in Martian synthmorphs who wish to live "off the grid" but don't want to carry an external charging device with them, or in a couple of space-based Synthmorphs (such as the Courier) as an add-on for those who might be catching enough light to charge internal power. Gatecrashing synths have also started investing in them, as a way to reliably generate battery power in terrestrial environments, with the low cost usually being worth it even if they end up in a locale not with solar power.