Pretty much all African safari lodges and camps have electricity, either by power lines, generator or solar power. Some have power sockets only in the main area and not in the tent, but you will have electricity to recharge all your electrical devices and cameras.
However if you decide to do an African mobile safari, you will need to face a different situation. A mobile camping safari will take you to private and public campsites and many will not have power. That is the moment when it becomes really adventurous and challenging, realizing where electricity comes from, not from a box in the wall, it needs to be generated.
For these kinds of adventures get yourself an inverter. An inverter makes that you can use the battery power of your safari vehicle to recharge your laptop, camera, phone and other devices. But you can only recharge while driving. The devices use too much power and the inverter will stop working when the vehicle’s engine is not running. You need to get your mind around that quickly, otherwise you will end up with no charged camera batteries and laptops. It requires thought through anticipation and planned energy use. It can be useful to have your laptop with you on game drives to upload images and recharge immediately to have a fully charged laptop when back in camp. That can lead to wonderful situations like standing under a tree with a leopard, watching the animal through the open pop up roof while uploading your images from the morning onto your laptop to empty your memory cards and use the rest of the game drive to recharge your computer.
It is a very good survival training for photographers to conquer any situation and still getting the images you want.
The same thoughtful process applies to light sources you want to have when it gets dark. They also need to be recharged while driving and not to forget the fridge you carry on the vehicle to keep your food fresh and eatable.
It is a mind changing experience to be for some time the generator of the electricity you need. It is a consciousness enhancing process you can benefit from in many situations, also back home with a power socket in every corner of the house.