This cuts both ways: grants are more valuable as political favors when they are immune to cancellation, and grants with objectively-established value are harder to terminate without political blowback.
You have to look up the maximum wattage for the given cabin configuration. I’ve found 30W to be about as high as I can go without it cutting out. Use a phone charger for your laptop.
This is where it’s helpful to have a multi-port charger where they’re not all high-draw.
IMO more important to go with something flat or light that won’t fall out under its own weight.