Bees are probably a good deal faster at producing gunpowder.
As much as I'm a bee person, I'll disagree. A single alveary is indeed faster than a single creeperweed. But making more alvearies is expensive and expanding your crop farm takes just a bit of wood, EU (portable scanner) and patience.
BTW if you have harvestors with up to 2 OC upgrades, you can power them easily with Solar Panel covers. Nice, cheap and compact.