I mostly just use my bike for commutes and charge in the middle. So, the one-way matters. But sometimes, I can drain like 80% of the battery going one-way and other times its like 20%. Of course this will depend on how much assist you use. With a good tailwind, I’m pedaling hard enough the assist might do very little outside of accelerating after stopping. With a bad headwind, the assist might be at/near 750W nearly constantly (and still sometimes dipping down below 20mph) and my contribution is pretty negligible. I do live in a relatively flat area nearish to the coast… so winds speeds might be a bit more variable here.