I don't know what average distance an LA city bus travels per day, but the average range of all the LA city buses (which are predominantly natural gas powered) is 385 miles. So the BYD bus gets 1/8th the range which seems very low to me. I am not a battery/bus expert but I don't think it is as simple as adding more batteries under the bus. A whole host of issues will need to considered: cost, extra weight, clearance, safety, charging times, etc...