The elevation change in your question
is the key. But as to noise level, in battery mode the Clarity is just gorgeous. Like you, most of our driving is local on a daily basis and on most days we drive in battery mode EV and never use gas. It's as quiet as any luxury car and a pure joy to drive on the battery. But a number of Clarity owners, including us, have had multiple problems with a sudden loss of power to the wheels when the battery is down to '2 bars' and switches over and needs support from the engine. Also, when the engine runs to charge the battery in HV mode, it can be REALLY loud -- and this is on flat highways in Iowa with NO elevation change. When in HV Charge mode, it can just outright whine at extreme RPM levels. The loss of power issues are currently being investigated by the National Highway Traffic Safety Administration -- I heard from one of their investigators this past week. Through my dealer, I also received a statement from Honda USA that concedes that the Clarity can have a hard time holding battery on long, extended inclines -- in any mode. So, given your drive involves significant elevation change, I'd find the Clarity hard to recommend.