Depends on how they are used. If both are running at full speed to do all operations? Then yes. If they're used to split a task but take less cycles than a single core CPU? Then no

It's also like what consumes more battery life, a task running at 250 mhz clocked CPU or a 600 mhz clocked CPU. The 600 clock gets it done alot faster than the 250 mhz, so it spends less time in use therefore not consuming as much battery over a prolonged time.