House power demands obviously fluctuate but during peak demand the battery is likely to run down and require the engine. My colleague said he went a week on a Prius and used 5 gallons of gas to power his house so the car probably ran an average of an hour a day. Compared with the noise made by most home generators, the car noise would be quite modest (and the car is already paid for and maintained). People here pay $100 a year for their "portable" generator to be transported to a power equipment dealer for an annual tune-up (which probably costs an additional $100+). They still cannot be depended upon when the power fails and make a great deal of noise.
@Prabhakar, I think you raise an intersting question here. If cars are being used just for commuting, whouldn't we be looking at car pooling (or mass transportation), rather than EVs?
You are absolutely right.
But I think some people still like "owning" things. And if they do want to own an EV, one of the key reasons stopping them from doing so is the range anxiety.
In fact, I think it's quite genius, on the part of BMW, to come up with this idea -- let people buy and "own" an EV, and when the EV's range becomes an issue, the carmaker will let you give you a loaner with combustion engine.
@sheetal, i know. It does sound idiosyncratic for anyone wanting a new car not based on performance but on dashboard.
And yet, when all things were equal, consumers -- young and old included -- do make choices, sometimes, based on what they care about most in their everyday life: your car's connectivity to smartphones or to the outside world, not to mention the size of a cup holder inside car...
Okay, however in that case, I'm not sure how quiet the car would be.
An efficient car needs something on the order of 12-14 HP to travel at a steady 50 mph. When a car is running at 50 mph, the engine is hardly quiet. Of course, as long as a hybrid is running on battery juice alone, it's quiet, but when you're powering home HVAC, kitchen, lights, and appliances, you're not going to benefit from any regenerative braking. So the engine in that Prius will be running at least some of the time, when the load is substantial.
So, 12 to 14 HP translates to 8.9 to 10.3 KW. A generator sized to run your house, without a lot of rewirirng to switch off heavy loads during a power outage, needs at least 7 KW. So we're in the same ballpark. I don't think you can assume the car will be idling out there in the driveway. Not much of the time anyway, especially if you live in an all-electric house, with heat pump, electric hot water heating, and running HVAC in summer or winter.