DEAR CAR TALK: I love your column. Learning about cars is so much easier with your sense of humor.
We own a 2018 BMW X5 40e gasoline-electric plug-in hybrid. According to BMW, using the 3.5 kWh charger on a standard household outlet (which I have read uses 1,440 watts) takes 3 hours and 45 minutes to charge the car from a depleted state. With that charge, I get 14-19 miles of all electric power before the car turns into a regular hybrid.
Where I live in (expensive) Rhode Island, electricity costs 22.67 cents per kWh, including taxes and fees. So I'm trying to do some calculations. Would the correct formula be: The watts (1,440 per kWh) divided by 1,000, times the hours (3.75), times the cost per kilowatt hour (.2267)? Would that tell me how much it's costing me to charge my battery?
If so, this equals about $1.23 per charge. That would be great for a range of 14-19 miles on a charge, less than half the cost of a gallon of 91 octane fuel.
The alternative would be to multiply the kilowatt hours (3.5) times the hours (3.75), times the cost per kilowatt hour (.2267). That would mean it's costing me $3.17 a charge, which would be awful, because it would be more expensive than premium gasoline.
Is one of my formulas correct? Or is there an easier way to calculate the cost of running my car on electricity?
— Rick
DEAR RICK: You know what's worse than spending an afternoon screwing up a complicated math problem. Finally figuring it out and realizing that your car costs more to run on electricity than on gasoline.
Forget your formulas, Rick. The easiest way to calculate your cost per mile is to start by looking up how many kWh (kilowatt hours) your car requires to travel 100 miles. That's a standard measure for electric cars, and you can find it by going to the EPA's consumer website, www.fuel-economy.gov.
You bought a big, heavy SUV, and it takes 59 kWh to push that BMW X5 100 miles. That's on the high side. Just for comparison, the Chevy Bolt requires 28 kWh to go 100 miles.
Anyway, you then multiply your car's kWh/100 miles (59) times your cost per kW (0.2267, which is on your electric bill), and you find out that it costs you $13.38 to run your car 100 miles on electricity.
If you divide that by 100, you get your cost per mile, which is about 13.4 cents. To compare that to gasoline, take the local cost of a gallon of gas (the X5 requires premium fuel). Let's call that 3 bucks a gallon.
According to the EPA, your X5 hybrid gets 24 mpg on gasoline, so you'd need 4.17 gallons to go 100 miles. Multiply the number of gallons times the price per gallon, and you learn that you need $12.51 worth of fuel to go 100 miles, or 12.5 cents a mile.
So it costs you a penny more per mile to run on electricity. Doesn't that frost your shorts?
The problem, as you seem to understand in your letter, is that the cost of electricity is pretty high in your state, and the price of gasoline is pretty low. In many parts of the country, running a car on electricity costs quite a bit less than running on gasoline. But it's worth doing the calculations before you buy.
Of course, with a plug-in hybrid, Rick, you get the best of both worlds. You can plug in your car at night in your own driveway, let the car charge up while you're sleeping, and drive around feeling good about helping the environment.
Plus, you get to enjoy the occasional stop at the gas station, where you can pick up a 13 gallon bag of Cheez-Its, a 178 ounce Arizona Ice Tea, and spill some gasoline on your trousers. Live it up, Rick!
DEAR CAR TALK: My Volvo 740 GLE's timing belt just broke and my valves are bent, according to my mechanic's diagnostic test. Is there any way that I can just inexpensively have the valves fixed or replaced, instead of buying a whole new engine? My car has over 150,000 miles on it. Thanks.
— Gloria
DEAR GLORIA: There's no inexpensive way to fix the valves. Bent valves are not like a gate latch that you can straighten out with a hammer and pair of pliers. Valves have to fit precisely in the openings made for them in the cylinder head. And once they're bent, they're ruined, whether you bent one of them or all 16.
However, you don't have to buy a whole new engine. You can simply buy a replacement cylinder head. And by "simply," I still don't mean "cheaply." You'll either need a used cylinder head from a junkyard (aka auto recycling center), or you'll have to buy a remanufactured one from a company like Jasper.
If you can find a good used one, there's no reason not to try it. After all, the rest of the car has 150,000 miles on it. By the time you find it, have it checked out, clean it up, install it and put on a new gasket and timing belt, you're probably in for at least $1,000.
A factory remanufactured cylinder head will probably cost you twice that much when it's all done. But you'll get a warranty with it.
I'm guessing you don't have a mechanic you love, Gloria. If you did, you would have asked him these questions. So try searching for a great mechanic in our Mechanics Files database (www.mechanicsfiles.com). Put in your ZIP code and search for a highly rated Volvo mechanic in your area.
Someone like that will probably be more willing than the dealer to work with you, look around for a good used cylinder head and try to save you some money. But don't walk in and try to hand him your pliers, Gloria, or you'll just scare him off.
Ray Magliozzi dispenses advice about cars in Car Talk every Saturday. Email him by visiting:
cartalk.com
HomeStyle on 03/23/2019