Should you buy a used hybrid?

Such was the case at my local watering hole: One punter was voicing his thoughts on purchasing a used hybrid. It was a move aimed at doing something to atone for his past environmental sins – he drives a full-sized SUV. The gathered throng argued the pros and cons. He maintained it was a good thing to do from an environmental perspective; others suggested a fool and his money are soon parted.

Of course, during the discussion, the inevitable straw dogs were erected and promptly torn apart by the skeptics in the group. The problem with any discussion about the validity of buying a used hybrid is that it eventually ends up revolving around one key point – the main hybrid battery and how long it will continue to service the car. It may be functioning fine at the time of purchase, but what of the future?

The problem with most of the information regarding a hybrid’s battery life is that most of the evidence is anecdotal in nature – for every taxi driver that’s managed to squeeze 400,000-plus kilometres out of a hybrid, there’s an equal number with the opposite experience. The skeptics cited an age-old saying: Every good rule must have an exception. Without some concrete numbers on a broader cross-section of hybrids – those driven by everyday Joes – most of the information is of little statistical significance.

The chap defending his decision to consider a hybrid as his next ride pointed to its fuel-efficient powertrain and the lower emissions it produces, especially the dreaded greenhouse gases. So, through the wonders of the Internet, I googled the 2001 Toyota Prius. Based on the information posted on Natural Resources Canada’s Fuel Consumption Guide website, it produces 2,182 kilograms of CO2 per year. When this number is compared with that of a regular four-cylinder Toyota Camry with an automatic transmission of the same vintage and the 4,135 kilograms per year it produces, there is an obvious benefit.

However, an eight-year-and-one-day-old Prius (currently worth between $4,600 and $6,600, according to the older Canadian Red Book) with 160,001 kilometres on the clock is technically out of warranty, and so if the battery does need to be replaced, it’s on the owner’s dime. In this case, the potential purchaser could be on the hook for anywhere between $3,500 and $4,000.

Make no mistake, the hybrid battery does wear out – not in the mechanical sense like an engine but in its ability to accept a charge and return power when it is demanded. As with a cellphone or laptop battery, the hybrid battery’s performance wanes with the number of times it is cycled and the conditions in which it is forced to operate. Toyota, for example, never fully charges the battery nor is it ever fully drained. This strategy is said to extend the service life of the battery.

Temperature is another factor that has an enormous effect on performance.

Cold weather slows the battery’s chemical reaction, which hurts its ability to deliver power and, ultimately, puts a crimp in the car’s performance and fuel economy. Likewise, the battery pack does not like to get too hot. In fairness, hybrid batteries are designed to withstand temperature fluctuations.

Another of the straw dogs suggested that replacing the main hybrid battery is akin to replacing a worn-out transmission. That’s true if one swaps the broken transmission with a new one. However, most replace a failed transmission with a rebuilt unit, which is much more cost effective. Of course, for the hybrid battery, there is the scrap yard route, but one could end up purchasing someone else’s headache. (And, don’t forget, a hybrid also has a transmission that may need replacing.)

So, what does one do?

There is no question hybrids, because of their fuel efficiency, reduce society’s reliance on fossil fuels. The hybrid experience is also building valuable know-how for the day when the car of the future uses an electric motor, hydrogen and a fuel cell. That’s the good news.

The downside is simple. If all other operating expenses (everything from the cost of purchase and routine maintenance to insurance) are equal, the fuel savings generated by a 2001 Prius amounts to $3,584 when compared with a 2001 four-cylinder Camry (the 2001 Prius has an annual fuel cost of $500 per year, the Camry costs $948/year according to Natural Resources Canada’s fuel consumption guide).

In short, the cost of replacing the main hybrid battery erases eight years of fuel savings in one fell swoop.

So, would you invest in a previously loved hybrid? Nobody raised a hand at that ad hoc forum and I’ll wager there are very few hands being raised now.

In an unusual twist, the group – a bunch that cannot agree on anything – reached a consensus: The value of a used hybrid is outweighed by the inevitable need to replace its costly battery ä at some point.

Photograph by: Kevin Van Paassen, National Post