Blue Line


December 1, 2015  By Dave Brown

1158 words – MR

To charge and serve
No electric police cars anytime soon

by Dave Brown

The Los Angeles Police Department has announced it is acquiring two plug-in electric cars as test platforms. The BMW i3 and Tesla Model S, both on loan from their manufacturers, will be used for research and public relations, outfitted in LAPD colours and fully equipped with a light bar and siren package.


Electric cars are wonderful. They save the environment. All your friends and neighbours should drive one – but will you be driving one as a regular patrol cruiser anytime in the next 20 years? Not likely.

They are admittedly trendy, especially in image-conscious places like California (and one presumes, plug-in stations will soon start popping up around Parliament Hill.) Battery technology is improving every year. However, there needs to be a massive revolution in plug-in technology before they are suitable for daily patrol. Here’s why.

{Get used to waiting (and waiting)}

Electric cars work best for owners who drive 100 kilometers or less a day and then plug them in at night. This is exactly opposite to what police agencies require. Once the batteries are depleted, it will be a minimum of three hours for just a quick top-up charge – assuming you make it back to a 220-volt plug-in station – and at least 14 hours for a full charge if plugged in to a regular 110-volt home outlet.

“Supercharger” stations, which can push out 400 volts and charge to 80 per cent capacity in less than 30 minutes, are starting to pop up in the US – but as any owner of a laptop with lithium batteries knows, 80 per cent charge does not translate to 80 per cent range. If anyone thinks these new 400-volt charging stations are the answer, put four washrooms in a police station of 100 people and invite everyone to use them for 30 minutes. See what happens.

One common figure touted by manufacturers is the return on investment, or the number of kilometers it will take to pay for the higher cost of acquisition. This doesn’t apply to police. Before any other cost is factored in, an agency will need a third more cars just to allow for down time while charging.

{Get used to walking}

Some of the newer electrics can travel as many as 300 kilometers before they need recharging. With better batteries and future technology advancements, that range might even double in a few years – but that figure is always best case. Do a couple of high-speed calls, sit at an accident scene for a few hours with heaters, radios, and lights in the winter, and that theoretical range drops dramatically.

When your batteries drop below 10 per cent, you are finished for the night. One doesn’t pull into a gas station and top up; you are due for at least a six-hour wait at a 220-volt station.

{The cost of battery replacement}

The manufacturers like to skip over issues like projected battery life and cost of replacement battery packs. Consider that the batteries can be as much as half the cost of the vehicle, so a replacement pack is going to run $15,000 minimum and likely much more than that. With heavy use, this replacement will have to be done every three to five years.

Lest you think the costs of battery replacements don’t have to be factored in to police purchases because the vehicle will be traded in long before the packs are depleted, consider two issues. One, battery life progressively deteriorates from the moment of manufacture. This means that a three-year-old vehicle might produce less than one-third its original range.

Second, a three-year-old electric car is almost worthless. New owners will be faced with an almost immediate five-figure cost. The costs must still be figured into the depreciation regardless of whether an agency replaces the battery packs.

If your department is lucky enough to be able to afford a $90,000 Tesla Model S, replacement battery packs are projected to be well over $20,000, and that is assuming new battery plants and improvements in technology can significantly reduce the future costs. Constant use day and night and continual draining of the packs to their minimum will significantly reduce battery pack life.

{Electric cars are not that clean}

Electric energy may cost less per kilometer than gasoline but there is always a cost – and not every cost can be easily calculated. Everyone talks about how clean the electric car is, but just because it doesn’t have tailpipe emissions doesn’t mean it is not harming someone. Many US states still generate some of their electricity through coal-burning plants. In fact, most of California’s electrical energy is imported from neighbouring states so one could suggest that if you factor in the environmental cost of burning coal and the physical cost in human lives to mine it, Californians are shortening the lives of their neighbours just so they can drive plug-in electric cars.

Wind turbines don’t always deliver everything they promise either. Using conservative numbers, one wind turbine can generate only enough electricity to recharge about 1,700 electric police cars in a year.

{Electric cars are not that fast}

Sure they have a lot of torque and that does get them rolling quickly. Gasoline engines generate their greatest torque between 2,500 to 4,000 RPM. Electric motors generate their greatest torque at 0 RPM. This is why some electrics have such insanely fast acceleration numbers – but just because you can accelerate to 180 KPH quickly doesn’t mean you can stay there very long. Once air resistance begins to take hold, electric motors do not last long at speed and will suck up battery juice at a prodigious rate. Both motors and batteries overheat quickly at top speeds.

In real world conditions, you better hope that a pursuit is resolved or terminated within 10 minutes because that’s about all you are going to get – and that’s on a fresh charge.

{An electric glimmer at the end of the tunnel}

For the agencies that feel they must plug into something, hybrid technology and the new plug-in hybrid cars show much more promise, at least until there is a serious revolution in battery technology. The cross-over – gasoline engine charging batteries as you patrol – is a light at the end of a dim tunnel. They have much of the torque of plug-in electrics and won’t leave you stranded at the side of the road or waiting in line for the charging station.

Another plus for police is that they are now available in a respectably sized SUV. Slap a green sticker on the side and listen to your citizens sigh.

So, without even touching on the greater cost of repairs and the potential hazard of all that amperage sitting there after a bad traffic accident, I am predicting full electric cars will not be ready to patrol our streets for decades. Saving the environment for future generations is a laudable goal, and plug-in electric cars are wonderful tools for special service vehicles, parking in front of high schools or driving in parades. They just don’t belong on patrol.

Ask me again in 20 years.

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