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Model S as a police vehicle

I think the Model S would make a good police vehicle in place of the Ford police interceptors and Chrysler chargers.

In all respects, it has a faster acceleration, more trunk space for rescue equipment, and lower operating costs and does not have the draw backs of turning into a fireball like the pre-2005 Police interceptors. (Being burned alive is probably one of the worst ways to go)
http://blog.cleveland.com/metro/2007/10/crown_victoria_police_cars_sti.html

For police officers, who have a larger degree of getting the back of their cars smashed (due to pulling cars over and another driver NOT paying attention- having a tank full of highly flammable liquid in the general vicinity is not a good idea, the Model S solves that problem by removing the flammable liquid). It's not a question of "if" they'll get their police car hit, it's a matter of "when". Not to mention the fact that if the gas tank does not explode, but ruptures, the police officer may be breathing in vapors of benzene, hexane, toluene, other hydrocarbons, etc, in which my cause long term health problems (cancer). I think the model S is the perfect car for their needs.

And the front trunk is the perfect size for bringing back a corpus delecti or two!
;)

And the silent operation makes it perfect for sneaking up on perps. And the lack of exhaust means stealth surveillance with the heater or A/C running is no problem!

And it's genetically suited to this:
http://www.guardian.co.uk/science/2004/jul/12/sciencenews.crime
and this:
http://www.patentstorm.us/patents/5503059/description.html

it is not quick enough to catch cars, and the fact that it does have a limit to its distance it can be beat on a long term chase...

plus, would you really be willing to let a Model S be hit by some idiot criminal in a chase... to elegant of a car to mess up, let the crappy Fords take the beating

Ya it may be able to PIT a car easier, but I would cringe to see a S wasted like that.

Although, I would love to see municipal cars turn electric, like police, firetrucks, ambulances, buses, and taxis even! Specially if you live in a congested city.

I bet Model S would do 250+ km/h easily if you just adjust the gear ratio to not have that high initial acceleration. After that catching bad guys is more a case of driver skill than car speed.

(I bet that adjusting optimal torque range to higher speeds you actually get better highway performance than it is now. At least for Roadster that would probably be the case).

Regardless of performance, you'll never be able to use electric for emergency services until charging time and range mimic ICE filling time and range. There's just too much at stake.

In the fire service, I could potentially see apparatus such as heavy rescue trucks and ladder trucks operating effectively as EV's, but engines and ambulances would have some serious issues. The biggest issue for all fire apparatus is the limited number of miles that are put on them. The cost of an EV drive train able to move something as heavy as a fire truck the required distance would never be made up for in fuel savings.

Ambulances frequently have longer transports, so range could become an issue. This could be resolved by simply having batteries that provide a longer range than the longest possible round trip transport. The real problem with ambulances is charging time. Most medic companies are very busy. In my area, it is not uncommon for a ambulance to make 10+ runs in a day. Current charging technology would not allow for 10+ recharges in one day for a battery pack that would be large enough to transport something as heavy as ambulance for the needed distances.

Engines (also known as pumpers) pose additional challenges. The biggest will be the fact that when they are pumping water, the engine is working harder than when the truck is driving. The longest I have had my departments engine in pump is for 52 hours at a large fire. We had to bring extra fuel for the truck in 5 gallon containers just to keep it running. There is no EV in existence that can run that long, and no charging technology on the horizon that would allow it to be recharged in minutes while running at full capacity.

Apparatus such as Heavy rescues and ladder trucks might be potential canidates for EV's at departments with low run volume, but the recharge time required to put a truck back in service after a call might still be a deal breaker.

Police cruisers on the other hand, could definitely benefit from becoming EV's. Much of their time is spent idling trying to keep speeders at bay, and they are normally only used for 12 hours at a time (in most, not all departments) The potential fuel savings for a police cruiser would be significant.

I don't believe that most police cars spend much time "chasing", outrunning, etc., etc. They turn on the lights and you are supposed to pull over, or it's busted Big Time. If you don't pull over, they have radio, at the speed of light, well, maybe a bit slower, but they can sure get ahead of you! I was driving back from Reno doing 100+ (mph) or so with about 20 other cars, and before Sacramento, there was a string of black and whites clear across 4 lanes of freeway. And we never had anyone chasing us. Model S would do fine, but I agree, you wouldn't want to get it dirty!

I think the problem of charging time is a huge issue for a municipal vehicle. For us, we can just make it home and charge over night and not have to worry about how long it takes. BUT as a police officer, if I run out of juice half way into my shift, then what? 16 hours later to fully charge my car again to be Serving and Protecting?

I love the idea, but I think its when we hit the 1000 mile range for this as a viable option for cops.

couldn't a police force have a battery swap station? (the more cars they have the more it would make sense). and if charging at 70amps, it would take more like 6 hours for a full recharge. (for the 300mile battery)

I think for those cars Tesla could quite easily make three-phase 400V@200A chargers giving 240kW charging power which charges 90kWh battery in 22 minutes (80% with less time than that).

Batteries should be able to handle that, Model S motor is 300kW motor, assuming discharge and charge capabilities are similar. 45min charging is not a problem (400V@100A 3-phase, which is not even very rare).

Within the fire service at least, 80% charge would not work. Our department policy is that any time the fuel tank on a piece of apparatus gets below 3/4 tank, it must be filled as soon as possible. The only exception to this rule is when the vehicle is on an active fire ground. On the fire ground, as soon as the vehicle gets to 1/2 tank, we start to make arrangements for more fuel to be brought to the apparatus.

Three phase 400v@200A would probably be an acceptable solution of police cruisers or other similarly sized emergency vehicles, as that does not take the apparatus out of service for an extended period of time. In the case of a large and heavy vehicle such as a fire engine, the battery would likely need to be much larger than 90 kWh, thus significantly increasing charging time on even the highest amperage of chargers.

I do think that EV's have the potential for a bright not so distant future on the law enforcement side of emergency services, the big hurdle will simply be bringing the price down to the point that the taxpayers will be willing to foot the bill.

Rifleman;
Given the fuel and maintenance costs, I think fleet ops, whether police or other, would quickly pay off.

Fire engines are another issue. I wonder if a dedicated generator for the pumps might work. And built-in connectors able to tap on-site electricity where available. Etc. Remember that the motor compartment is going to be almost empty, so there's room for various alternatives. Maybe 4+ S-style flat batteries under the frame, a drive motor for each axle, etc. Very different design concepts possible.

Hydrogen Fuel Cell / BEV hybrid for fire engines. Maybe fusion reactor later :-)

The concept of a ICE engine to power the pump, and an EV drive train actually might work for a fire engine. If the ICE engine could be switched from pump mode to generator mode, it also could serve as a range extender for those back to back calls that don't allow for recharging (the truck is never moving when it is pumping, so it only needs to have the power to do one at a time)

Fuel cells would be an interesting concept, might be a viable alternative to ICE for the pump.

From a design standpoint, most modern fire apparatus are a cab over design, with a large "doghouse" in the center of the crew compartment that covers the engine. Moving the engine to the midsection of the apparatus, and having drive motors built into the hubs would eliminate the need for this "doghouse". The extra room in the cab could be used for additional crew seating, equipment storage, or even better, eliminated to make a small, easier to drive, more agile truck. From a drivability standpoint, an EV fire engine would likely have a lower center of gravity (fire apparatus have a terribly high center of gravity) and would increase crew safety by reducing the risk of a rollover accident (about 25% of line of duty deaths occur driving to and from calls)

Onsite electricity would probably only be 120v, and would not be sufficient to power a 2000 GPM pump.

Environmental and economic issues aside, there would be allot of benefits to an EV fire engine. The quick acceleration at low speeds would match up very well to the driving needs of emergency response.

In the fire service, the "killer app" for ev's would not be economic or environmental, it would be that the EV could do the job better than it's ICE counterpart.

Actually, I was considering them for small towns, in the neighborhood of <10 square miles, very little violent crime, where the main job of police officers is handing out traffic violations. Also a town where there is very little if any crime.
As am example, in my town, it's about 8 square miles, with a total amount of roads around 60 to 70 miles, at least 3 patrol cars (sometimes 6) and each of them handle a certain "development" + 4 auxiliary officers at the station.
For small "crimeless" towns they would be perfect. Specifically for sitting there and passing out speeding tickets

@Timo
I think we won't see charging with 240kW AC any time soon.

Model S motor may draw up to 300kW but only for short periods of time, e.g. doing 0-60 in 5.6s. But cooling system for PEM and battery pack probably is designed for continuous heat development occurring at 1C charge/discharge loads. Higher charge rates surely will heat up the pack, thus shortening life times.

Another problem will be the electric + mechanical requirements of a 240kW connector. I just held a thee phase 400V@63A connector in my hands (=25kW) and it appeared unfeasible for daily use to me.


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