As someone who had an 80's diesel car as his first, I can verify that even leaving them in a high school parking lot during a cold winter school day in Maine is a bad idea.

I had to wait about a week for the weather to warm up before the glow-plugs were enough to start it.

However, I believe a Tesla is a different case. I always keep my car's fuel tank above half-filled to preserve the fuel filter (and you should too). While the Tesla might lose some charge during the day in a parking lot or overnight, I can't imagine it would be a seriously substantial amount.

How does keeping the tank fuller preserve the filter? All the crap in there sinks to the bottom anyway, no?

I think he meant the fuel pump. It can overheat if fuel levels get too low.

Correct, I mis-typed. Also, the more room there is in the tank, the more room there is for water vapor in the air filling the rest of the tank to collect. This can cause rust.

Not really, any more. The fuel is winterized at point of purchase, so fuel geling is rather unlikely these days (and if it does, there are additives that will un-gel it.

Modern glow plugs are also much better. In my VW TDI, at 10F the glow plug cycle is only about 3 seconds, and then it fires right up. No glow plugs need at all above 35F.

Usually you're right. Unfortunately we had a bit of a facepalm last year here in MN when the diesel-powered school buses wouldn't start at -10F or something. It turns out that in the state's hurry to push biodiesel on municipal vehicles, someone forgot that it gels at higher temperatures than "normal" diesel.

Thousands of schoolchildren were quite happy, though.

Same for our 2011 TDI. Never had to worry about fuel or engine issues, even in quite cold weather (not arctic, but we live in RI, so there are some cold winter nights to contend with).

Regarding the fuel, there are some details, along with some discussions of operating temperature, in the Wikipedia page: http://en.wikipedia.org/wiki/Winter_diesel_fuel. The temperature ranges suggest that you're unlikely to have serious issues with your diesel car, if you buy fuel appropriate for the season. The inconvenience factor of owning a diesel car compared to a petrol one is pretty minimal, as far as the sort of cold weather that most people who might consider buying a car (as opposed to something with tracks, skis, or 4' tyres) will generally encounter.

We had most of december and january below -15C sometimes down to -30C and diesel cars had no problems. Most problems were caused by guess what: batteries not giving enough juice to start. Diesel cars, having bigger batteries, were actually more reliable.