I have just found out a safe and painless way to defrost the windshield and to warm up the van. I use a portable propane heater - one that is used for camping and indoor use.

Instead of going out in the cold - start the engine - and sit there shivering with the foot on the pedal (there's no choke to adjust the engine speed) to get the engine going, I just lit up the heater. In 10 to 15 minutes, the inside is toasty and warm. When I am ready to roll, I start the van and drive away slowly. In no time the engine warms up without the unnecessary wear and tear.

I use a propane tank adapter for refilling the bottles to save money, and it costs pennies to do.

Yes I heat up too.

But just using electric heaters and once they are installed they are really handy to use.
My car has a 0,75 Kw electric heater inside the engine block which warms the cooling system. Another 1,6 kW heater heats up the interior and they both are connected to a plug which situates in the front bumper.
So before starting I just plug it for some time.

Not advertising but some examples:
http://wup.defa.com/en/wup_products_interiorheaters.html
http://wup.defa.com/en/wup_products_preheaters.html

http://www.calix.se/consumer/index.asp?lang=UK

One more. II found a list of engine heaters for Hiace:

http://www.defa.com/finn_dok_h.php3?merke=...=2&lang=3&ndid=