Blocking the grille on diesel engines is common. Jetta diesel owner block theirs with good results. Since the Atkinson cycle engine is very efficient and takes time to warm up, blocking the grille should help to heat the engine sooner.
The heating of the batteries is interesting. Even if you get the engine temperature up, the batteries may require the engine to remain on until they are warmed up.
So the trick is to block the grille and drive it like you stole it.

 

Yes I guess, but geez, doesn't the ICE need to be maintained at a certain temp to reduce engine wear from running too hot? Bypassing the cooling solution seems like a bad idea to me.

My solution to getting reducing running of the ICE (but I don't live in Alaska either!) is just to run the seat heaters until the car has warmed up on its own. I live at 2000' and commute to 400': the car stays in EV mode until I hit 47mph, then halfway down the hill the engine has warmed up enough to provide hot air.

 

The engine won't overheat with the amount of air that gets to the radiator. Cooling systems are pretty efficient and there's enough air in the engine compartment to allow for cooling. There are also radiator cooling fans that will force air through the radiator if needed. I did this on my Jetta TDI with no issues.
I don't have the seat heaters, but I do try to rev the engine to get the batteries to charge faster.

 

This may be futile, as this is not normally how the car works.
Idle RPM provides enough power to charge the batteries, if they desire charging. The colder, the few amps allowed, and thus, even less engine power is needed. IMHO you are only wasting gas.

 

I'm interested to know what people are using to block the grille's. I refuse to tape a piece of cardboard to the front of it and don't want to use anything that will damage the finish.

 

I don't need to block my radiator here in Jupiter but I read an article about damage to the A/C compressor with limited airflow. Here it is with a link to the article:

"Another design concern, especially relating to a clutch cycling orifice tube (CCOT) system, is the high impact loads placed upon the compressor as it cycles on. Most compressors are driven faster than engine speeds (overdriven), due to a smaller diameter compressor pulley versus the crankshaft pulley. Engaging a compressor at engine speeds above 1500 rpm with high discharge (head) pressures places extreme loads upon the compressor's components. To add to this destructive process, most newer vehicle designs employ lower hood lines and little or no grill openings. As a result, compressor head pressures increase due to limited airflow over the condenser."
http://www.asashop.org/autoinc/march2003/mech.htm

This may or may not be a problem with a radiator block but something to consider.

GaryG

 

I think we're all talking about a block that covers the grille and not the radiator directly. The enclosure is not air tight and therefore if cooling were necessary the fans would be enough to cool the engine. Of course, we're also talking about this for cold climates only.

 

The Jetta used foam pipe insulation from HD. Depending on the location different sizes are needed to provide the right fit. You can also hang a piece of heavy plastic (1/8" or better) in front of the radiator using wire ties.