Thanks for sharing that!
See thread: Use your Micra's block heater: save fuel, reduce wear, be more comfortable.
Block heaters are a bit of a hassle to use regularly, but they're worth using:
- better fuel economy
- good for the battery
- better engine longevity
- you get cabin heat sooner when it's cold outside
You shouldn't need to plug in for more than about 2 hours -- any more than that and you're just heating up the air around the engine through heat loss.
You could use a timer to set it to come on at the appropriate time if you're on a regular schedule.
I even got a remote controlled outlet for mine so I could switch it on from inside the house (I don't drive on a schedule).
View my fuel log 2015 Micra S manual: 5.0 L/100 km ... 56.5 mpg (Imp) ... 20.0 km/L ... 47.0 mpg (US) ...