Frozen Car + Block & Electrical Heating = Unfrozen

When its really cold outside & your car is frozen & you are not in a big hurry to leave, you can use an electric space heater & an engine block heater to preheat your vehicle. 

Preheating a car with 1 kilowatt electrical energy takes hours. In this example, I have a small 700 watt oil filled electric space heater sitting on top of the center console (image, blurry, through frozen ice covered window I wiped off with my hand) plugged into a 50 foot extension cord. The 50 foot  cord was put through the drivers door window & window close to barely hold the cable, then routed to the front. (next image) 

700w space heater on top of the center console

700w space heat extension cord out the window

An outlet splitter was used combine the engine block heater cord & extension cord so that I could plug this 2 cord input into the output of a 12 foot extension cord plugged into the GFI outdoor 120vac NEMA 15-R socket capable of serving up 1875 watts total continually before the breaker in the electrical panel would turn off the energy flow. Last Image

Cord splitter combines 2 cables into 1

Black extension cord plugged into power outlet
"white one for LED Holiday Lights"

Engine block heating from frozen to 105 deg F or about 41 deg C, before starting the engine, greatly enhances the life of the engine by reducing the viscosity of the oil which can flow into the engine more easily when lightly warmed vs frozen cold & thicker. This reduces startup wear on the piston rings, cylinder walls, crank bearings, overhead valve trains & other moving parts lubricated by oil in the engine. I got the idea of preheating with a block heater from my Dad who had been working in Northern Canada back in the 1960's where block heating vehicles very common due to the ultra low outdoor winter temperatures well below freezing. Later, when learning about F1 car engines, I learned that they preheat to over 154 deg. F before startup because the tight tolerances in the engine make it very hard to start or nearly impossible to start at room temperature. Heating causes the metals to expand which creates more space between high friction points that allows a thin film of lubricating oil to get in there to reduce wear & improve operating life of the engine. 

This setup uses about 1kw of electrical energy or costs about $0.12 USD2022 / hour to operate & takes about 3.5 hours ~$0.50 to warm from sub-freezing in the upper 20's as depicted in the title image digital thermometer display of 28.8, to a pleasant cabin temperature in the upper 60's & engine block around ~105 deg. F. Warming saves more than $0.50 worth of gasoline in this 46MPH Prius, which can  inhale 32 oz or about 1 liter of gasoline during a cold start rich fuel mix warmup sequence if the engine frozen cold. By starting it above room temperature, it enters a lean burn fuel saving mode called S4 faster. The Prius II has 5 operating modes. S1-3 are cold start procedures, S4 happens around 146 F & full S5 operation happens when the engine reaches 176 F on its way to 186 F the full operating temperature under continual driving road trip conditions. 

You do not have to live in a house or have a garage to do this. You just need to be parked with a practical distance to an electrical outlet. Electric Cars like a Nissan LEAF can be charged this way too, just make sure to use 12-3 or 10-3 cables & 50 feet or 100 feet a practical limit. Level 1 extension cord charging an electric car adds about 5 miles of battery range per hour of charging.