short heat pump test

[tvwe]

In the past few days i have borrowed my friend's egolf2019. it has a heat pump version. I was wondering how much more economical it would be to drive. I drive a route to work of about 49 km, average speed is aroung 56 km/h. Of course, this is not the length of the route for some fundamental conclusions, but since I ride in the morning at 5 am, there are free roads, so I can ride the route almost identically, with the same speeds on individual parts of the route and the same overall avg speed limit. That's what I was advised to do. The temperature on one day when I rode my egolf2018 was -0.5C (SOC at start 79.5%, temperature of individual batteries according to obd11 min 1.5C, max 6.5C), the temperature when riding with egolf2019 (heat pump) was 0.0 C (SOC at start 84.5%, temperature of individual batteries according to obd11 min 1C, max 5 C). Before the start, both golfs were heated up and charged using the timer (there is little bit difference in SOC). The heating during the drive was set the same, at 22 C, the same air conditioning blower setting. I drove alone in car. That was the initial conditions.
Consumption read from OBD11, for the route for egolf2018 was 6,300 kwh, which means 12,85 kwh/100 km, for egolf2019 (heat pump) was 6,000 kwh, which means 12,24 kwh/100 km. That's only a 5% difference, which is less than I expected. Heating was pleasant for both. I was wearing a thin sweatshirt only.

For the egolf2019, there is a slight hum of the heat pump. It's not a big noise, you only notice it when you have an egolf without a heat pump.

What are your experiences? with egolf with/out heatpump?

I expect, that with lower temperature difference will be even lower, how COP of heatpump go down.

T

 

[f1geek]

Need to repeat test a few more times. Was tire pressure the same? Same wear on tires? Same wind conditions? Same car mode (normal, Eco, Eco+)? A longer drive may help, too.

I would expect more like 30%. I suspect without pre-heating cars you will see much bigger difference.

 

[tvwe]

Pressure of tire should be the same. I am not sure about how old tires were at my friend egolf2019, but my are new this winter. And my type isnt for low consumption, i was select with good behaviour on ice...
Drive mode was the same.
Probably without preheating should be different... But, when i look to my wallbox data to consumption of preheating, there is not to much difference. With heat pump it consumed 0,9 kwh, my golf witout consumed 1,2 kwh. If we take that this preheating was 1/2 hour, the difference is 0,6 kwh per whole hour of heating. I am driving to work less then hour, consumption is around 13 kwh/100 km. So 600 wh at 13kwh is close to my 5%.
Because i am now before building het pump for my house, i dont understand why so small difference is, id should be really much bigger. especially when i know how big COP heat pump have around 0 C. But this is what i measured.

 

[f1geek]

33% less energy to preheat using heat pump, as I would expect.