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Discussion Starter · #1 ·
Was bemused the other day by a fellow Gen 1 E-Golf owner saying they regularly got 90+ miles out of their 24kwh E-Golf.

At a stretch mine has always struggled to get 60-70 miles.

However, after a service the garage left the fans off & my range suddenly said 99 as I was driving back home. Due to cold weather didn't put them back on and noticed a huge range improvement. Today, a journey that would usually take a third of the electricity has taken less than half of the electricity (just a small blip on the needle). I'm suddenly seeing massive range improvements by turning the fan off!

I always knew he AC compressor had a big impact on range, but assumed just running normal fans without AC wouldn't impact range, but apparently does massively.

Anyone else experienced this & is to be expected?

Thanks.
 

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Cabin heating uses a lot of energy, especially if your car is not equipped with a heat pump. Turning on the “fan” also engages heating, and thus you get less driving range. If I turn off the fan (HVAC off) I get much more range, especially on a cold day. I love the seat heater because it warms my back as well and it only drops range by 1 mile. I wish the steering wheel had heat.
 

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Discussion Starter · #4 ·
Does "turning fans off" mean turning the whole climate system off, and thus not using the cabin heater?
Yep as in turning the entire HVAC off, so no air being circulated into the car at all.

I have heated seats which only take 1 mile of range (miss my Leaf's heated steering wheel).

Recall reading somewhere the reason the temp defaults to 22 is to ensure minimal battery usage. Presumably this is the optimal temp for not draining the battery & working the system hard. However, even this seems to have a big hit on range.
 

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Let's do a little man maths...
  • 90 miles from 24kWh = 266W/mile
  • Randomly googling around, the blower motor in a Jetta consumes between 3.8A and 19.8A: Blower motor draw
  • Assuming it's 12V, that's 45.6W to 237.6W.
  • With the fan running, your consumption is now between 311W/mile and 504W/mile.
  • With a 24kWh battery, that's a range of 47.9 miles to 77.2 miles.
So yeah, seems reasonable.
 

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Good analysis but some units are off. Only about 21.5 kWh is usable (when new). Also, 266 Wh (Wh not W) is a bit of a rough average. Could be as low as 200 Wh/mile or as high as 350 Wh/mile, depending on how you drive. Assuming 266 Wh/mile average efficiency, if the fan uses 235 W, and is running for an hour, that means it consumes 235 Wh but the per mile usage depends on how fast you drive. If you average 50 mph, then the fan adds 4.5 Wh/mile. The fan itself is a small energy use compared to the PTC heater, which is rated at 5000 W.
 

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Good analysis but some units are off. Only about 21.5 kWh is usable (when new). Also, 266 Wh (Wh not W) is a bit of a rough average. Could be as low as 200 Wh/mile or as high as 350 Wh/mile, depending on how you drive. Assuming 266 Wh/mile average efficiency, if the fan uses 235 W, and is running for an hour, that means it consumes 235 Wh but the per mile usage depends on how fast you drive. If you average 50 mph, then the fan adds 4.5 Wh/mile. The fan itself is a small energy use compared to the PTC heater, which is rated at 5000 W.
Yup, man maths ;)
 

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So when the fan is on, the heat is running, even if the a/c is switched off? Even when the thermostat is set to a temp that would not trigger heating? I’ve suspected this and have occasionally wondered if there’s a way to run ONLY the fan (get some fresh air from outside). Seems that scenario is a crazy unattainable fantasy?

Sometimes for reasons like this I miss my 1987 Golf.
 

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Yes, there is no independent way to turn off the heater other than by temperature setpoint. You can go to one of the efficiency screens and see how many miles (or km) range is being reduced so you could play with the temp dial to minimize that number.
 

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There's a button that can enable/disable air circulation. If you disable it, you actually allow outside air to comes in and even though you have the climate control off, you can feel a breeze from the AC port (depending on your speed)

So when the fan is on, the heat is running, even if the a/c is switched off? Even when the thermostat is set to a temp that would not trigger heating? I’ve suspected this and have occasionally wondered if there’s a way to run ONLY the fan (get some fresh air from outside). Seems that scenario is a crazy unattainable fantasy?

Sometimes for reasons like this I miss my 1987 Golf.
 

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I drove to half way to work this morning with the temp on low, and aircon off and the fan on one or two.

Looking at the gom figures and how cold the car was there's no heating going on.

After a while I started playing with the temperature settings and it affected the gom reading straight away, and I warmed up!
 

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Woodulike, thank you for confirming the HVAC fan uses very little energy and that the heater is what significantly reduces range. If someone wants fresh air but no heat, bring a few blankets and dress warmly for your long drive.
 

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When a car’s defrost mode is selected, the A.C. Is automatically engaged even when it is deselected or if heat is selected (you get heat and ac at the same time going to the windshield). This has been standard (at least in U.S. vehicles) for many years. The a.c. dehumidifies the air, thus aiding the clearing the inside of the windshield. Maybe try fan mode and be sure it is only passenger directed and not windshield directed to save energy.
 
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