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[oldgeeksguide]

I’m changing up the bed configuration of the Lightning. Going from a tonneau cover to a cap. We get more space and more solar panel mounting space, so it’s win-win-win.

To do that, I decided to wash the bed after removing the tonneau cover. But I wanted to use the pressure washer and the hose location is too far from an outlet in the workshop and I didn’t want to run an extension cord. Fortunately the truck has plenty of electric power to run a pressure washer.

View attachment 9109

I’m picturing plugging it into an outlet in the bed while washing the bed and wondering what happens when you point it at the outlet

 

[Chavannigans]

I had taken the statement to mean that they thought that the biggest impact was wiper motors, not the biggest impact is rain. While the latter often necessitates the former, the wiper motors can be on without there being any rain—I knew a kid in high school who always drove with the wiper motors on. Very bizarre.

I discount the energy costs of wiper motor, headlights, etc. With modern vehicles, those are minimally impactful. I can even go out to measure it in the truck if needed.

Rain in the air impact on aerodynamics has only a couple percent impact on automobile drag (so overall not a large percent on total range). Though we get soaked during a rainstorm, the relative density of the air doesn’t change a lot, and the mass of the rain only matters a little bit.

However, as you noted: a thin film of water on the road will absolutely increase rolling resistance. It will depend a bit on the tire tread. Here’s one example from a research paper where they did experiments on the roads in Poland and Sweden.

You can see that for an 80 kph test, at about 0.65-0.7 mm of rain on the road surface, the rolling resistance is increased by about 40%. It gets even higher at higher speeds. This is in part due to the vehicle pushing water as you mentioned. It’s also because the tire temperature is decreased and that causes lower pressure and thus increased rolling resistance. This is just rolling resistance. This impact will be more noticeable at low speeds since rolling resistance has a greater relative effect on efficiency at low speeds. At higher speeds, drag takes over.

View attachment 9096

Humidity doesn’t have a large impact on aerodynamic drag; this is mostly because high humidity air tends to be warmer air and density is more dependent on temperature than humidity, so highly humid air tends to be less dense.

Overall, for an EV, on a no-HVAC drive, something like >95% of the energy gets to the driveline (as opposed to ICEs, which lose about 79% of the energy to heating up the surroundings without producing useful work). Driveline losses cost about 2% - 5%. So about 90% of the energy is delivered to the wheels.

On the highway, about 45%-50% of the total energy expenditure is spent on pushing the air out of the way. If there’s a 4% increase in aerodynamic drag due to rain, that’s a 2% increase in total energy expenditure. 350 miles * 0.02 = 7 miles reduction in range.

For rolling resistance, at highway speeds, about 15% of the total energy expended is due to rolling resistance. If that increases by 50%, that’s another 7%-8% increase in total energy expense, which is about 28 miles reduction in range assuming 350 miles range.


Reducing speed a bit will overcome most or all of that increase in resistance.

Thank you for being thorough and taking the time to demystify things as you do.

I was pretty skeptical about the claim but the most surprising part of your insight to me was the tire pressure being lowered by the heat transfer with the water.

I’m sure we have all had the pleasure of a tire pressure warning light greeting us on a frigid winter morning, and witnessed it disappear after a few minutes of driving.

Does the study flesh out the temperature delta as well as well as the pressure variance?

Trucks and SUVs tend to run higher pressures so it makes me wonder if they will experience the same impact as a sedan.

Electric vehicles tend to be even heavier so I imagine factory recommended pressures for Scouts will be higher than their ICE counterparts.

So would it cause as much of an impact for the larger and heavier vehicles?

 

[SpaceEVDriver]

I’m picturing plugging it into an outlet in the bed while washing the bed and wondering what happens when you point it at the outlet

Plugged it into the frunk for just that reason.

 

[SpaceEVDriver]

Thank you for being thorough and taking the time to demystify things as you do.

I was pretty skeptical about the claim but the most surprising part of your insight to me was the tire pressure being lowered by the heat transfer with the water.

I’m sure we have all had the pleasure of a tire pressure warning light greeting us on a frigid winter morning, and witnessed it disappear after a few minutes of driving.

Does the study flesh out the temperature delta as well as well as the pressure variance?

Trucks and SUVs tend to run higher pressures so it makes me wonder if they will experience the same impact as a sedan.

Electric vehicles tend to be even heavier so I imagine factory recommended pressures for Scouts will be higher than their ICE counterparts.

So would it cause as much of an impact for the larger and heavier vehicles?

I'll have to dig into the papers when I can see straight. To better understand the specifics of temperature changes, I will need to find several more papers too. I imagine it will depend a lot on tire construction, composition, mass, size, and temperature before encountering the water. A low profile street tire may be affected more than a large AT tire, for example. A hot tire will lose more energy than a cooler tire, and so will lose more pressure. I'll have to read up.

The recommended pressure for the Lightning is 36 PSI for AT and 42 for AS tires. For the ICE trucks, it's 35, 40 for the F-150 HD package, and 38 for the Raptor off-road tires. I run the Lightning at 48-50 on the ATs. It's a harsher ride, but the handling is far superior. I imagine the impact of water-cooling will not be much different between the two power plants.

 

[dreamweaver]

Plugged it into the frunk for just that reason.

I haven't been able to find a definitive answer for this question. Are EV electrical outlets GFCI and/or AFCI protected?

 

[6-ScoutFamily]

Manly men don’t need no stinkin’ GFCI!

 

[SpaceEVDriver]

I haven't been able to find a definitive answer for this question. Are EV electrical outlets GFCI and/or AFCI protected?

The Lightning has GFCI on its 120 V outlets. No AFCI as far as I know.

 

[SpaceEVDriver]

Manly men don’t need no stinkin’ GFCI!

Like the fools of old who tested whether circuits were live with wet fingers...

 

[J Alynn]

Plugged it into the frunk for just that reason.

Nothing slips by you

 

[Warbirds]

Very interesting.

Is it impossible to do a burnout? What happens if you disable traction control?

(Please dont break your truck for science I am just curious)

The braking on an EV also routes through the electric motor This is at a high level how battery regeneration works as well, it transfers that braking energy through the drive system. So the good news is your brakes can last a really long time.
I haven’t seen an EV that will “power brake” like a RWD car.

The driving experience of my Audi E Tron own I would compare to any of the modern AWD ice cars, like a Subaru STI.

If I put it it “dynamic” mode and shut off the traction control it behave just like any hooligan AWD ICE car.

It can absolutely do donuts in snow which is quite entertaining.

 

[SpaceEVDriver]

Thank you for being thorough and taking the time to demystify things as you do.

I was pretty skeptical about the claim but the most surprising part of your insight to me was the tire pressure being lowered by the heat transfer with the water.

I’m sure we have all had the pleasure of a tire pressure warning light greeting us on a frigid winter morning, and witnessed it disappear after a few minutes of driving.

Does the study flesh out the temperature delta as well as well as the pressure variance?

Trucks and SUVs tend to run higher pressures so it makes me wonder if they will experience the same impact as a sedan.

Electric vehicles tend to be even heavier so I imagine factory recommended pressures for Scouts will be higher than their ICE counterparts.

So would it cause as much of an impact for the larger and heavier vehicles?

Okay.

Here’s the data that I gathered, and it makes sense to me from other studies I’ve read regarding temperatures and rolling resistance—just wanted to be sure the wet didn’t have some other kind of impact. Internal flexing and internal friction of the tire accounts for about 85-95% of rolling resistance, much of which is controlled by pressure and temperature of the tire.

For every 10 degrees F (5.6 degrees C) change in air temperature, tire pressure changes by about 2%. This should be about the same relationship for the internal temperature of the tire as well, which will change more dramatically while you’re driving than the ambient air temperature. For the table below, a 7 degree C change would suggest about 2.5% change in pressure, or about 1 PSI change. So, not a lot.

Typically a change in tire temperature of 1 degree C will change the tire’s rolling resistance by about 1-2%. This is born out in this test as well. They didn’t test any “US truck” tires, so those don’t show up here, but the results will be similar until tires are designed very differently from these.

Note also that internal friction (tire temperature) probably has a greater impact on rolling resistance at low vehicle speeds compared with high vehicle speeds.

For this one article, they tested four tires. The numbers are approximate, but close enough.

Brand / designation	Size	Type	Note 1	Starting Pressure (no indication of measured pressure during the test)	Temperature Change (degrees C)	Rolling Resistance Change due to temperature
Avon AV4 AAV4D	195R14C	M&S Commercial-grade Steel-belted Radial; SuperVan AV4	Reference tire for acoustics analysis “H1”. Approximately the same size as 205/75R14	210 kPa (30.5 PSI)	7	7%
Uniroyal Tiger Paw SRTTD	P225/60R16	AS Steel-belted radial for large passenger cars and vans.	Reference tire for acoustics analysis “P1”.	210 kPa (30.5 PSI)	10	10%
Michelin Primacy HP MCPRD	225/60R16	Consumer-available touring / summer tire.	Market tire	210 kPa (30.5 PSI)	8	8%
Pirelli P1 Verde VTICD	195/60R15	Consumer-available touring/summer tire	Market tire	240 kPa (34.8 PSI)	4	8%

 

[Logan]

I’m changing up the bed configuration of the Lightning. Going from a tonneau cover to a cap. We get more space and more solar panel mounting space, so it’s win-win-win.

To do that, I decided to wash the bed after removing the tonneau cover. But I wanted to use the pressure washer and the hose location is too far from an outlet in the workshop and I didn’t want to run an extension cord. Fortunately the truck has plenty of electric power to run a pressure washer.

View attachment 9109

Yesterday I got the V2L adapter for my Ioniq 9 in the mail, as well as the floormats.

So I tried out the V2L adapter, by using it to power the shop vac to vacuum the car .

Worked great. Its not huge power (120v 15amps only), but I'm super excited to use this for powering the house during power outages this winter, as 1800w is enough to run basically everything in the house other than heating. So instead of waiting confirmation that the power outage will be > 4hrs before I drag out the generator, I'll just plug in the V2L adapter, drag an extension cord under the garage, plug in my Nema 5-15 - LR14-30 adapter into the manual transfer switch, and run things until morning.

If its a long power outage, that will be in the cold, we may still pull out the generator, as the generator has enough power to handle a space heater or two (its a small ~3500w generator). But otherwise, we'll likely just pull power from the Ioniq during outages.

 

[SpaceEVDriver]

Yesterday I got the V2L adapter for my Ioniq 9 in the mail, as well as the floormats.

So I tried out the V2L adapter, by using it to power the shop vac to vacuum the car .

Worked great. Its not huge power (120v 15amps only), but I'm super excited to use this for powering the house during power outages this winter, as 1800w is enough to run basically everything in the house other than heating. So instead of waiting confirmation that the power outage will be > 4hrs before I drag out the generator, I'll just plug in the V2L adapter, drag an extension cord under the garage, plug in my Nema 5-15 - LR14-30 adapter into the manual transfer switch, and run things until morning.

If its a long power outage, that will be in the cold, we may still pull out the generator, as the generator has enough power to handle a space heater or two (its a small ~3500w generator). But otherwise, we'll likely just pull power from the Ioniq during outages.

I never installed a V2H connection. I just use a pile of extension cords. With the 240 V, 30 A inverter (7.2 kVA or 7.2 kW) and the separate 120 volt, 20 A
(2.4 kVA or 2.4 kW) inverter, I can power pretty much everything I need to power. Including a radiative heater. The Lightning’s power output was one of the selling points for me.

 

[Logan]

I never installed a V2H connection. I just use a pile of extension cords. With the 240 V, 30 A inverter (7.2 kVA or 7.2 kW) and the separate 120 volt, 40 amp (2x20 A) (2.4 kVA or 2.4 kW) inverter, I can power pretty much everything I need to power. Including a radiative heater. The Lightning’s power output was one of the selling points for me.

Yeah, thats how I plan to do it with the Scout, assuming they stick with what they've said.

And agreed, the power output of the EV trucks is quite appealing.

With my Ioniq 9, I don't have the option to output anywhere near the kind of power you can get from the Lightning (although I wish I did). The next best thing was just an adapter that plugs into the charging port, and lets you draw from the battery.

Its not tons of power, but it should be enough to run the fridge/freezer/basics during an outage.

 

[SpaceEVDriver]

Yeah, thats how I plan to do it with the Scout, assuming they stick with what they've said.

And agreed, the power output of the EV trucks is quite appealing.

With my Ioniq 9, I don't have the option to output anywhere near the kind of power you can get from the Lightning (although I wish I did). The next best thing was just an adapter that plugs into the charging port, and lets you draw from the battery.

Its not tons of power, but it should be enough to run the fridge/freezer/basics during an outage.

I see my arithmetic was wrong---embarrassingly wrong---I fixed it in my post, but it's preserved in your reply.

I hope Scout offers 7.2 kW-9.6 kW of power in the form of a 240v outlet. In both the Terra and the Traveler.

 

[Chavannigans]

EV owners, does the power ever get boring?

Do you use all of the pedal when you’re merging?

Do you still do hard launches with other people?

Do you ever find yourself driving more aggressively or assertively?

 

[strider]

EV owners, does the power ever get boring?

Do you use all of the pedal when you’re merging?

Do you still do hard launches with other people?

Do you ever find yourself driving more aggressively or assertively?

You will get used to the power but it never gets boring.

I use as much pedal as I need when merging. But what I have noticed is that with this much power I need WAY less space to do the merge so that is helpful. Same thing with merging into traffic during a left turn. You don't need much of an opening as you can accelerate to traffic speed very quickly. In a related way, on a 2-lane you can execute a pass in a remarkably short distance.

I will launch it whenever someone asks. 2.5 to 60 feels like warping space and time.

My EV transition was from a C6 Corvette to a Tesla Roadster. Other than the above, being able to stick myself into smaller openings, I did not change my driving style. Driving an EV is so freeing because you don' t have a stupid transmission to manage (it was especially acute for me as my Corvette was a 6-speed manual). Also, I find that I engage in less aggressive driving - there is an aspect of "walk softly and carry a big stick." When someone is trying to show off or challenge me I just let them go because I know I could destroy them. It would just be embarrassing for them. Of course now that I'm in my 50s, maybe I've just mellowed out

 

[strider]

I see my arithmetic was wrong---embarrassingly wrong---I fixed it in my post, but it's preserved in your reply.

I hope Scout offers 7.2 kW-9.6 kW of power in the form of a 240v outlet. In both the Terra and the Traveler.

I REALLY hope they put a 240/30 plug in the Traveler like they have in the Terra. That would be awesome.

 

[J Alynn]

EV owners, does the power ever get boring?

Do you use all of the pedal when you’re merging?

Do you still do hard launches with other people?

Do you ever find yourself driving more aggressively or assertively?

FA FO-

 

[J Alynn]

You will get used to the power but it never gets boring.

I use as much pedal as I need when merging. But what I have noticed is that with this much power I need WAY less space to do the merge so that is helpful. Same thing with merging into traffic during a left turn. You don't need much of an opening as you can accelerate to traffic speed very quickly. In a related way, on a 2-lane you can execute a pass in a remarkably short distance.

I will launch it whenever someone asks. 2.5 to 60 feels like warping space and time.

My EV transition was from a C6 Corvette to a Tesla Roadster. Other than the above, being able to stick myself into smaller openings, I did not change my driving style. Driving an EV is so freeing because you don' t have a stupid transmission to manage (it was especially acute for me as my Corvette was a 6-speed manual). Also, I find that I engage in less aggressive driving - there is an aspect of "walk softly and carry a big stick." When someone is trying to show off or challenge me I just let them go because I know I could destroy them. It would just be embarrassing for them. Of course now that I'm in my 50s, maybe I've just mellowed out

Just posted same mindset on another thread. Maybe 50’s are when we start to mellow out driving