Charging electric car

joebedford wrote:
Ida thunk that with regenerative braking, the EV could charge itself as you drag it down the road. Hey maybe I'll patent that idea.

I don't think you want to have your towed vehicle create any extra resistance. You will just have to supply more energy to keep the rig moving.

JRscooby wrote:

Reisender wrote:


You know that’s something you actually don’t think about but it’s true. We have had our pusher for almost 17 years. It has the original brakes and they have never been touched or adjusted. We have a little over 150 k on the clock. The plan was to run it till it’s 25 years old. Who knows, maybe I’ll still be on the same brakes.

I hope you or somebody that knows what they are doing check/lube the slack adjusters and S cams regularly. And 17 years is a long time for the rubber pancakes to last. On a truck, if you got the tools not a big job to change, but often let go when not handy. On the release side that wheel will not roll. Enough leak, and none of parking brakes will release. MH is hard to get under...

Yah. We get an annual maintenance and checkover done. Grease job. Filters, oil if needed. She’s been a good coach. One radiator and one exhaust manifold. Our mechanic is pretty good. I think he secretly wants to buy it when we are done with it.

Slack adjuster adjustment is part of our exam for an air ticket. I’ve done it but generally let him do it.

Reisender wrote:


You know that’s something you actually don’t think about but it’s true. We have had our pusher for almost 17 years. It has the original brakes and they have never been touched or adjusted. We have a little over 150 k on the clock. The plan was to run it till it’s 25 years old. Who knows, maybe I’ll still be on the same brakes.

I hope you or somebody that knows what they are doing check/lube the slack adjusters and S cams regularly. And 17 years is a long time for the rubber pancakes to last. On a truck, if you got the tools not a big job to change, but often let go when not handy. On the release side that wheel will not roll. Enough leak, and none of parking brakes will release. MH is hard to get under...

joebedford wrote:
I wasn't going to create energy out of thin air. I could be wrong but I thought that regenerative braking uses the motors as generators thereby causing drag which slows the vehicle. I wasn't suggesting engaging traditional brakes (I assume EVs have those in addition to regenerative brakes).

Yes, they have to have traditional brakes as well. Regenerative brakes only work when the wheels are turning. When the wheels stop turning, those regenerative brakes also cease offering any resistance to further turning. So while you can get almost entirely to a stop, you need traditional brakes to keep from rolling away (albeit at low speed) from a stop.

westernrvparkowner wrote:

joebedford wrote:
I wasn't going to create energy out of thin air. I could be wrong but I thought that regenerative braking uses the motors as generators thereby causing drag which slows the vehicle. I wasn't suggesting engaging traditional brakes (I assume EVs have those in addition to regenerative brakes).

If you are talking about outfitting Motorhomes with regenerative brakes to then charge a towed EV, that would require a massive regenerative system to effectively slow and stop a 40,000LB motorhome only for the benefit of a towed Prius. My personal driving experience with motorhomes is I seldom brake. Unlike driving a car, my motorhome is driven almost exclusively on trips. I go several hours at a time without even tapping the brake. I would think the average motorhome trip would provide very little in regenerative charging to the towed.

You know that’s something you actually don’t think about but it’s true. We have had our pusher for almost 17 years. It has the original brakes and they have never been touched or adjusted. We have a little over 150 k on the clock. The plan was to run it till it’s 25 years old. Who knows, maybe I’ll still be on the same brakes.

joebedford wrote:
I wasn't going to create energy out of thin air. I could be wrong but I thought that regenerative braking uses the motors as generators thereby causing drag which slows the vehicle. I wasn't suggesting engaging traditional brakes (I assume EVs have those in addition to regenerative brakes).

If you are talking about outfitting Motorhomes with regenerative brakes to then charge a towed EV, that would require a massive regenerative system to effectively slow and stop a 40,000LB motorhome only for the benefit of a towed Prius. My personal driving experience with motorhomes is I seldom brake. Unlike driving a car, my motorhome is driven almost exclusively on trips. I go several hours at a time without even tapping the brake. I would think the average motorhome trip would provide very little in regenerative charging to the towed.

Since EV’s are on the rise (thanks only to the invention of the high density Lithium battery), and knowing that Lithium is a limited non-renewable resource, besides wishful thinking, I wonder where this trend will eventually lead??

JRscooby wrote:

westernrvparkowner wrote:

joebedford wrote:
Ida thunk that with regenerative braking, the EV could charge itself as you drag it down the road. Hey maybe I'll patent that idea.

There is that pesky problem of physics. You cannot create energy out of thin air. On top of that, no system is 100% efficient. It will take more energy to drag that EV with it's brakes engaged than will be stored in the batteries.

True. OTOH, I think most toads use the normal braking system with control from the MH. If part of that braking system is regen, why not charge while slowing down? Then think about how many start their ICE before going out to car? Could the same system be used to turn on the motor, let the toad pull itself on uphills, or acceleration ramps? Or even push to limit of traction to help motorhome hold speed on hill? On normal cruise let it shut off, only turn on as you approach WOT.

As for charging at the RV Park. We do not, and will not, ever allow it. It isn't about the money. I don't think there is an RV'er that hasn't experienced a park where the voltage drops on a hot day when the park is full. EV charging draws significant amperage for long periods of time. RV park electrical systems are not designed to be able to handle the additional demands of charging EVs. As that voltage drop indicates, many parks are almost unable to handle the current demand without adding EV charging.

Your business, you can run it your way. But most hotel/motel are doing or thinking about doing it. As more E vehicles replace ICE, the calculation might change. Might work out better to have a small lot of charging stations where people pay separate fee for power from a separate line. Be better than the ones you know will run the MH on batteries while you sleep so can plug their car in.

Hotels and motels are generally in metro areas where power is more readily available. Also, hotels and motels do not need to offer the charging directly outside each room.
In an RV park setting there is tremendous pushback by guests against parking a vehicle anywhere but at their site. As for just feeding the charging area with a different line, I guess I wasn't clear in stating that in many rural areas (where RV parks are common) the power provider cannot just give the park more power. Their transmission system cannot provide the additional services. I don't doubt that somewhere in the future currently configured RV parks will become a thing of the past. (maybe it will be EV motorhomes, maybe it will be flying RVs and parks will need runways who really knows). But I believe that retrofitting current parks to be able to provide charging for EVs when the majority of the cars, trucks and RVs are actually Electrically powered will not be undertaken by many of those park owners. They will, instead, choose to sell and allow that land to be converted to other uses.

westernrvparkowner wrote:

joebedford wrote:
Ida thunk that with regenerative braking, the EV could charge itself as you drag it down the road. Hey maybe I'll patent that idea.

There is that pesky problem of physics. You cannot create energy out of thin air. On top of that, no system is 100% efficient. It will take more energy to drag that EV with it's brakes engaged than will be stored in the batteries.

True. OTOH, I think most toads use the normal braking system with control from the MH. If part of that braking system is regen, why not charge while slowing down? Then think about how many start their ICE before going out to car? Could the same system be used to turn on the motor, let the toad pull itself on uphills, or acceleration ramps? Or even push to limit of traction to help motorhome hold speed on hill? On normal cruise let it shut off, only turn on as you approach WOT.

As for charging at the RV Park. We do not, and will not, ever allow it. It isn't about the money. I don't think there is an RV'er that hasn't experienced a park where the voltage drops on a hot day when the park is full. EV charging draws significant amperage for long periods of time. RV park electrical systems are not designed to be able to handle the additional demands of charging EVs. As that voltage drop indicates, many parks are almost unable to handle the current demand without adding EV charging.

Your business, you can run it your way. But most hotel/motel are doing or thinking about doing it. As more E vehicles replace ICE, the calculation might change. Might work out better to have a small lot of charging stations where people pay separate fee for power from a separate line. Be better than the ones you know will run the MH on batteries while you sleep so can plug their car in.

We saw a Testa X towing a 20' Airstream trailer(US plates) parked in a campground in Newfoundland in the fall and of coarse the car was re-charging. Tesla just showed their full sized EV pick up truck(500 mile range) last week and other manufactures are to soon follow. Campgrounds will see more EV's in the future that are the tow vehicles and not just the toad. As mentioned, these charge using 240volts/48 amps. That may not be much more power being used than a RV with 2 AC's running plus other equipment. Example our AC/heat pump 30amps, water heater 12 amps,
Kuerig 15 amps, Microwave 12 amps, etc.