Home made supercharging?

[The Other Dan]

Is there anyway to "make" a DC supercharger? Specifically, I'm thinking can you rent a 250kw or greater generator for an event, and have it set up to do DC direct charging?
I understand the easy thing to do is use the mobile connector and do 14-50 AC charging, but it's way too slow.

Unless theres already a solution, I guess I see two obstacles to overcome. Getting the power to the car, and getting the Tesla to accept the energy.

Anyone have any ideas?

 

[E90alex]

If you can supply enough energy, you can probably buy a DCFC cabinet but they are tens of thousands of dollars.

You’re not going to be able to hack together a solution for cheap if that’s what you mean.

 

[LoudMusic]

250kw is a craptonne of power. Does Tesla even make mobile 250kw chargers? I know they make mobile 72kw chargers. And if your event is significant enough I bet you could get Tesla to involve themselves.

But just to wrap your head around it, a house with 200A service is only 48kw.

 

[srs5694]

Is there anyway to "make" a DC supercharger? Specifically, I'm thinking can you rent a 250kw or greater generator for an event, and have it set up to do DC direct charging?
I understand the easy thing to do is use the mobile connector and do 14-50 AC charging, but it's way too slow.

Unless theres already a solution, I guess I see two obstacles to overcome. Getting the power to the car, and getting the Tesla to accept the energy.

There are companies that sell low-power DC fast chargers -- in the 10 to 60 kW range. For instance, Setec sells such devices. (They made the first CCS1-to-Tesla adapter, which was limited to 50kW but worked with all Teslas except the Roadster -- even those without CCS protocol support.) I'm sure there are other manufacturers of such low-end DC fast chargers, but I don't have any references handy. Most such suppliers are probably able to fit CHAdeMO or CCS plugs. NACS plugs are new enough that they might be harder to find. (Setec claims to be able to supply them, but I have no idea if that's really true or if it's just something that's theoretically true that they've slapped on their Web page in the hopes of getting orders.)

If you really need something on the order of the 250 kW you mention, then your best bet is probably to buy a DC fast charger from one of the many reputable manufacturers of such devices. They'll be hugely expensive, of course, but I wouldn't trust a jury-rigged DC fast charger. Right now, you might need to get one with a CCS plug and use Tesla's adapter (which won't work with older Teslas); but in a few months you should be able to get one fitted with a native NACS plug (which probably won't work with older Teslas).

Your query doesn't seem to be theoretical; you seem to have a particular use case in mind. Sharing the details might help people offer better suggestions.

 

[The Other Dan]

250kw is a craptonne of power. Does Tesla even make mobile 250kw chargers? I know they make mobile 72kw chargers. And if your event is significant enough I bet you could get Tesla to involve themselves.

But just to wrap your head around it, a house with 200A service is only 48kw.

250kw is just a V3 supercharger. Not that big a deal.

In the commercial world, a 250kw generator isn't that big. You can rent them, they are built on trailers.

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A 250kW diesel generator provides ideal power solutions for temporary, standby and emergency power requirements. All models feature quiet operation (60 dBA or lower at full load) and onboard fuel capacity of 24-hour minimum run times. Multiple voltages are easily configured, simultaneous single...

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[The Other Dan]

Your query doesn't seem to be theoretical; you seem to have a particular use case in mind. Sharing the details might help people offer better suggestions.

Not theoretical at all. As far as use case, you don't need to look any further than the Gridlife Model 3 Challenge racing events. Or the SCCA Solo
National Championship.
Having on site fast charging would be a huge help. Getting the power to the track via a generator is relatively cheap. Getting it to the car is really the dilemma.

 

[srs5694]

Not theoretical at all. As far as use case, you don't need to look any further than the Gridlife Model 3 Challenge racing events. Or the SCCA Solo
National Championship.
Having on site fast charging would be a huge help. Getting the power to the track via a generator is relatively cheap. Getting it to the car is really the dilemma.

For a racing event, I think you really need to be talking directly to DC fast charging equipment manufacturers. I'd contact ABB, BTC, ChargePoint, FLO, Freewire, Kempower, SK Signet, Tritium, and of course Tesla itself, if you'll be charging Teslas. (I'm sure I've omitted some charging equipment manufacturers; these were simply the ones I noticed on a quick pass through the list of manufacturers who will be supporting NACS.) If I'm not mistaken, ABB sponsors and is providing the charging infrastructure for Formula E, so they already have expertise with this sort of thing. I'd be surprised if at least some other manufacturers wouldn't be interested in selling equipment for your niche use-case, too.

 

[RTPEV]

I was thinking the only practical application where you would need lots of power AND have low dwell times (as opposed to an event where most people are parked all day, like a music festival or something like that) would be a racing event.

You really don't want to "homebrew" a DC fast charger for >50kW charging. You want to actually buy one (or several). Obviously you won't be able to buy a Tesla Supercharger (although they do have mobile Superchargers mounted on flatbed trucks--I suppose you could inquire about renting one), but you can almost certainly buy a CCS unit (and perhaps NACS in the future). It'll cost you of course, but these are not toys mind you. And perhaps you can find one of the ones that Electrify America has recently ripped out, some without even ever being commissioned (see Cheyenne, WY Electrify America for example). You might be able to get a nice deal on them.

But speaking practically, the best solution is going to have the track install a set of permanent fast chargers. Many tracks are already doing this. So just host your event at a venue that is smart enough to see the value in having on-site charging. For example, it's been a year since the last post, but it looks like Tesla did install Superchargers at Laguna Seca (one of the Model 3 Challenge venues). I don't know if they are active yet though. Laguna Seca (Coming Soon) | Monterey, CA | EV Station

Edit: I did find the forum here on this site (strange that it didn't show up in my search) Supercharger - Laguna Seca Raceway, CA (LIVE Sep 2022, 8 V3 stalls, possibly restricted access) Definitely active at least for race participants

 

[jboy210]

...

But speaking practically, the best solution is going to have the track install a set of permanent fast chargers. Many tracks are already doing this. So just host your event at a venue that is smart enough to see the value in having on-site charging. For example, it's been a year since the last post, but it looks like Tesla did install Superchargers at Laguna Seca (one of the Model 3 Challenge venues). I don't know if they are active yet though. Laguna Seca (Coming Soon) | Monterey, CA | EV Station

Edit: I did find the forum here on this site (strange that it didn't show up in my search) Supercharger - Laguna Seca Raceway, CA (LIVE Sep 2022, 8 V3 stalls, possibly restricted access) Definitely active at least for race participants

Maybe @jjrandorin can help out on the restrictions. I think this is nearby.

 

[MP3Mike]

Like others have said your best bet is likely to buy a CCS charger, but that pretty much limits you to ~200kW for Teslas right now.

@wk057 might also be able to help with a Tesla compatible DC fast charger.

If it is just for an event, it might be possible to work with Tesla to rent one of their portable Supercharger trailers. (They have a Megapack and a bunch of Supercharger stalls on them, and can hook to the grid, or a generator, to top up the Megapack if you need a lot of charging.) There are other companies that make the same kind of thing but with CCS chargers, but I don't recall who off the top of my head.

 

[ucmndd]

250kw is just a V3 supercharger. Not that big a deal.

In the commercial world, a 250kw generator isn't that big. You can rent them, they are built on trailers.

250kW Diesel Generator Rental | Sunbelt Rentals

A 250kW diesel generator provides ideal power solutions for temporary, standby and emergency power requirements. All models feature quiet operation (60 dBA or lower at full load) and onboard fuel capacity of 24-hour minimum run times. Multiple voltages are easily configured, simultaneous single...

www.sunbeltrentals.com

The problem you’re going to have with a generator is that anything readily available that produces the level of power you’re talking about is going to output AC. So now you’ve got to rectify to DC.

Then you need signaling equipment that can speak CCS or NACS and negotiate a session with the car.

At that point you’ve just rebuilt a DC fast charging cabinet, likely for more cost, more complication, and less reliability than something available off the shelf.

 

[wk057]

I've had a homebrew supercharger built for a while (120kW max currently), but it's not something quite ready as a product I could sell.

 

[The Other Dan]

The problem you’re going to have with a generator is that anything readily available that produces the level of power you’re talking about is going to output AC. So now you’ve got to rectify to DC.

Then you need signaling equipment that can speak CCS or NACS and negotiate a session with the car.

At that point you’ve just rebuilt a DC fast charging cabinet, likely for more cost, more complication, and less reliability than something available off the shelf.

Thank you. This was some of the details I was looking for to see if it was doable.

 

[ucmndd]

Thank you. This was some of the details I was looking for to see if it was doable.

I think there are really two parts to your question - generation and distribution.

For power generation I see no reason why a big diesel generator like you’re proposing wouldn’t work. For distribution connect it up to a commercial DCFC solution mounted on a trailer or something.

 

[pipestem]

First @wk057 that is very impressive. I take it the model S rehab business is going well.

Second, I have to wonder why someone needs this. It's like saying you need to drive 250 miles, come home, charge, drive another 250 miles and come home in one day. Otherwise it seems like regular overnight 14-50 charging is enough.

EDIT: Ok, maybe if you are charging a fleet of vehicles....

 

[wk057]

"Need" is a strong word.

 

[Whatstreet]

DC chargers use multi-phase boost circuits to increase the DC voltage from the 440V line voltage. Not trivial but the circuitry does exist and eliminates transformers but does use an array of small inductors (lots of them).