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The possibly impossible economics of DCFC

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The Burns charger is owned by the electric co-op so it is not subject to demand charges however competing stations like the Tesla Supercharger will be. The co-op servicing McDermitt does not have demand charges for large commercial. Many rural stations that are being built are using a combination of government grants, EV specific negotiated power rate plans, utilities that don't charge demand charges, or straight up utility owned chargers.
Oh, well that certainly puts this in a new light if they don't even have demand charges to deal with or to be avoided.

I was thinking of these two cost items, which would be higher for a standard station with a higher power connection:
1. High demand charges
2. Higher cost construction/install/utility transformer

The battery-included station type would save money in those two areas, but offset with higher equipment price. I wasn't sure of which side of that equation would be higher. And I was trying to get away from the idea that they just won't be built. These sites do eventually get SOMEthing. It's a question of which would be the most cost effective one.
 

I really like the idea of simply rate basing DCFC. The money is there and utilities can more easily negotiate demand costs than a 3rd party that doesn't own the lines and transformers. The biggest problem is that you're basically giving up on a competitive market for fast charging but if that's not economically feasible anyway it won't matter. Build a DCFC network in a similar way utilities build transmission lines. Where there's a need or congestion build or add more stations. With renewables slowly eating into their build and grow business model I'm sure most of them will be grateful to have a new opportunity to build and grow.
 
Those costs are all about ensuring you have the infrastructure to support 'coincident peak' which generally occurs around ~4pm in the summer. My point is that demand fees need to take this into account.
Right, but unless there's a way to 100% prevent using electricity during those periods, then everything still needs to be sized on the assumption that your usage might be coincident to the peak on occasion.
 
Right, but unless there's a way to 100% prevent using electricity during those periods, then everything still needs to be sized on the assumption that your usage might be coincident to the peak on occasion.

Why not just charge them based on much they use during that period? Shouldn't using 100KW at 4pm be more expensive than using 100kW at 4am? Should a station that uses 100kW at 4am then cuts back with batteries to <10kW at 4pm pay the same demand fees as a station that doesn't cutback at 4pm? Shouldn't there be some economic incentive to smart load management?
 
Imagine being Tesla or EA or any others and wanting to place DC Charging locations in different utility territories? With each utility having its own rate structure and willingness to negotiate (not to mention site location, permitting and other issues they run into). The complexity of rates just within some utilities can be large, let alone across utilities. Some offer peak/off-peak/shoulder rates, some offer demand charges and the sizing that could trigger rates can vary as well.

I do wonder if this is part of what is triggering utilities to group up and deploy EV charging themselves like with the Electric Highway Coalition. It also doesn’t hurt that it puts this new load in their territories instead of neighboring ones.
 
That's why demand fees need to either take into account the time of day or simply use TOU instead. 200kW demand on the grid at noon is generally going to be a good thing and pulling from an onsite battery when there's surplus energy on the grid would be a bad thing. During the 'neck' of the duck curve is a different story. That's why demand fees are generally a bad idea... they don't take into account WHEN that demand occurs. Pulling 30kW from the grid at 7pm should cost MORE than pulling 300kW from the grid at 11am.

If I'm fast charging in Oklahoma at 11pm it would be kinda silly for the charger to throttle to 30kW because the battery is drained while the wind turbine 500m away is getting cutback because there's too much wind....
Granted, but the demand fees are (at least in part) a reflection of infrastructure costs.
It's just too bad that the utilities have in some cases subverted their intended use.
 

I came across some interesting "real" world numbers for DCFC in a presentation that some Tesla folks gave to the Alaska Energy Authority's EV Working Group. Here's the most relevant part:

-commercial customers are usually >50% load factor, not true for DCFC today
-congestion at charging stations at 30% LF, negative customer experience so don't want to go above that!
-CEA [Chugach Electric Association] case, for 8-charger tesla DCFC: at 5% LF - pays 63 cents/kWh! (at 30% - 20 cents per kWh, down to ~17.5 cents at 50% and above).
-a really busy station is around 20%, often down to 5%
 
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I'd be a lot more ok with the FreeWire concept if it used a bi-directional inverter to help off-set the demand charges of a larger service instead of just the charger. The usage factor is likely going to be <5% at most of these locations so now in addition to a $50k DCFC you're also anchoring a ~$100k battery to a ~5% usage factor. In many ways it just makes a bad situation worse.

I think we just need TOU at DCFC. If you want to charge at 150kW during peak hours it's gonna cost $1/kWh.
 
I’ve wondered, is there really $50k worth of electronics in a single 150kw DCFC?

Also what is the cost difference to build a ten pump gas/diesel fuel station and a ten stall DCFC station?

Just trying to understand the economics because DCFC’s seam to be cost prohibitive, not including electrical demand charges.
 
I’ve wondered, is there really $50k worth of electronics in a single 150kw DCFC?

Also what is the cost difference to build a ten pump gas/diesel fuel station and a ten stall DCFC station?

Just trying to understand the economics because DCFC’s seam to be cost prohibitive, not including electrical demand charges.

Power electronics seem to run ~$1k per 10kW so 150kW DCFC is probably ~$15k plus all the assembly, support equipment, engineering and markup so ~$50k is probably about right.

Google says a gas station costs ~$2M but they also don't make much money selling gas. As the video in the OP pointed out they use the gas to lure drivers through and make their profit on the attached convenience store. I would expect DCFC to function in a similar way. But the trick with DCFC is that 90% of charging is done at home but you still need the ability to handle holiday surges which really screws up the usage factor.
 
Power electronics seem to run ~$1k per 10kW so 150kW DCFC is probably ~$15k plus all the assembly, support equipment, engineering and markup so ~$50k is probably about right.

Google says a gas station costs ~$2M but they also don't make much money selling gas. As the video in the OP pointed out they use the gas to lure drivers through and make their profit on the attached convenience store. I would expect DCFC to function in a similar way. But the trick with DCFC is that 90% of charging is done at home but you still need the ability to handle holiday surges which really screws up the usage factor.
I am building a charging station/convenience store in mid-Michigan, and I am faced with these issues. However, I am building on a site that already has 15kV service, so infrastructure is less of an issue. I am going to put in between 300kW and 1MW of solar as well. I will probably put in around 300kWh of batteries, but that is more to store up my sunlight, than to offset demand charges. I am hoping to be hooked into the grid as cogeneration, rather than just as a consumer.

Greg Jensen
[email protected]
 
I am building a charging station/convenience store in mid-Michigan, and I am faced with these issues. However, I am building on a site that already has 15kV service, so infrastructure is less of an issue. I am going to put in between 300kW and 1MW of solar as well. I will probably put in around 300kWh of batteries, but that is more to store up my sunlight, than to offset demand charges. I am hoping to be hooked into the grid as cogeneration, rather than just as a consumer.

Greg Jensen
[email protected]

Just be careful. The price or even the fact of the utility buying your excess generation is at the whim of the legislators in your area. Some states have mandated the utilities to pay for excess solar generation only to nullify the law a few years later leaving many PV owners stuck with more energy than they can use and no way to amortize their installation. I'm just sayin'.
 
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Just be careful. The price or even the fact of the utility buying your excess generation is at the whim of the legislators in your area. Some states have mandated the utilities to pay for excess solar generation only to nullify the law a few years later leaving many PV owners stuck with more energy than they can use and no way to amortize their installation. I'm just sayin'.
Hence the batteries. I expect to always be a net consumer of electricity and will only sell to the utility when the sun is brightly shining, the batteries are fully charged, and nobody is at the chargers.
 
My concerns with charging costs is more along the lines of what happens to Supercharging if Tesla encounters financial trouble or simply decides to divest the charging network. I have free supercharging. What happens if the network is opened up to other automakers and they don't like providing me with free charging. Likely the network becomes a third party spin off with multiple owners and free supercharging dies. :-(

I highly doubt Tesla will withdraw from supercharging. The value proposition of the Semi relies entirely on there being a megacharger network. Sure, Tesla could run into financial trouble such that a retreat from supercharging isn’t voluntary, but their future plans rely on a doubling down on investment in expanding recharging infrastructure for even faster charge rates.
 
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The value proposition of the Semi relies entirely on there being a megacharger network.
No it doesn't. 99.999% of Semi charging is going to happen at trip end points because no one is buying one (of the current design) to use for long distance, over-the-road (OTR) trucking. It's design is great for use in drayage or intermodal, not OTR trucking. For a long time Megachargers are only going to be built at the distribution hubs of Tesla Semi fleet operators and at intermodal terminals (ports/railyards). With maybe a couple of exceptions, like along I-5 between SF and LA (or really San Pedro/Long Beach and Oakland), don't expect Tesla to build any megachargers out in the wild.
 
Hopefully they upgrade their 25kW DCFC in Clines Corner. ~$1/kWh is a bit eye watering.

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I thought it would be worth having a thread to discuss how difficult and perhaps impossible it's going to be for L3 charging to operate as a viable business. One fact about electric billing very few people have experience with is demand billing, being billed per kW in addition to per kWh. In SE NM Xcel charges $15.40/kW in the winter and $18.49/kW in the summer. So if you want to have 250kW fast charging a single car charging at that rate sets your electric bill at ~$4600/mo. Even if rates are set as high as $0.40/kWh and the average car takes 50kWh you would need to charge 230 cars per month or 7 per day just to break even on demand billing and that's just a single stall. Obviously more stalls = higher demand fees and that's not counting the cost of electricity per kWh or the cost of the equipment which is also substantial.

For DCFC to be economically sustainable it needs to collect revenue from all parties that share in it's benefit. The manufacturer, the host, the driver, other local businesses.

There's a great video on YouTube with the CEO of charge point where he points out that gas stations don't make money selling gas... they make their profits from the attached convenience store. Economically selling electrons is even worse than selling gasoline.

Or they can just make the power company’s provide it as a service. Then spread the cost over everyone. Eventually that’s where we will be at.