What's a fair price for the supercharging option?

[bonnie1194]

My bet is that Tesla will only find partners to install the Supercharger network locations & won't be involved at all beyond that. The entity who owns the real estate where the charger sits will be the one to decide fees, if any. I don't know how it could work any other way.

[Doug_G]

Robert.Boston is right... by my calculations in Ontario a single use of a Supercharger could potentially increase your power bill by nearly $1000 if it pushed you into demand charge levels. Of course every use afterwards is "free" from that perspective.

[3lectronica]

I don't buy the technical issues - Leaf and iMiev can DC quick charge.

DC quick charge stations for the Leaf and iMiev are 50kWh max. Tesla Superchargers are 90kWh! They would bring a Leaf to 80% in about 12 minutes (not healthy), compared to the 30 minutes Nissan quotes. I'm certain that Tesla has limited the SC access to the 60 and 85 kWh packs for this very reason.

[doug]

DC quick charge stations for the Leaf and iMiev are 50kWh max. Tesla Superchargers are 90kWh! They would bring a Leaf to 80% in about 12 minutes (not healthy), compared to the 30 minutes Nissan quotes. I'm certain that Tesla has limited the SC access to the 60 and 85 kWh packs for this very reason.

Units!

[markb1]

DC quick charge stations for the Leaf and iMiev are 50kWh max. Tesla Superchargers are 90kWh! They would bring a Leaf to 80% in about 12 minutes (not healthy), compared to the 30 minutes Nissan quotes. I'm certain that Tesla has limited the SC access to the 60 and 85 kWh packs for this very reason.

In theory, they could reduce the wattage for smaller batteries. It would stand to reason that you could safely get 80% charge on the 40kWh pack in the same amount of time that you could safely get 80% charge on the 85kWh pack, because it would take less wattage to do it.

[drees]

Robert.Boston is right... by my calculations in Ontario a single use of a Supercharger could potentially increase your power bill by nearly $1000 if it pushed you into demand charge levels. Of course every use afterwards is "free" from that perspective.

That's pretty cheap. Demand chargers in the summer here in California can easily double that if not more.

In theory, they could reduce the wattage for smaller batteries. It would stand to reason that you could safely get 80% charge on the 40kWh pack in the same amount of time that you could safely get 80% charge on the 85kWh pack, because it would take less wattage to do it.

Yes, exactly. 90 kW Supercharge for 85 kWh packs (1.06C), 64 kW Supercharge for 60 kWh packs and 42 kW Supercharge for 40 kWh packs.

Because of the demand charges, to make each incremental charge is much cheaper than the first one each billing period. Say your demand charge is $10/kW and energy charge is $0.10 / kWh. The first 90kW supercharge that lasts 30 minutes will cost $1000 + 45 * $0.10 = $1004.50. But each subsequent charge will only cost another $4.50, cutting the cost to $504.50 / charge. If you want to get the cost for a 30 minute 90 kW Supercharge session down to $10, without losing money, you need to get at least 182 sessions in per month ($1000 + $4.50 * 182 = $10 per 90 kW 30 minute charge session). And that's just to break even on the utility charges - never mind the $100k it can cost to install such a station, maintenance and insurance.

That's 6 sessions / day - with most charging likely to happen in a few hours per day, it's clear that you need volume to make this cost effective. That means you need to include the 60/40 kWh cars since these cars are actually more likely to need a Supercharge (even at a slower rate). That means a "smart" charging station with multiple nozzles which manages total demand to say 100 kW so that the next car can start charging as soon as possible. Or if 40/60 kWh cars are charging, multiples of those cars can charge at the same time since their max rate will be much lower. Not to mention that as cars reach full, the charge rate will slow down to avoid overheating the batteries.

[brianman]

In theory, they could reduce the wattage for smaller batteries. It would stand to reason that you could safely get 80% charge on the 40kWh pack in the same amount of time that you could safely get 80% charge on the 85kWh pack, because it would take less wattage to do it.

The headline is already written: "Tesla supercharger is a scam, it charges at the same rate as the dryer outlet on my car."

There's also the "driving 10 mph in the left lane of a 70mph freeway" problem. (But charging rate, not driving speed.)

[rabar10]

That means a "smart" charging station with multiple nozzles which manages total demand to say 100 kW so that the next car can start charging as soon as possible. Or if 40/60 kWh cars are charging, multiples of those cars can charge at the same time since their max rate will be much lower. Not to mention that as cars reach full, the charge rate will slow down to avoid overheating the batteries.

This would be difficult/expensive to do using DC fast chargers, which track the battery voltage of the car while charging.

[drees]

This would be difficult/expensive to do using DC fast chargers, which track the battery voltage of the car while charging.

Not hard to do at all for someone who can build a DC QC station. Each DC charging station is capable of running standalone so tracks voltage/current based on what the car is asking for and what the charging station is able to provide.

Each DC charging station knows how much power is being pushed to each car. The group knows the maximum power that can be pulled from the grid. From there it's just a matter of adjusting maximum allowable power output of each charging station as desired.

[VolkerP]

We touched this topic in another thread so I think it's time to draw a result on this poll. I averaged the money interval boundaries, where I assigned $0 to the "no cost" option and $3,000 to the ">$2,000" option. The average of the votes of 79 participants is $429.