Why does tiered pricing punish the fastest charging?

[sorka]

Currently driving a P85D with unlimited free supercharging. Placed an order for a Plaid X but now having second thoughts about it now after seeing the tiered pricing changes. Didn't even realize it until today.

So it appears that the cost per kwh rises dramatically with each tier. So you get punished for pulling in with low SOC, charging fast, and getting out fast. WTH? Why?????
Why can't they just charge a flat rate for kwh based on time of day. i.e. peak and off peak but the cost is the same per kwh regardless of how fast you charge.

Is there anyway to find out what the prices are in California? My nav doesn't show pricing because I have free supercharging. I'd love to see what typical pricing is along long distance routes I normally travel.

 

[miimura]

Tiered pricing is by time of day in California with higher $/kWh during the daytime. In states where they cannot charge for energy (kWh), the tiers charge more per minute the faster that you charge. That is their way of approximating roughly equal cost per kWh over time.

AFAIK, the only way to see the prices of any given Supercharger site is to check in on a car's screen that doesn't have free Supercharging.

 

[sorka]

Tiered pricing is by time of day in California. In states where they cannot charge for energy (kWh), the tiers charge more per minute the faster that you charge. That is their way of approximating roughly equal cost per kWh over time.

AFAIK, the only way to see the prices of any given Supercharger site is to check in on a car's screen that doesn't have free Supercharging.

Yes, but it's not linear. 180-250 kw @ $1.35 / minute is much more expensive per kwh than 0-60 kw @ $0.12 / minute.

 

[miimura]

Yes, but it's not linear. 180-250 kw @ $1.35 / minute is much more expensive per kwh than 0-60 kw @ $0.12 / minute.

The first 5 minutes of 250kW charging is $0.3375/kWh while the last 5 minutes of 21kW charging would cost the same

 

[sorka]

The first 5 minutes of 250kW charging is $0.3375/kWh while the last 5 minutes of 21kW charging would cost the same

21kw?

 

[miimura]

21kw?

That's where the cost is equal. Personally, I don't usually charge at Superchargers below about 75kW if I can help it. Driving in CA, it's rarely needed.

For me, I don't really care what the Superchargers cost. They're fast and they cost less than gas and I rarely use them.

 

[mociaf9]

Currently driving a P85D with unlimited free supercharging. Placed an order for a Plaid X but now having second thoughts about it now after seeing the tiered pricing changes. Didn't even realize it until today.

So it appears that the cost per kwh rises dramatically with each tier. So you get punished for pulling in with low SOC, charging fast, and getting out fast. WTH? Why?????
Why can't they just charge a flat rate for kwh based on time of day. i.e. peak and off peak but the cost is the same per kwh regardless of how fast you charge.

Is there anyway to find out what the prices are in California? My nav doesn't show pricing because I have free supercharging. I'd love to see what typical pricing is along long distance routes I normally travel.

Their whole goal with the pricing realignment is to make the "per minute" charging as close to "per kWh" as possible. This means that when charging at higher power, the price needs to be higher as well because in each minute of charging, you're getting more energy. So, for example, let's consider Case A: 3 minutes of charging at 60 kW vs Case B: 3 minutes of charging at 180 kW. For A, in those 3 minutes your car actually got 3 kWh of energy during that time period. For B, your car got 9 kWh, i.e. three times as much energy in those same 3 minutes. If the goal is to have a pricing tier strategy that as closely as possible approximates a per kWh price for the energy then the tier at 180kW needs to cost three times as much per minute for that to work.

Basically, what Tesla did is realigned their pricing tiers for locations that charge by the minute so that even though you are technically charged by the minute the end result works out to you effectively paying a price that is very close to their desired $/kWh target.

As for why they don't just always charge by the kWh, they can't. Tesla would like to do just that, but in many places they are prevented from doing so because "reselling" electricity isn't allowed in those locations. The price "per minute" is a hack to get around that restriction.

 

[sorka]

Their whole goal with the pricing realignment is to make the "per minute" charging as close to "per kWh" as possible. This means that when charging at higher power, the price needs to be higher as well because in each minute of charging, you're getting more energy. So, for example, let's consider Case A: 3 minutes of charging at 60 kW vs Case B: 3 minutes of charging at 180 kW. For A, in those 3 minutes your car actually got 3 kWh of energy during that time period. For B, your car got 9 kWh, i.e. three times as much energy in those same 3 minutes. If the goal is to have a pricing tier strategy that as closely as possible approximates a per kWh price for the energy then the tier at 180kW needs to cost three times as much per minute for that to work.

Basically, what Tesla did is realigned their pricing tiers for locations that charge by the minute so that even though you are technically charged by the minute the end result works out to you effectively paying a price that is very close to their desired $/kWh target.

As for why they don't just always charge by the kWh, they can't. Tesla would like to do just that, but in many places they are prevented from doing so because "reselling" electricity isn't allowed in those locations. The price "per minute" is a hack to get around that restriction.

Got it. So the examples I was seeing in articles where the average was in tier for was double what the average per kwh in tier 1 was probably a bad or old example and Tesla has tuned that over time?

Can someone post some tier pricing examples from their nav? I have FUSC so I have no visibility into charging costs. Is there anywhere one can see charging costs without having a car that has pay as you go?

 

[Rocky_H]

Why can't they just charge a flat rate for kwh

State laws. It's not just a problem Tesla has. Chargepoint and Blink and all of the charging networks have that issue. Some states (less than half now I think) still have laws outlawing anyone but the state monopoly utility companies from selling electricity.

So the EV charging network companies all have to just roll their eyes and say, "Ugh, fine. You are (exaggerated finger quotes) "renting time" using our equipment."

So the examples I was seeing in articles where the average was in tier for was double what the average per kwh in tier 1 was probably a bad or old example and Tesla has tuned that over time?

That aren't going to be able to fully tune it out unless they want to go to like twenty-some tiers to give them enough granularity, and then people's eyes would glaze over at the rate plans, and they would be angry at Tesla for making it too complicated, etc. So they pick a middle ground with just a few tiers so it's at least semi-understandable, but that's going to have some inequality points somewhere in that spectrum.

 

[sorka]

State laws. It's not just a problem Tesla has. Chargepoint and Blink and all of the charging networks have that issue. Some states (less than half now I think) still have laws outlawing anyone but the state monopoly utility companies from selling electricity.

So the EV charging network companies all have to just roll their eyes and say, "Ugh, fine. You are (exaggerated finger quotes) "renting time" using our equipment."


That aren't going to be able to fully tune it out unless they want to go to like twenty-some tiers to give them enough granularity, and then people's eyes would glaze over at the rate plans, and they would be angry at Tesla for making it too complicated, etc. So they pick a middle ground with just a few tiers so it's at least semi-understandable, but that's going to have some inequality points somewhere in that spectrum.

I just meant that in the examples I've seen tier 4 is almost twice as expensive as tier 1 per kwh.

 

[mociaf9]

Is there anywhere one can see charging costs without having a car that has pay as you go?

nope, there isn't.

 

[vikingrob]

Their whole goal with the pricing realignment is to make the "per minute" charging as close to "per kWh" as possible. This means that when charging at higher power, the price needs to be higher as well because in each minute of charging, you're getting more energy. So, for example, let's consider Case A: 3 minutes of charging at 60 kW vs Case B: 3 minutes of charging at 180 kW. For A, in those 3 minutes your car actually got 3 kWh of energy during that time period. For B, your car got 9 kWh, i.e. three times as much energy in those same 3 minutes. If the goal is to have a pricing tier strategy that as closely as possible approximates a per kWh price for the energy then the tier at 180kW needs to cost three times as much per minute for that to work.

Basically, what Tesla did is realigned their pricing tiers for locations that charge by the minute so that even though you are technically charged by the minute the end result works out to you effectively paying a price that is very close to their desired $/kWh target.

As for why they don't just always charge by the kWh, they can't. Tesla would like to do just that, but in many places they are prevented from doing so because "reselling" electricity isn't allowed in those locations. The price "per minute" is a hack to get around that restriction.

Taken to a logical extreme, you could see a per-minute price schedule that looks like this:

0-30 kW: 0.15

30-40 kW: 0.20

40-50 kW: 0.25

50-60 kW: 0.30

60-80 kW: 0.40

80-100 kW: 0.50

100-120 kW: 0.60

120-150 kW: 0.75

150-200 kW: 1.00

200-250 kW: 1.25

 

[ka9q]

It's possible they want to charge more at the higher power levels to recover their utility demand charges. They can be substantial.