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Supercharging rates go WAY up!

OK with increased supercharging rates?

  • Yeah, gotta pay for the Supercharger infrastructure.

    Votes: 275 67.2%
  • What happened to charging not being a profit center?

    Votes: 93 22.7%
  • It will affect my future vehicle purchases.

    Votes: 23 5.6%
  • Nope, no idea what the cost will eventually be.

    Votes: 18 4.4%

  • Total voters
    409
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According to Pacific Power's website, the US national average COMMERCIAL power rate is 10.74 cents/kWh.
Prices range from 7.16 to 24.96 (probably Hawaii) cents per kWh.

17645-20_UtilityRateMap_Commercial_F.jpg


Commercial Price Comparison
I have a feeling this is a bit misleading. This is probably based on base rates?
 
I have a feeling this is a bit misleading. This is probably based on base rates?
Pretty much guarantee it. It'd be very difficult to condense and display all the data on peak usage surcharges and so on in something that simple.

EDIT: The prices also vary a lot across some states. The number listed for WA for example is a lot higher than prices you'll find in the interior, next to all those hydro dams. That's why all those Bitcoin firms had set up shop there, as BTC is basically converted electricity so profitably for those firms is highly dependent on very cheap local power (or stealing it :p ).
 
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The webpage says, "average commercial rates by state." So, yes, prices vary within each state.
Yea but even then... Superchargers probably get hit with high usage charges, but if you average all hours of the day and all times of night those prices may be closer. However, usually these statistics are for the power rate, EXCLUDING fees.
Check out this page:
San Diego, CA Electricity Rates
Here is what we actually pay:
https://www.sdge.com/sites/default/files/regulatory/1-1-19 Schedule DR Total Rates Table.pdf

You can see it's easy to skew things just using the energy rate. From the SDGE PDF you can see that the electric rate is only about $.16/kWh for SD residents but the actual price we pay can be up to $.54/kWh after fees. Transmission, Distribution, plus PPP ND CTC LGC RS TRAC (whatever that stuff is).
 
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Calculating actual effect of demand charges:
Peak demand charges look high, but they depend on the ratio of average use and peak use. Assume a 12 stall super charger at 120 KW peak for each pair. Schedule 34 for commercial power here is $0.0491/kwh and $6.77 per kw demand. Assuming each charger is in use at 120 kw equals a 720 kw peak demand worst case. If use is low, say and average of 120 kwh/day the total rate KW demand$ + KWH$ = $0.11/kwh where the demand and KWH charges are appx equal. If the average is 360 kwh/day the rate goes down to $0.07/KWH. So the higher the usage rate, the smaller effect demand charges are.

This is in Washington, your relative rates and demand charges will vary. This location started at $0.11 and is now $0.31. Residential rate is $0.0816
 
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Peak demand charges look high, but they depend on the ratio of average use and peak use.
Having very uniform [high] use helps mitigate the peak demand surcharges' impact but it still represents a very real increase over the base rate that people try to use for running napkin math economics. It also requires business that isn't heavily cyclic through the day and week. The nature of 25 - 40 mins for most customers and just random arrivals means if you're running near full capacity you're going to often backlog substantially, and the time of average backlog will rise exponentially as you approach closer to average full capacity. This is because of a rapidly rising risk of collisions of charging windows.

Then there is the practical matter of it that it is incredibly rare to have nighttime or even shoulder times demand for charging match peak demands. It simply isn't going to be smooth like that, not like you see in things like shift-work manufacturing facilities and so on. So you're starting from substantial holes in the charging demand for the day.
 
Demand charges are typically based on the highest average kW over any 15 minute interval in the daily eligible period during the month.

This happened to a town near me recently that has community L2 chargers. They had never had more than one car charge at a time until one day that a local event filled up all 4 6 kW EVSE for 3 hours. Those 3 hours cost them $360 in extra demand charges to supply 54 kWh

Our local 'high power' rate is 4.3 cents a kWh + $30 a kW demand charges. The most expensive corner case is $120.0175 a kWh
If an average Supercharger location averages 1 station used 24/7 and a peak of 4 stations used anytime during the month the charges per kWh would be ~ ($120+732*0.043) / 732 = 21 cents a kWh
 
Demand charges are typically based on the highest average kW over any 15 minute interval in the daily eligible period during the month.

+1000

point being you can ave a single momentary demand spike and it will completely change the calculation for the entire month even if a SCer was mostly idle.

($120+732*0.043) / 732 = 21 cents a kWh

i'm not following where the 732 came from? is it just the number of hours in a month? Thanks for taking the time to explain.
 
i'm not following where the 732 came from? is it just the number of hours in a month? Thanks for taking the time to explain.
Yes,
365 days in a year
24 hours in a day
-> 365*24 = 8760 hours in a year

12 months in a year, so
8760/12 = 730 hours per month.

Thanks for catching the error ;-)
I estimated by taking 30.5 days in a month.
Someone is going to take me to task for not using 365.25 days in a year ... and then all hell will break loose.

point being you can ave a single momentary demand spike and it will completely change the calculation for the entire month even if a SCer was mostly idle.
Exactly.
We want (really) fast charging, and we want multiple stations to avoid charging delays. Those are expensive conveniences.
 
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