Under current Measurement Canada (MC) rules for the basis of fees for electric vehicle (EV) charging stations (dated June 19, 2017), electricity may only be sold with the provision that the (sub) meter type is “approved by Measurement Canada”.
However, it has been acknowledged by Measurement Canada as late as March 16, 2018 that:
– there are currently no meters approved for this purpose;
– there are no specifications that would lead to approval
– there is no approved means for testing such meters if such testing standards did exist.
Therefore, to comply with the current regulations, although OEM equipment and billing systems include sub-metering technology for fees based on kWhs, time-based fees are still being used out of the fear of being in contravention of Measurement Canada regulations and the potential for associated financial penalties.
However, unlike any other domestic appliance, electric vehicles from different manufacturers or model years or even vehicle types such as plug-in-hybrids have different charging speeds or may use some of the charging electricity to overcome colder weather conditions, precondition the vehicle main battery pack or may be connected to a shared electrical charging circuit – a new technology that is already being deployed in Canada that dramatically reduces EV infrastructure costs in multiple unit buildings.
Because electric vehicles charge at different rates by make and model, ambient and battery temperature, battery preconditioning software, the number of vehicles being charged, time-based fees are unsuitable and unfair to the consumer resulting in significant overcharges and undercharges for electricity.
Paying for electricity by the minute is comparable to paying for water by the minute regardless of the size of the water pipe or the water pressure
Figure 1 below illustrates the real-world circumstances that result in overcharging of up to 450% for electricity on dedicated Level 2 (240 volt) electrical circuits and 850% in cases involving power-shared Level 2 circuits.
First generation electric vehicles, which still comprise a large part of the electric vehicle fleet in some provinces and that are most affordable by lower income Canadians, will typically limit the rate at which a charge is received to 3.3 kW. With a time-bases fee of $1 or $2 per hour, the charge for electricity amounts to 30 cents or 60 cents per kWh respectively. A 1.5 generation EV that will accept a 6.6 kW charge, with a $1 or $2 per hour fee is charged 15 cents or 30 cents per kWh respectfully for electricity valued by the consumer at 11 cents per kWh2 (BC rates).
Since any time-based fee does not discriminate between slow and faster charging vehicles no time-based fee rate could be designed that would either be fair or equitable.
In conditions of shared Level 2 charging, which is vital to the retrofitting of EV infrastructure in multiple unit buildings, the inequities of time-based charging are magnified. There are current cases where shared charging systems result in charges of over $1 per kWh. These charges are not the fault of the charging system but of the directive for time-based fees.
Figure 2 below illustrates the real-world conditions that result in significant overcharging or undercharging for electricity dispensed from high speed (DCFC) charging systems. As high-speed charging stations can dispense electricity at significantly different rates (typically from 24 kW to 350 kW), time-based charging results in two major disruptions to the market:
• If the DCFC dispenser is capable of only 50 kW, then per hour rates ($18 per hour) tend to be geared to the vehicles receiving 50 kW. Vehicles charging at lower rates (very typical) are significantly overcharged.
• If the DCFC dispenser is capable of 125 kW (or higher) then the per hour rates ($46 per hour) tend to be geared to vehicles charging at that rate. Vehicles with low charging rates that cannot accept the 125 kW are significantly overcharged leading to the refusal by, or avoidance by, EV owners to charge at these higher speed units due to the unacceptable high cost.
Both these conditions, which currently exist in Canada, ($18, a PUC in British Columbia. The $46.20 rate is for a private sector DCFC network in Canada) are counterproductive to the objectives of increasing EV ownership and cross-country mobility.
The current time-based requirement from Measurement Canada is an obstacle to higher EV adoption rates:
• EVs may not be purchased particularly by MURB occupants, due to the high cost of time-based energy fees and/or uncertainty about charging costs.
• The lack of fee certainty and the inability to determine the acceptance of overcharging by a large portion of EV owners makes it difficult for potential private sector parties to develop business models and business cases for investing in high speed charging units.
No doubt out of concern for consumer fairness, California has recently (November 2019) banned charging electric vehicle fees for electricity by the minute and has adopted the provisions of the National Institute of Standards and Technology (NIST) Handbook 44 with modifications to account for the current state of technology and to procced with implementation in phases.
California recognized the very minor concern (in terms of the impact on costs) about current sub- metering accuracy and adopted a leadership position and reasonable measures to implement improved accuracy requirements over time while dealing with the significant inequities and undesirable effect on EV adoption rates of time-based fees for EV charging.