Current or Future Solar Customer Adding EV (on TOU)
If you have or plan to install solar panels and wish to adopt the TOU Rate for EV Charging:
If you have or plan to install solar panels and wish to adopt the TOU Rate for EV charging, CMLP will require you to locate your second meter on the line side (street side) of your house meter. (See meter socket wiring diagrams for 200 amp and 320 amp systems here)
CMLP’s incoming overhead or underground feeder wires deliver electricity to the “line side” (street side) of your house meter. The electricity passes through the meter to wires on the “load side” (house side) of the meter. These wires convey the electricity to the interior electrical panel that distributes it via circuits throughout your house.
Locating the second meter on the line side of your house meter ensures that the meter will not mistake electricity produced by your solar panels for electricity delivered by CMLP and erroneously charge you (rather than refund you) for the electricity your panels are producing. This is necessary because the meters currently used by CMLP do not have the technological capability to track how much power is being used during off-peak vs. on-peak periods, and simultaneously track whether power is being delivered to you from the grid vs. being sent back to the grid from your solar panels.
A side effect of locating the second meter on the line side of your house meter is that only electricity delivered by CMLP will charge your EV. Electricity generated by your solar panels will power your house, but not your EV.
However, if there are months of the year when your solar panels produce more electricity than your house needs, there is an option that allows you to opt out of the TOU Rate and charge your car at the regular Residential Rate at any time of the day or night during those months. This involves installing a transfer switch with your second meter.
During months when you have excess solar electricity for charging your car, throw the switch to disable the second meter. Once the switch is thrown, solar electricity produced by your panels will feed your car as well as your home. Any electricity that CMLP delivers to you while the 2nd meter is disabled, either for EV charging or household needs, will be measured by your house meter and charged at the regular Residential Rate. The current Residential Rate is based on three tiers of monthly usage:
a) First 657 kWh: 15.9¢ / kWh
b) Next 178 kWh: 17.0¢ / kWh
c) Any use above 835 kWh: 19.2¢ / kWh
Please note that including the transfer switch in the electrical work to accommodate a second meter is expected to add hundreds of dollars to the cost. (See meter socket wiring diagrams for 200 amp and 320 amp systems here)
If you choose the transfer switch option, CMLP strongly suggests that you join our peak demand reduction Google group, which will allow us to send you an email when peak demand is predicted. Thirty percent of your electric bill is directly related to the amount of electricity Concord uses for just one hour during the entire year. That one hour, the peak demand hour, occurs on a hot weekday afternoon during the summer months, typically between the hours of 12PM – 6PM. When you refrain from charging your EV during peak hours, everyone benefits with lower electric rates, since there are higher costs associated with these peaker power plants.