Abstract: Meters and meter covers comprising: a removable cover housing configured to accommodate the upper portion of the internal components of an existing meter, the cover housing engageable with the housing base of the existing meter to cover and enclose the internal components of the existing meter; a sensor affixed to the cover housing, the sensor configured to collect environmental information pertaining to the local external environment of the existing meter; a wireless radio affixed to the cover housing, the wireless radio configured to transmit the environmental information to the existing meter or to a remote server in communication with the existing meter; and a power unit affixed to the cover housing, the power unit supplying power to the sensor and the wireless radio.

Abstract: A parking meter receives data indicative of a remote payment being completed and displays an amount of time purchased by the remote payment for a parking session. The parking meter determines an amount of time remaining in the parking session and powers down at least a portion of a meter communication subsystem subsequent to receiving the data indicative of the remote payment being completed. The parking meter wakes up the powered down portion of the communication subsystem upon determining that the amount of time remaining is below a threshold time, and can receive an indication of additional time being paid for remotely, and can update the displayed time remaining to reflect the additional time.

Abstract: A power supply unit for supplying power to a device has a rechargeable, main battery; a charging arrangement for charging the main battery; a non-rechargeable back-up battery; load terminals for connection to a load; and a control unit for controlling supply of power to the load primarily from the main battery and secondarily from the back-up battery. The device is, in particular, a single bay, stand alone parking meter. In the event that the main battery runs low, the control unit is configured to supply power to the load from both the main battery and the back-up battery or only from the back-up battery. The back-up battery is easily replaceable, and the power supply unit has a bay, with connectors for receiving the back-up battery. The main battery is charged from solar panels. A communication device is provided to communicate status messages wirelessly to a control system.