Insights Data Products

Definitions and methodologies - Reliability

 

Welcome to the Zapmap Insights data products subscriber help page.

In here you'll find all of the field definitions and calculation methodologies to super-charge your value realisation, whether you're a Profile, Monitor, or Empower customer.

 

 

Reliability

Background

The Zapmap consumer app uses 4 statuses: Available, Charging, Unavailable, and Unknown, which are derived from the statuses (both OCPI - many versions - and bespoke) returned by more than 75% of the UK's charge point network.

The data was - and continues to be - collected for the purpose of informing the consumer base whether a device is available to connect to, or not.  It was not collected for reliability purposes, therefore assumptions have been made.

The status data is held at a physical device level, rather than EVSE.  This will have the effect of recording Available if a single device has more than one  EVSE, and at least one is online and able to be used.

The status data held covers every minute from the moment the "dynamic" (Zapmap speak for "live") charge point is added to the database.

 

For the purposes of this Reliability analysis, these Zapmap statuses have been mapped to:

Zapmap statusPCPR status
Available or ChargingIn service
UnavailableOOS
UnknownExempt

The PCPR Reliability requirements only apply to Rapid and Ultra-rapid EVSE. 

Pre-2024, Zapmap has not - in its line of business - recognised EVSE as a measurable unit base, instead preferring the consumer-friendly physical device.

The power rating of a physical device is attributed using the maximum power of the highest rated connector across all - where applicable - internal EVSE.

A device with a 22kW and a 150kW connector is allocated Ultra-rapid, as 150 > 22.

 

Definitions & Methodology

Each 24 hours, is been split into 288 individual 5-minute blocks.  The status recorded for each individual device during each 5-minute block is collected and aggregated.              

At the end of 2023, this is approximately 10 million rows of status data per day, or 1 billion rows per quarter.              

               

In this situation, and for the purpose of Reliability reporting, a PCPR status is derived using the following hierarchy:

Any “In Service” Zapmap statuses during the 5-minute block, the 5-minute block shall be mapped to “In service”.
Else, if there are any “Time Exempt” statuses during the 5-minute block, the 5-minute block shall be mapped to “Time exempt”.
Else, if there are any “Out of Service” statuses during the 5-minute block, the 5-minute block shall be mapped to “OOS”.
Else, "Other".

The device-level statistics are aggregated up to give a total in minutes, for "In service", "OOS", "Time Exempt", and "Other".

"Other" is a QA check.  A zero count for "Other" ensures all 5-minute blocks are accounted for, enabling a simplified Reliability calculation to be completed:

i.e. In service + OOS + Time Exempt + Other = All possible minutes

If Other = zero, then all possible minutes are accounted for within the remaining 3 statuses.

 

Reliability therefore becomes:

Reliability calculation

The above calculation is applied to the aggregated data.

Profile

Download the aggregated background data by following the link in the sidebar.

 

Monitor

Download the granular background data using the Carto download facility, or connect to the API here: .....

 

Empower (coming soon)

Connect to the near-live data through Google Analytics Hub