The “P” stands for “Pool”, as the company which became Elexon was called the “Electricity Pool of England and Wales”. Generally, P-flows are included in BSCPs to define a required exchange of information.

Most P-flows have a defined structure, but some don’t – and there is no specified file format or transfer mechanism. 

“P-flows” were called this to distinguish them from “D-flows”. P-flows are numbered Pxxxx (e.g. P0282).