I have reviewed the documents in detail and provided tracked changes in the following  documents.

• Comments on energy products
• Comments on energy flows

I do not claim to be an energy expert or be cognisant of the technical terminology in many of the definitions, so many of my comments are queries rather than corrections.

For the definitions to be adopted as SIEC, there is still quite a bit of work to be done. Mr Simmons made it clear in his notes that "Points which relate to reporting have been avoided wherever possible as this is the responsibility of those who prepare the questionnaires", and while this is understandable, it creates problems for those who prepare the questionnaires or other reporting tools. Respondents reporting information require very clear definitions of the products/flows for which they are reporting (preferably in non-technical terminology since those reporting will not always be energy experts), which are both mutually exclusive and exhaustive of the products/flows to be reported. In my reading of the definitions it is not clear that such mutual exclusivity and exhaustiveness has been achieved.

To progress this issue, I have compiled a rough first draft of an energy products/flows classification system (see "Energy class'n") from the definitions in the attached documents. Although this draft clearly requires further work (e.g. by taking into account responses to my comments in the two documents), it does provide a basis for determining which product/flow definitions are not mutually exclusive and what may be missing in order for the definitions to be exhaustive.

Another important aspect of the SIEC is the need for a hierarchical structure to enable the aggregation of data at higher levels of the classification, which will be required for some statistical applications of this classification.

To progress the SIEC to a quality classification, I feel that a classifications expert and an energy expert (perhaps Mr Simmons?) need to be engaged to ensure that the attached documents can be developed into a classification suitable for statistical purposes (requiring a classifications expert), while retaining the technical; accuracy of the energy definitions (requiring an energy expert).

Finally, the flows document needs some additional explanation when applied for statistical purposes. In a National Accounts context, "flows" refers to the financial transactions which flow through the economy. This is clearly not the case for the flows defined here. This is not a problem at all (and is similar to other environmental flows being dealt with by the London group such as water flows), but a note clearly stating that energy flows are not to be confused with the traditional national accounts concept of flows would be useful (this could easily be achieved through the preamble of SIEC once developed)."

I hope these comments and input are useful.

Regards
Graeme