Comments on Energy Interoperation Common Transactive Services (CTS) Vers

The definition of âScaleâ in Table 3-3 appears to be incorrect. âScaleâ is defined there as the âMantissa that specifies the size of the Resource Unitâ and the example given states that âmegawattsâ has a mantissa of 6. Assuming we are working in base 10, the prefix âmega-â refers to the 6th power of 10 (10^6), where 6 is the EXPONENT of the number, not the mantissa. In standard scientific notation, âmantissaâ refers to the digits without the 10^n part. Therefore, the definition of âscaleâ should be the EXPONENT of the size prefix (âmegaâ or 6 in the example), not the mantissa (the fractional part or âprecisionâ of the number).

Nevertheless, the effect of the definition of scale is correct: the example for âSizeâ (â5 kWâ), with the explanation that the â5â is the âsizeâ and â3â is the âscale,â makes sense, since the scale part of this is âkilo-â (10^3) and thus the exponent (NOT the mantissa) of 5 x 10^3 is â3â. But why is âSizeâ constrained to be an âintegerâ? Why not allow a Product to have a fractional Size (for example "0.5 MW") rather than requiring this to be expressed as â500 kWâ (or even â500000 Wâ)?

Iâm not sure that I understand the example of âStream Payload Mantissaâ in Table 5-1, but it seems to contain the same confusion between mantissa and exponent.

The definition of âQuantity Scaleâ in Table 6-2 definitely confuses mantissa and exponent.

When discussing Conformance (Section 14), line 780 says âPortions of CTS conform to and use updated and simplified versions of the specificationsââ. I guess itâs possible for a specâs conformance rules to allow the CTS spec to both conform to it and to extend it, but it does sound somewhat paradoxical. Besides, the WS-Calendar spec says [lines 1553-1554] that "Specifications that...claim conformance with WS-Calendar SHALL define the business meaning of zero duration Intervalsâ and I don't find that in the CTS spec.

Some miscellaneous typos:

Line 356: âthat to shallowâ should probably read âthat are too shallowâ.
Line 668, âreport and powerâ should probably read âreport any powerâ.
Line 712: âmatch buy andâ should probably read âmatch buyer andâ.
Line 912: âseller increaseâ should probably read âseller to increaseâ
Line 914-15: âthe senderâ should probably read something like âthe identities of the senderâ.
Line 916: âable detectâ should probably read âable to detectâ.

Walt

H. Walter Johnson, Ph.D.

Smart Grid & Energy Consulting

mobile: 1.916.802.8370

hwjohnson@ieee.org

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