Comments
Here, I send comments on “consolidated baseline methodology for zero-emissions
grid-connected electricity generation from renewable sources.”
First of all, this document is interesting as a proposal for methodology, but it needs to
include explanations of the approach behind the methodology presented, and its
appropriateness.
Followings are the comments as we review it.
0. General Comments
In essential, we believe a model that simulates estimating marginal sources is quite
challenging, but the most relevant as a method that specifies “what are the marginal
sources”, therefore, it should be noted and clearly described in the Baseline Chapter
(before the Step 1) that the combined margin method is applied only when the simulation
model is not available.
1. Comments concerning Step 1
a) Simple OM method
It is stated that the Simple OM method can only be used where low cost/must run resources
constitute less than 50% of total grid generation, but this needs to be reconsidered.
We believe that the approach described below is more appropriate.
An appropriate threshold (applicable condition) should be determined by not only based on
a characteristic of the grid (to which the proposed projects are to be connected), such as the
proportion of generated electricity of low cost/must run sources to total grid generation, but
based on a characteristic of the relative amount between the total grid generation and the
total generation of the projects being proposed. (In other words, especially for operating
margin, the threshold should be determined according to the proportion that the total
generation of the projects constitutes relative to the total generation of the grid.)
b) Simple OM with Low-Cost/Must-Run Adjustment
Since this approach is complex and difficult to understand, it is desirable to include an
explanation of the approach behind the methodology presented.
2. Comments concerning Step 2 (Important)
Following explanation should be inserted in the beginning of the Step 2 to make it clear
that in principle, the Build Margin is to be estimated from the energy policy and generation
plans for the country/area where the project is implemented, and should only be calculated
by the method presented if such information is not available. .
In estimating the Build Margin, it is appropriate to base the estimation on information
concerning resources being planned, not on data relating to resources that have already
been constructed even they were built in latest years, or are being constructed. Virtually
most countries regard energy policy as an important national policy issue, and the country's
Comments on Consolidated Meth (grid renewable).doc: 04/06/30 20:00 1/2
energy policies are reflected in resource planning. Consequently, resources planning should
be reflected in the Build Margin.
For instance, countries that have until now constructed equal proportions of LNG-fired
thermal power plants and coal-fired thermal power plants may start giving priority to the
construction of LNG-fired thermal plants as part of an energy policy. If a grid-connected
renewable energy project is conducted in this sort of country, it is appropriate to consider
coal for the Build Margin.
3. Comments concerning Step 3
We believe that the concept of using a combined margin uniformly for all renewable
energy projects needs reconsideration.
At the very least, it is not appropriate to regard wind and solar sources as affecting the grid
build margin. They do not provide steady power generation, so although they enable a
reduction in grid-side generation (kWh), they do not enable generating capacity (kW) to be
eliminated.
Therefore, the combined margin approach should be varied according to the type of
renewable energy project. For instance, wind and solar sources could be handled as "wBM
＝0".
Furthermore, if appropriate dispatch data can be obtained in Step 1 c), that data can be used
here. In sum, it is not appropriate to use the combined margin. The appropriate approach is
"wBM＝0".
Comments on Consolidated Meth (grid renewable).doc: 04/06/30 20:00 2/2