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Approach also ignores sprawl effect of non-dispatchability

Posted by EnvManager on 02 Oct 2009 at 19:17 GMT

Our approach ignores

The electric generation plant build level is determined by peak demand. Non-dispatchable sources of electricity (generally wind and solar) cannot be relied upon during peaks. For example, I believe during the 2009 MISO summer peak, wind contributed 1.29% of its rated capacity, or 66 out of 5,100 MWs. That is, more than 98% of the energy capacity was not available and had to be supplied by other dispatchable sources. Therefore, for every MW of non-dispatchable energy, a dispatchable source must also be constructed. Your approach ignores the energy sprawl of this additional dispatchable generation.

Competing interests declared: I am a power industry consultant, with current clients including natural gas, coal, waste coal, and biomass fueled generation; in my past clients, employers and regulated entities have generated electricity with all of these plus hydro, nuclear, wind and solar.

RE: Approach also ignores sprawl effect of non-dispatchability

rimcdonald replied to EnvManager on 03 Oct 2009 at 16:35 GMT

Actually, we do account for this issue. The EIA analyses on which we base our work incorporate the nameplate capacity factors you mention. So things like wind and solar need more nameplate capacity for a given amount of electricity, and hence take more space in our analysis.

Competing interests declared: .No competing interests, except I am the author of the paper:

RE: RE: Approach also ignores sprawl effect of non-dispatchability

rimcdonald replied to rimcdonald on 07 Oct 2009 at 18:12 GMT

Addendum to my comments above: while the data built upon the EIA analysis incorporates this nameplate capacity factor effect, our figure showing the various land-use intensity of production figures does not. This was a concious choice on our part, since similar concerns also exist for energy lost in the internal combustion engine, etc. So for that figure you should interpret it as the amount of land it takes to produce a certain amount of nameplate capacity (or a barrel of oil, etc) rather than the actual capacity (or the energy in a barrel of oil that is actually used for productive work, etc.)
Let me know if that does not make sense.

No competing interests declared.