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Response to ‘‘A critique of Jacobson and Delucchi’s proposals for a world
renewable energy supply’’ by Ted Trainer
Mark A. Delucchi
a,
n
, Mark Z. Jacobson
b
a
Institute of Transportation Studies, University of California at Davis, Davis, CA 95616, USA
b
Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305-4020, USA
article info
Article history:
Received 24 October 2011
Accepted 28 October 2011
Available online 17 November 2011
Keywords:
Renewable energy
Wind water
Solar power
Ted Trainer’s ‘‘A critique of Jacobson and Delucchi’s proposals for a
world renewable energy supply’’ (hereafter T11), directed at our two
Energy Policy articles ‘‘Providing all global energy with wind, water,
and solar power, Part I: Technologies, energy resources, quantities
and areas of infrastructure, and materials’’ (hereafter JD11) and
‘‘Providing all global energy with wind, water, and solar power,
Part II: Reliability, system and transmission costs, and policies’’
(hereafter DJ11), makes two main points:
(1) that JD11 and DJ11 do ‘‘not deal effectively with the problems
set by the variability of renewable energy sources,’’ and
(2) that the JD11/DJ11 ‘‘analysis of investment costs is inadequate.’’
Neither of these criticisms is valid. We show here that T11’s
first main point is based on a misrepresentation of what is stated
and referenced in DJ11, and that his second main point is based
on mistakes and unreasonable assumptions. As a result, T11’s
critique does not affect our original analyses or our conclusion
that it is technically, economically, and environmentally feasible
to provide all global energy with wind, water, and solar power.
We organize our response around T11’s two main criticisms
(variability and investment costs) and under each main criticism
by T11’s topic headings.
1. Variability
1.1. Magnitude of the variability problem
Most of this background information in T11 is well known and
either is not specifically relevant to JD11/DJ11 or else is addressed
in those papers. However, this section of T11 also contains an
important error. T11 states:
‘‘Jacobson and Delucchi expect 50% of energy to come from
wind. Again no attempt is made to explain where energy is
supposed to come from during the kinds of weather events
described above which can last for several consecutive days.’’
This statement is incorrect. Section 1.2 of DJ11 addresses the
issue:
‘‘The figure (Figure 1) illustrates the potential for matching
power demand hour by hour based on a Monte Carlo simula-
tion that accounts for the stochastic nature of each resource
(20 potential realizations each hour). Although results for only
two days are shown, results for all hours of all days of both
2005 and 2006 (730 day total) suggest that 99.8% of delivered
energy during these days could be produced from WWS
technology. For these scenarios, natural gas was held as
reserve backup and supplied energy for the few remaining
hours. However, it is expected that natural gas reserves can be
eliminated with the use of demand–response measures, sto-
rage beyond SP, electric vehicle charging and management,
and increases in wind and solar capacities beyond the inflex-
ible power demand, which would also allow the excess energy
to produce hydrogen for commercial processes, thereby redu-
cing emissions from another sector.’’
The reference for this result is provided as Hart and Jacobson
(2011a), which was in review at the time, but a website was given
for a copy of the paper. The paper has now been published. This
analysis accounted for all anomalous weather conditions in
California (e.g., consecutive days without wind or solar), which
are similar to those anywhere in the world. It demonstrated that
Contents lists available at SciVerse ScienceDirect
journal homepage: www.elsevier.com/locate/enpol
Energy Policy
0301-4215/$ - see front matter & 2011 Elsevier Ltd. All rights reserved.
doi:10.1016/j.enpol.2011.10.058
n
Corresponding author. Tel.: þ1 916 989 5556; fax: þ1 916 989 5566.
E-mail address: madelucchi@ucdavis.edu (M.A. Delucchi).
Energy Policy 44 (2012) 482–484