Paul Midford has clearly studied the renewables issue a lot more than I have. I'd have to see how experts would respond to his latest arguments about storage technology, etc.

In the meantime, I do what I usually do when I have no expertise of my own: rely on the consensus view of experts. As I first noted in a previous post, a 2010 report of the US National Academy of Sciences spoke of two major scientific/engineering barriers to predominant use of renewables. One is that lots of electricity is lost in transmission, a barrier to putting acres and acres of solar cells in the deserts, or wind farms in the seas, and transmitting the electricty to cities hundreds or thousands of miles away. Another is storage that can handle the loads required at a feasible cost, a problem easily seen in the difficulties of producing feasible storage batteries for cars. They wrote:

"The primary current barriers [to renewables] are the cost-competitiveness of the existing technologies .... the lack of sufficient transmission capacity to move electricity generated from renewable resources to distant demand centers, and the lack of sustained policies. Expanded research and development
(R&D) is needed to realize continued improvements and further cost reductions for these technologies....It is reasonable to envision that, collectively, non-hydropower renewable electricity could begin to provide a material contribution (i.e., reaching a level of 10 percent or more... in the period up to 2020 with such accelerated deployment....
It is reasonable to envision that continued and even further accelerated deployment could potentially result in nonhydroelectric renewables providing, collectively, 20 percent or more of domestic electricity generation by 2035....[this compares to DPJ goal of 20-27% non-hydro by 2030--rk]
Achieving a predominant (i.e., >50 percent) penetration of intermittent renewable resources such as wind and solar into the electricity marketplace, however, WILL REQUIRE TECHNOLOGIES THAT ARE LARGELY UNAVAILABLE OR
NOT YET DEVELOPED TODAY [emphasis added--rk] such
as large-scale and distributed
cost-effective ENERGY STORAGE and new methods for cost-effective, LONG-DISTANCE ELECTRICITY TRANSMISSION. ....
....Policy incentives, such as renewable portfolio standards, the production tax credit, feed-in tariffs, and greenhouse gas controls, thus have been required, and for the foreseeable future will continue to be required, to drive further increases in the use of renewable sources of electricity.....
Comparisons between past forecasts of renewable electricity penetration and actual data show that, while renewable technologies generally have met forecasts of cost reductions, THEY HAVE FALLEN SHORT OF DEPLOYMENT PROJECTIONS.... "

Since Paul reports on storage technologies that have been in use for years, and are presumably known to the NAS report authors in 2010, I have to presume that their assessment of these technologies is different from his. I'd be delighted if new developments come along that cause these experts to change their minds.

Richard Katz
The Oriental Economist