I don't believe he was actually asking for information; so I was addressing what I believe to be the true message in his communication.
Second; I'm familiar with Cavallo and DeCarolis because I'm from the "more-academic" side of the picture.
The DOE paper is a good one and it presents an excellent meta-analysis of the available data. What it lacks is outlined clearly in the conclusion and readers should heed those limits as more than boilerplate warnings - I've underlined the section. The academic side of the picture is (to use their expression) "arguably" more informative at this point than what can be produced by their "bottom up" approach. As more concrete data develops and as policy options clarify and shape the business environment, studies of this nature will become much more predictive of what can be expected both in costs and need.
Since the paper you offered covers that aspect well, recommending the "rest of the story" seemed appropriate.
Finally, it's worth pointing out that Cavallo is the "father" of advocating for the idea that it would be cost effective to provide "baseload" power from large scale wind transmitted over long distances. At the time, the "less academic" community was absolutely sure that 1) more than 5% penetration by wind would be death to the reliability of the grid (those voices are now totally silent). And 2) such transmission would be death to the economics of wind at any scale.
You can see from the conclusion whose analysis carried the day.
Conclusions
Recent growth in wind power development in the United States has been coupled with a growing concern that this development will require substantial additions to the nation’s transmission infrastructure. It is clear that institutional issues related to transmission planning, siting, and cost allocation will pose major obstacles to accelerated wind power deployment, but also of concern is the potential cost of this transmission infrastructure build out.
In this report, we have reviewed a sample of 40 regional transmission studies that have included wind power. These studies vary considerably in scope, authorship, objectives, and methodology, making comparisons difficult.
Regardless, our analysis of these studies reveals considerable differences in the implied unit cost of transmission for wind. In particular, the total range in unit transmission costs for wind implicit in these studies is from $0/kW to over $1,500/kW, though some of this range is surely the result of flaws in our methodological approach.
The majority of studies in our sample, however, have a unit cost of transmission that is below $500/kW, or roughly 25% of the current $2,000/kW capital cost of building a wind project. The median cost of transmission across all scenarios in our sample is $300/kW, on a capacity-weighted basis; roughly 15% of the current cost of building a wind project or 23% of the cost of building a wind project in the early 2000s. In terms of cost per megawatt-hour of wind power generation, the median cost is $15/MWh on a capacity-weighted basis, and most studies fall below $25/MWh.
Two highly-conceptual, top-down studies of 20% wind power penetration in the U.S. electricity system have implied unit costs of transmission below or nearly equivalent to the median cost of our sample of 40 bottom up transmission planning studies.
These mid-range costs, though not insignificant, are also not overwhelming. Additionally, the limitations of our methodology likely err towards an over-statement of the unit cost of transmission for wind.
The need for transmission expansion, for example, is not unique to wind: other generation sources will also require transmission expenditures. Transmission expansion also typically serves multiple purposes, and our approach to assigning the full costs of that expansion to generation capacity additions effectively ignores those other benefits.
And, in at least some of the studies in our sample, transmission is oversized, leading to an over-estimate of the transmission costs uniquely associated with wind additions.
Finally, in taking a deliverability (rather than congestion) focus, a number of the studies in our sample reflect existing contractual limits that, if overcome, could increase the efficiency of grid operations and lower the unit cost of transmission for wind; further work on this specific issue is merited.
Because the range of transmission costs surveyed here is broad, however, with a number of high-cost scenarios, it is also important to understand how differences in study objectives, methodologies, and assumptions can impact the resulting cost estimates.
Our work has only begun that process, and far more comparative work is needed.
Transmission costs do appear to be high in cases where long transmission lines are added without accessing substantial amounts of new generation. At the same time, we find little evidence that higher levels of wind penetration require dramatically increased unit transmission costs, relative to more-moderate levels of wind deployment.
This seems to be confirmed by two top down scenarios of 20% wind energy in the U.S., the JCSP study of 20% wind energy in the Eastern Interconnection, and by a number of bottom up study scenarios that add greater than 10 GW of new generation. It therefore appears that the unit cost of transmission for wind need not increase dramatically at higher levels of wind penetration.