The seemingly most reliable information on EROI is quite old and is summarized in chapter 12 of Hall et al. (1986). Newer information tends to fall into the wildly optimistic camp (high EROI, e.g. 10:1 or more, sometimes wildly more) or the extremely pessimistic (low or even negative EROI) camp (Tyner et al. 1998, Tyner 2002, Fleay 2006 and Caldicamp 2006). One recent PhD analysis from Sweden undertook an emergy analysis (a kind of comprehensive energy analysis including all environmental inputs and quality corrections as per Howard Odum) and found an emergy return on emergy invested of 11:1 (with a high quality factor for electricity) but it was not possible to undertake an energy analysis from the data presented (Kindburg, 2007). Nevertheless that final number is similar to many of the older analyses when a quality correction is included.
Figure 9. EROI for nuclear power plotted vs. year of analysis. (Source Robert Powers).
Click to Enlarge.
Tyner was the author (or co-author) on the 1988 and 1997 reports which are examples of the lower EROI numbers -- less than 5:1. Tyner’s 1997 paper reported an “optimistic value” of 3.84 and a “less-optimistic” value of 1.86 and may be based on “pessimistic” cost estimates.
Energy Net on 29 Nov 08Earth2Tech reports that England may be left out of Scottish plans to join a European supergrid crossing the north sea - Scotland Snubbing England in Supergrid Plans?. The Scottish government believes the North Sea could become host to an underwater renewable energy grid, supplying power from wind, wave and tidal power across Europe, but England could be left out in the cold. A new study from Scotland looks at the possibility of a supergrid between Scotland, Norway, Sweden, Denmark, Germany and the Netherlands, but doesn't mention Scotland's big neighbor to the south. Yes, Scotland is still part of the UK, and most of England's east coast is also on the North Sea, but the word "England" doesn't even show up once in the 21-page study and "UK" is only used in a couple of footnotes. It might just be an oversight, but the possible snub comes during the same week in which the UK government made a filing with the Commission on Scottish Devolution questioning the Scottish government's powers covering energy.