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Title: Energy Return on Energy Invested (ERoEI) for photovoltaic solar systems in regions of moderate insolation: A comprehensive response

A recent paper by Ferroni and Hopkirk (2016) asserts that the ERoEI (also referred to as EROI) of photovoltaic (PV) systems is so low that they actually act as net energy sinks, rather than delivering energy to society. Such claim, if accurate, would call into question many energy investment decisions. In the same paper, a comparison is also drawn between PV and nuclear electricity. We have carefully analysed this paper, and found methodological inconsistencies and calculation errors that, in combination, render its conclusions not scientifically sound. Ferroni and Hopkirk adopt 'extended' boundaries for their analysis of PV without acknowledging that such choice of boundaries makes their results incompatible with those for all other technologies that have been analysed using more conventional boundaries, including nuclear energy with which the authors engage in multiple inconsistent comparisons. In addition, they use out-dated information, make invalid assumptions on PV specifications and other key parameters, and conduct calculation errors, including double counting. Here in this paper, we provide revised EROI calculations for PV electricity in Switzerland, adopting both conventional and 'extended' system boundaries, to contrast with their results, which points to an order-of-magnitude underestimate of the EROI of PV in Switzerland by Ferroni and Hopkirk.
 [1] ;  [2] ;  [3] ;  [4] ;  [5] ;  [6] ;  [7] ;  [8] ;  [9] ;  [10] ;  [11] ;  [12] ;  [13] ;  [14] ;  [15] ;  [16] ;  [17] ;  [15] ;  [18] ;  [19] more »;  [20] ;  [5] « less
  1. Oxford Brookes Univ. (United Kingdom); Columbia Univ., New York, NY (United States)
  2. Masdar Inst., Abu Dhabi (United Arab Emirates)
  3. St. Lawrence Univ., Canton, NY (United States)
  4. Columbia Univ., New York, NY (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)
  5. Treeze, Uster (Switzerland)
  6. Lappeenranta Univ. of Technology (Finland)
  7. Univ. of Florence (Italy)
  8. Western Washington Univ., Bellingham, WA (United States). Huxley College of the Environment and Inst. for Energy Studies
  9. Univ. of Sheffield (United Kingdom)
  10. Clemson Univ., SC (United States)
  11. Lancaster Univ. (United Kingdom)
  12. SmartGreenScans, Groet (The Netherlands)
  13. National Renewable Energy Lab. (NREL), Golden, CO (United States); Univ. of Colorado, Boulder, CO (United States)
  14. European Commission Joint Research Centre (JRC), Brussels (Belgium)
  15. Univ. of Manchester (United Kingdom)
  16. Nouvelle Donne, Paris (France)
  17. Parthenope Univ. of Naples (Italy)
  18. Northumbria Univ., Newcastle upon Tyne (United Kingdom)
  19. Insight Through Analysis, Washington, DC (United States)
  20. Univ. of Amsterdam (Netherlands)
Publication Date:
Report Number(s):
Journal ID: ISSN 0301-4215
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Energy Policy
Additional Journal Information:
Journal Volume: 102; Journal Issue: C; Journal ID: ISSN 0301-4215
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
Country of Publication:
United States
14 SOLAR ENERGY; 29 ENERGY PLANNING, POLICY, AND ECONOMY; EROI; ERoEI; photovoltaic energy; insolation levels; Switzerland; Germany; incentive system; adjustment factor
OSTI Identifier: