Editing Oil shale (section)

== Economics ==
{{PanoViewer|Oil shale - from research to reality 03. Enefit280 plant, view of the plant.jpg|360° panoramic view of a Enefit280 plant in [[Estonia]], that processes 280 tonnes of oil shale in an hour}}
{{Main|Oil shale economics}}
The various attempts to develop oil shale deposits have succeeded only when the cost of shale-oil production in a given region comes in below the price of crude oil or its other substitutes ([[Break-even (economics)|break-even price]]). According to a 2005 survey, conducted by the [[RAND Corporation]], the cost of producing a barrel of oil at a surface retorting complex in the United States (comprising a mine, retorting plant, [[upgrader|upgrading plant]], supporting utilities, and spent shale reclamation), would range between [[US dollars|US$]]70–95 ($440–600/m<sup>3</sup>, adjusted to 2005 values). This estimate considers varying levels of kerogen quality and extraction efficiency. In order to run a profitable operation, the price of crude oil would need to remain above these levels. The analysis also discussed the expectation that processing costs would drop after the establishment of the complex. The hypothetical unit would see a cost reduction of 35–70% after producing its first {{convert|500|Moilbbl|abbr=off}}. Assuming an increase in output of {{convert|25|koilbbl/d}} during each year after the start of commercial production, RAND predicted the costs would decline to $35–48 per barrel ($220–300/m<sup>3</sup>) within 12 years. After achieving the milestone of {{convert|1|Goilbbl|abbr=off}}, its costs would decline further to $30–40 per barrel ($190–250/m<sup>3</sup>).<ref name="eu">
{{cite report
 |publisher   = European Academies Science Advisory Council
 |url         = https://www.easac.org/fileadmin/PDF_s/reports_statements/Study.pdf
 |title       = A study on the EU oil shale industry viewed in the light of the Estonian experience. A report by EASAC to the Committee on Industry, Research and Energy of the European Parliament
 |last1       = Francu
 |first1      = Juraj
 |last2       = Harvie
 |first2      = Barbra
 |last3       = Laenen
 |first3      = Ben
 |last4       = Siirde
 |first4      = Andres
 |last5       = Veiderma
 |first5      = Mihkel
 |pages       = 12–13; 18–19; 23–24; 28
 |date        = May 2007
 |access-date  = 21 June 2010
 |url-status  = dead
 |archive-url  = https://web.archive.org/web/20110726011345/http://www.easac.org/fileadmin/PDF_s/reports_statements/Study.pdf
 |archive-date = 26 July 2011
 |df          = dmy-all
}}
</ref><ref name="rand" /> In 2010, the [[International Energy Agency]] estimated, based on the various pilot projects, that investment and operating costs would be similar to those of [[Athabasca oil sands|Canadian oil sands]], that means would be economic at prices above $60 per barrel at current costs.  This figure does not account [[carbon pricing]], which will add additional cost.<ref name="weo2010 165" /> According to the New Policies Scenario introduced in its [[World Energy Outlook|World Energy Outlook 2010]], a price of $50 per tonne of emitted {{CO2}} adds additional $7.50 cost per barrel of shale oil.<ref name="weo2010 165" /> As of November 2021, the price of tonne of {{CO2}} exceeded $60.

A 1972 publication in the journal ''Pétrole Informations'' ({{ISSN|0755-561X}}) compared shale-based oil production unfavorably with [[coal liquefaction]]. The article portrayed coal liquefaction as less expensive, generating more oil, and creating fewer environmental impacts than extraction from oil shale. It cited a conversion ratio of {{convert|650|L|U.S.gal impgal}} of oil per one [[ton]] of coal, as against {{convert|150|L|U.S.gal impgal}} of shale oil per one ton of oil shale.<ref name="laherrere" />

A critical measure of the viability of oil shale as an energy source lies in the ratio of the energy produced by the shale to the energy used in its mining and processing, a ratio known as "[[energy return on investment]]" (EROI). A 1984 study estimated the EROI of the various known oil-shale deposits as varying between 0.7–13.3,<ref name="science2">
{{Cite journal
 | last1 = Cleveland | first1 = Cutler J.
 | last2 = Costanza | first2 = Robert
 | last3 = Hall | first3 = Charles A. S.
 | last4 = Kaufmann | first4 = Robert
 | title =Energy and the U.S. Economy: A Biophysical Perspective
 | journal = [[Science (journal)|Science]]
 | publisher = [[American Association for the Advancement of Science]]
 | volume = 225
 | issue = 4665
 | pages =890–897
 | date = 31 August 1984
 | issn = 0036-8075
 | doi =10.1126/science.225.4665.890
 | pmid =17779848|bibcode = 1984Sci...225..890C | s2cid = 2875906
 }}
</ref> although known oil-shale extraction development projects assert an EROI between 3 and 10.  According to the World Energy Outlook 2010, the EROI of ''ex-situ'' processing is typically 4 to 5 while of ''in-situ'' processing it may be even as low as 2. However, according to the IEA most of used energy can be provided by burning the spent shale or oil-shale gas.<ref name="weo2010 165"/> To increase efficiency when retorting oil shale, researchers have proposed and tested several co-pyrolysis processes.<ref name="co-pyrolisis2">
{{Cite journal
 | title =Fixation of chlorine evolved in pyrolysis of PVC waste by Estonian oil shales
 | last1 = Tiikma | first1=Laine
 | last2 = Johannes | first2=Ille
 | last3 = Luik | first3=Hans
 | journal=Journal of Analytical and Applied Pyrolysis
 | date=March 2006
 | volume=75
 | issue=2
 | pages=205–210
 | doi =10.1016/j.jaap.2005.06.001}}
</ref><ref name="veski1">
{{Cite journal
 | last1 =Veski | first1 =R.
 | last2 =Palu | first2 =V.
 | last3 =Kruusement | first3 =K.
 | title =Co-liquefaction of kukersite oil shale and pine wood in supercritical water
 | journal = [[Oil Shale (journal)|Oil Shale. A Scientific-Technical Journal]]
 | publisher = Estonian Academy Publishers
 | volume =23
 | issue =3
 | pages =236–248
 | year =2006
 | doi =10.3176/oil.2006.3.04
 | s2cid =59478829
 | url=http://www.kirj.ee/public/oilshale/oil-2006-3-4.pdf
 | issn = 0208-189X
 | access-date =16 June 2007}}
</ref><ref name="Morocco">
{{Cite journal
 | last1 = Aboulkas | first1 =A.
 | last2 =El Harfi | first2 =K.
 | last3 =El Bouadili | first3 =A.
 | last4 =Benchanaa | first4 =M.
 | last5 =Mokhlisse | first5 =A.
 | last6 =Outzourit | first6 =A.
 | title = Kinetics of co-pyrolysis of Tarfaya (Morocco) oil shale with high-density polyethylene
 | journal = [[Oil Shale (journal)|Oil Shale. A Scientific-Technical Journal]]
 | publisher = Estonian Academy Publishers
 | volume =24
 | issue =1
 | pages =15–33
 | year =2007
 | doi =10.3176/oil.2007.1.04
 | s2cid =55932225
 | url=http://www.kirj.ee/public/oilshale/oil-2006-3-4.pdf
 | issn = 0208-189X
 | access-date =16 June 2007}}
</ref>