![]() | An Interview with Trilby Lundberg (or, Prof. Goose May Have a New Sworn Enemy) | The Oil Drum | DrumBeat: July 12, 2007 | ![]() |
![]() | UK Parliamentary Group on Peak Oil and Gas Formed | The Oil Drum: Europe | IEA boss denies and confirms peak oil in same breath | ![]() |
Blogroll
- ASPO The official site of the Association for the Study of Peak Oil & Gas.
- Energy Bulletin Clearing house for news regarding the peak in global energy supply.
- PowerSwitch Dedicated to raising awareness & discussion of the impending & permanent decline of cheap oil & gas supply.
- ODAC Oil Depletion Analysis Centre working to raise awareness and promote better understanding of the world's oil-depletion problem.
- Global Public Media Public service broadcasting for a post carbon world.
- Post Carbon Institute Learning to live in a low energy world.
- PeakOil.com US site and forum to educate and promote awareness of global hydrocarbon depletion.
- FEASTA The Foundation for the Economics of Sustainability
- Tradable Energy Quotas (TEQs) This website describes an effective and fair response both to climate change and oil/gas depletion
Other Blogs
User login
Personnel
Editors
Contributors
Peak Oil Primers
Archives
- August 2008
- July 2008
- June 2008
- May 2008
- April 2008
- March 2008
- February 2008
- January 2008
- December 2007
- November 2007
- October 2007
- September 2007
- August 2007
- July 2007
- June 2007
- May 2007
- April 2007
- March 2007
- February 2007
- January 2007
- December 2006
- November 2006
- October 2006
- September 2006
- August 2006
- July 2006
- June 2006
- May 2006
- April 2006
- March 2006
Vital Trivia
License
This work is licensed under a Creative Commons Attribution-Share Alike 3.0 United States License.





GAIA Host Collective
Surely if the energy ROI is positive, then so would be the financial ROI?
Apologies, I haven't thoroughly read all of the reports, I was wondering if there was a quick answer to the question that the peak oil skeptics like to use - i.e. 'It's not economic at the moment'
For some production scale, yes.
But the minimum scale depends on salaries, non-energetic inputs, interest and ERoEI. And the dependence on ERoEI grows very fast when ERoEI approaches 1.
Surely if the energy ROI is positive, then so would be the financial ROI?
There is a lot of overlap, but it's not 1:1. For example, if you are producing gas from a well but don't have infrastructure to deliver it to a market, the gas is flared. Therefore it may have a high EROEI, but would have poor ROI.
Conversely, if you can use the gas to turn tar sand into syncrude, which can be more easily transported to a market, then the tar sand has a positive ROI even if it has a poor EROEI.
In general though, a back of the envelope formula is
C = nP + F
where C is the cost of producing a barrel of oil equivalent, n is the number of BOE used, P is the price per BOE, and F is non-energy (fixed) cost.
then the required price for break-even is:
P = F / (1-n)
Here I have assumed that the non-energy costs are fixed, which may not be the case. In practice, these costs may also rise, e.g. rising cost of steel.
Note this equation incorporates EROEI.
To illustrate how this works, an example. With an oil price of $40/bbl, I estimate that my turkey offal syncrude costs $80/bbl to produce. At what oil price do I break-even? The answer is not $80/bbl. Of my costs, let's say $20 is direct energy cost, and $60 are fixed costs (plant etc). Therefore
P = $60 / (1-0.5) = $120
In this example the EROEI was 2:1. As EROEI decreases, the break even price increases.
I see you are saying n = 1/EROEI so that 0.5 = 1/(2). This works for fuels not wind and solar where depreciation has to be converted to energy equivalents, with interest being a somewhat fixed cost. In the case of corn ethanol (say EROEI = 1.25, n = 0.8) the sale price in effect gets an add-on from the tax credit.
I think mechanised coal mining will stop when it gets into the EROEI range of 2 to 4. Gubmints just won't have the revenue to subsidise it.