It is clear that the Age of Oil is winding down. Worldwide, the rate of discovery of new oil reserves peaked in the 1960s and in the US our peak rate of oil discovery occurred in the early 1930s. In recent years the world has used about three barrels of oil for every barrel of new oil reserves discovered. Thus we are living largely on past oil discoveries. There is still a lot of oil in the world, and we will still be using a lot of oil decades from now. But it will be increasingly expensive both economically and environmentally to find, produce and refine that oil. Thus we need to identify and develop realistic petroleum alternatives.
The question is therefore: What are possible alternatives to oil? What criteria should guide us as we choose between possible alternatives? I suggest the following tentative set of metrics for choosing between our various alternatives to oil and I welcome discussion around this topic.
Metric #1: Scale Humankind currently uses about 450 exajoules (EJ) of energy per year and will require even more energy in the future. Petroleum provides about one third of global primary energy. As a starting point for discussion, let us require that any petroleum alternative be capable of providing roughly 10% of that currently provided by petroleum, or 15 EJ/year, if we are to take it seriously.
Metric #2: Cost of the fuel It seems highly unlikely that future transportation fuels will ever be as inexpensive as the fuels provided by oil at $20 per barrel. However, we cannot pay an unlimited amount for transportation fuels either. As a starting point for discussion, let us require that any oil replacement at technological maturity be capable of providing fuels at a cost equivalent to oil at about $100 per barrel, roughly the current level.
Metric #3: Capital cost of the fuel production system Many decades and trillions of dollars will be required to make the transition to petroleum alternatives. Thus lower capital cost systems providing the same energy output are obviously very highly favored as they will require less current wealth (foregone current consumption) invested to ensure future access to energy. Systems that use or leverage existing capital assets for raw material production, fuel processing and distribution are thus highly advantaged.
Metric #4: Energy Return on Energy Invested Society functions on the surplus energy (called “net energy”) provided by its fuel system that is in excess of the energy required to build, maintain and operate the fuel system. This simple physical fact is often expressed as a ratio called the “energy return on energy invested” or EROI. EROI is equal to the energy provided to society by the fuel production system divided by the energy input from society required to build and operate the fuel production system. I suggest a minimum EROI ought to be greater than 6:1, that is, 5 GJ of energy “surplus” to society for every 1 GJ used in the fuel production and distribution system.
Metric #5: Sustainability There seem to be four primary aspects of sustainability with regard to petroleum alternatives: economic viability (discussed above), environmental impacts, social impacts and renewability. I believe renewability is the key sustainability criterion. The next energy systems we put in place should, in principle, last indefinitely, not just the century or two that oil was able to serve humankind’s needs. Renewability is relatively easy to gauge whereas environmental impacts are less easy to gauge – such as greenhouse gas (GHG) emissions, water use and water quality effects, biodiversity, land use – and will probably differ for different fuels, different stakeholders and different situations.
I find this to be one of the most pressing issues we face, partially because the changes we need are so dramatic. It seems that a sub-text of Prof. Dale’s… Read more »
I agree that we need as much sustainable electricity as we can to support mobility, but it is simply not possible for electricity to meet all the work needs that… Read more »
I’m not quite sure the Age of Oil is winding down just yet, considering the recent shale oil boom and dramatic vehicle fuel economy improvements in the pipeline. In addition,… Read more »
Thank you for this comment. I do agree that we need to use as much of the existing fuel infrastructure as possible, and that fact is included in the last… Read more »
Thank you for the reaction to my comment, Dr. Dale, but it appears you and I differ in calling the existing fleet part of the fuel infrastructure. And I note… Read more »
Ellen, I have revised Metric #3 in the revised metrics to account for the fuel use (vehicle) phase of the system. It now reads: Metric #3: Capital cost of the fuel production… Read more »
Dr. Dale, I think your revised Metric 3 is much improved over the original, and it nicely covers the issue I raised. Thank you for reconsidering it. As for E30,… Read more »
Ellen, There is an implicit assumption that vehicles are hard coded for the fuel. This is NOT the case. The fuel is a programmable feature of the ECU. Similarly the… Read more »
Eyal, Cars have about 30,000 parts, and the US fleet contains about 250,000 vehicles of different designs and ages. It seems quite simplistic to say one only needs to tweak… Read more »
Ellen, My apologies, indeed my statement was over simplistic . You are right that cars are incredibly sophisticated machines which a large number of parts. However, inside the cars of interest are parts… Read more »
I think the criteria in the article is correct, but I believe the questions are rather moot. Any country must prepare itself for changes in access to and costs of… Read more »
I thank Mr. Sklar for emphasizing the importance of giving the consumer energy choices. I agree that fuel choice is crucial to proper market function. Unfortunately, the existing energy industry… Read more »
I don’t agree with this idea. National concerns are one thing, To assure reliable electricity to a nation’s populations requires a myriad of decisions, investments and regulatory negotiations. No simple… Read more »
Mr. Rossin, I don’t understand your comment. Would you like to clarify? I was not thinking primarily of electricity when I developed these metrics, but rather about liquid fuels.
This is not anything I follow but thought you all who do might not want to miss this info from NREL It says to me that we aren’t there yet.… Read more »
There are many developing alternative liquid fuels with respect to conventional oil which appear promising, but hard work lies ahead. Nevertheless, appropriate metrics represent an astute question at this time… Read more »
If we think about one example — biofuels — we can quickly identify the fact that each alternative has its own constraints. For biofuels, the constraint that matters is acres… Read more »
Carl, I really appreciate your comment. Your condensation of transportation biofuel considerations down to a metric of ton-mile/acre is really an expression of energy density. If we explicitly add in… Read more »
Mr. Pope, these are all important and relevant comments. I especially appreciate your emphasis on the system. We have not been very good at thinking about the energy system as… Read more »
Thanks Dr. Dale — the challenge is understanding the system well enough to do complete modelling — but we have to try.
Dale once again asserts a “peak oil” premise that others dispute. Putting that aside, it’s certain that at some point in the future, even if not imminently, petroleum will be… Read more »
I thank Dr. Perelman for his response. I agree that EROEI can be difficult to calculate, and it is also true that not all BTU are created equal. Well-executed EROEI… Read more »
Dr. Dale, Sorry to have to say that I cannot get past the errors in your premises. We have no shortage of petroleum based fuel. Please check out what is… Read more »
Jack, While your view is certainly the industry and government conventional wisdom, it is a very short term view that is fraught with significant under-reported uncertainties. We currently have only… Read more »
The Age of Oil is winding down but not for the reasons stated. The stated assumptions that the marginal barrel of oil is more expensive to produce and refine would… Read more »
Thank you, Dr. Rao. Conservation, substitution and efficiency improvements are certainly critical, and I do not wish to diminish their importance. But we are also going to have to deal… Read more »
Additional suggested metrics and modifications of my suggested metrics Timing I thank several commentators for mentioning the timing issue. I agree it is a key metric that I… Read more »
Employing metrics for evaluating the prospects and performance of global primary energy supplies and fuels has been the bread and butter of my recent years working as a military strategic… Read more »
IKE: I appreciate the hard work you have put into your comprehensive analysis but I must point out some basic errors in your presentation. For example, your statements in the… Read more »
Brian, Thank you for the close inspection of my post. 1. You are absolutely correct about 1.6 trillion instead of billion for proved crude oil reserves. What’s 3 orders of magnitude… Read more »
IKE: I did misinterpret your diagram on hydro EROI and I stand corrected. I’m glad we can at least agree that hydro is an important renewable energy with a high… Read more »
I think that one has to look at the final cost to the consumer. I would postulate (without proof) that there is “infinite” amount of oil at $1,000 a barrel. To… Read more »
Brian, I am very acquainted with Megan Guilford’s EROI paper. It offers a detailed look at oil and natural gas, but does not address any of the other energy sources… Read more »
Dear Colleagues: Thank you for your input on my initial proposed set of metrics. There was actually quite a lot of agreement about these metrics, which is gratifying. I have… Read more »
Bruce my friend, I have a request and couple of comments. My request is this. Can you produce the graph in your opening post but stated in total dollar expenditure… Read more »
Hello Eyal: I am afraid I don’t have the information needed to make that conversion for total dollars for each fuel by year, but I can give you some rough… Read more »