The Shape of Net Zero (1): No Substitute

Oil an irreplaceable energy source

As good as it gets

This is the first article in a series to do the future of energy in a Net Zero world. In this article we look at fossil fuels, why they are so valuable, and the properties they have that will make them so difficult to replace.

Many of the discussions in this series are based on the following sketch. We will review and analyze sections of this sketch in future discussions. For this article, the circle labeled ‘Crude Oil’ at the bottom, left-hand corner of the sketch is the topic of discussion. We look at some of the features of fossil fuels, particularly oil, that make them so difficult to replace. None of the alternative sources of energy provide such an ideal mix of properties. For example, wind and solar have no direct emissions, but they are intermittent. 

No replacement for fossil fuels and oil
Credit: Sutton Technical Books

At the heart of virtually all discussions to do with climate change lies the following question,

Are there any alternative sources of energy that will allow us to maintain our current material standard of living while not causing increased global warming?

As we will see in subsequent articles, the hard truth is that none of the alternative sources such as solar, wind or nuclear possess attributes that allow us to answer the above question with an unqualified “Yes”.

When a new source of energy is proposed it can evaluated according to the following parameters.

  • Economical / Cost Effective
  • Safe
  • Environmentally clean (as distinct from global warming)
  • Energy Density
  • Availability
  • Portable
  • Chemical Feedstock
  • Renewable

The following Table evaluates the principal fossil fuels — coal, oil and natural gas — with respect to the above criteria.  (The same Table will be used in future articles to evaluate the effectiveness of alternative sources of energy.)

The letters have the following meaning:

  • “Y” means Yes — the fuel meets that criterion.
  • “N” means No — the fuel is not a good choice.
  • “P” means Partially Acceptable 

Features of Fossil Fuels

Features of Fossil Fuels
Credit: Sutton Technical Books

Economical
The cost of an energy source includes not just the direct purchase cost but also indirect and hidden costs (such as the need to provide backup power). In general, fossil fuels are economically attractive and more cost effective than their proposed replacements.

Safe
All types of energy source have the potential to be unsafe if they are handled in an uncontrolled manner.  Fossil fuels are generally safe, and we have accumulated a lot of knowledge and experience to do with their safe handling.

Environmental
This category considers the environmental impact of an energy source other than greenhouse gas emissions. Nuclear fission, for example, creates radioactive waste that has to be stored in a secure location for centuries. In general fossil fuels are environmentally clean. Coal has been given a ‘N’ due to problems to do with disposal of the ash that is left behind after it is burned. Overall, the environmental impact of fossil fuels is manageable.

Energy Density
One of the most important features of fossil fuels, particularly oil, is that they are “energy dense” — they provide a large amount of energy from a small supply of the fuel. Few other energy sources can come close. (The Table shows that oil typically has twice the energy density of coal.)

Always Available / Dispatchable
One of the least appreciated features of fossil fuels is that they are always available, i.e., they are dispatchable. The importance of this feature is explained in the second article in this series, The Shape of Net Zero: Alternative Energy Sources. Suffice to say that they can be turned on or off, up or down, at very short notice. Such is not the case with many alternative energy sources, particularly solar and wind.

Portable
Fossil fuels are portable — they do not have to be converted to electricity before they can be transferred to another location.  and can be used directly. There is no need to have a physical infrastructure for their transportation. This is not the case for most other energy sources — they generate electricity which has to be moved along a grid to the end user. This feature is particularly important with respect to transportation. (Natural gas is given a ‘P’ because, although it can be moved from one place to another, it can be difficult and expensive to transport. It needs either a large pipeline with associated compressors, or it has to be liquefied, transported and then regasified at its final destination.)

Chemical Feedstock
Between 10 and 15% of a barrel of oil provides feedstocks to the petrochemical industry. There the thousands of products, ranging from fertilizers to plastics to medicines, that provide the foundation of modern life, are manufactured. There is no viable alternative to fossil fuels in this area. Which begs the question as to how oil refineries are to be run if 90% of their products are not needed any more.

Renewable
This is the one area where fossil fuels have a major drawback: fossil fuels are not renewable on a human time scale. Others, such as wind and solar are not finite, they cannot be depleted.

GHG Emissions
Some energy sources emit greenhouse gases (GHG), thus leading to global warming. All fossil fuels fall into the ‘N’ category for this item. Other energy sources, such as wind and solar, have no emissions, which is why they are so attractive in a Net Zero environment.

Replacement Potential
It is useful to have some estimate, no matter how rough, as to what impact an alternative energy source might have were it to be applied as widely as possible. What percentage of the world’s demand for energy could it supply? Such an estimate is necessarily very, very approximate. Nevertheless, it does provide some insight as to what the overall impact of the alternative energy may be. In the Table this column is blank since it is fossil fuels that are being replaced.

In summary, the Table shows why fossil fuels are so attractive. Nevertheless, the drawbacks of fossil fuels — the fact that they are non-renewable and that they create greenhouse gases — are so serious that they must be replaced as soon as possible.

No Suitable Replacement

It is misleading to think that we can simply swap out one source of energy for another. Every energy source has its strengths and weaknesses, but none of them have the mix provided by fossil fuels, particularly crude oil.  This means that not only is there a direct cost associated with switching to alternative energy sources, there will always be a background cost to do with running society on energy that is less effective than the fossil fuels.


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