Biofuels. An Overview.

Biofuels

An Overview

Ian J. Miller

Smashwords Edition

Copyright 2014 by Ian Miller. All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means without written permission from the author, except for fair use, including quotes for a review or a technical article, and with proper acknowledgement of the source.

Foreword

Our society runs on oil; if the supply of oil products were removed, modern civilization would have extreme difficulty in continuing in a way remotely like the way it is now. Oil production will not simply cease, but mathematics tells us that supply will decay over a period of time. Critical to our ability to maintain our society is how long this period is. If we have time, we can simply replace oil as the basis of our transportation system with something else. The purpose of this book is to show what the opportunities and difficulties are if that substitute is to be fully or partially filled by biofuels.

For a democracy to work, the general population should understand the essence of the problems society faces. Unfortunately, as technology continues to become a more significant part of our lives, those who have a very limited, or even worse, no grasp of science and technology do not participate properly. It is not possible for the average citizen to fully understand the details of every given technical issue, nevertheless with a little help they can understand when they are hearing a clear perspective or when they are being led down a path that could go anywhere. What the general population needs is an account that puts the issues into some sort of perspective so they can decide whether it is reasonable to invest their own money or to spend tax dollars in a given area, and whether without certain evidence to the contrary, other areas are simply not worth supporting at this time. The general population cannot be expected to understand the details, but it is helpful if they can at least approach some sort of understanding of the generalities of the problem.

Professional investors who wish to do something with their money for the good of society need something more detailed. They know there are risks, but they need to be able to put some scale on the risk, to be sure whether a given project lies inside or outside their comfort zone. Such investment decisions tend to be made on the basis of comfort with the persons involved, but some feeling for the technology is also required because it is unfortunate that the best presenters do not necessarily have the best technology.

Members of government fund allocation committees have to decide where public money should be spent, and they too need to understand what is involved, but unlike professional investors, they have to judge not what might lead to a company float in five years but rather what are the true fundamental constraints, i.e. what will not work in the long run, and what might be an eventual solution if only we knew X, Y and Z.

There are also people who can in principle understand the science, but they do not have the specific expertise or experience in the area. What they need is an overview with enough detail to form a sufficiently informed view that they can act as intermediaries between the specialist and the general public.

It is probably not possible to satisfy all of those objectives, and there is the danger that in trying to do so I shall satisfy nobody, nevertheless, I shall try with the issue of biofuels.

Why are biofuels important? That is, initially, the wrong question. A better question is, what will happen to society if we cannot power a transport system sufficiently well that the activities we carry out now are no longer possible. Some activities can be avoided. Thus I often go some distance to scientific meetings. In principle, technology could make such meetings available over the web, and progress is being made on that front right now, however the one thing that web meetings cannot do is to match the personal touch. Do we want to be a hermit culture? Unfortunately, our society has constructed cities that cover huge areas on the assumption that transport will always be cheap. As oil runs down, fuel will no longer be cheap, and it may not be available. However, while social contact can, in principle, be put to one side, getting to work cannot, and even more importantly, bringing food and other goods to the population most certainly must be addressed. Irrespective of what happens, we need a transport system.

Unfortunately, on the issue of how we power our future transport systems, the short answer is, nobody knows. There are no experts that can answer that question because, as I hope to show in this book, there are simply insufficient data. That does not mean that there is not a lot of arm waving and assurances from all and sundry that everything will be fine and technology will solve all our problems. There are very big differences between might if all goes well, could in principle, can, and will. If you want one message from this book, that should be that we need to carefully examine all our options, clarify exactly what we know and what we do not know, and work out a program to move issues from the do not know category into the know category.

There are two issues regarding oil replacement: what can be done, and how can it be done? The first relates to available technology, and that is the major issue covered by this book. These issues involve what processes are available, what processes are potentially available, and what constraints are there on those processes. As will be shown in this book, many of these questions cannot as yet be answered; nevertheless some can be answered in a very approximate way. For example, we might say we need more land area to grow biomass to convert to biofuels. One of the constraints is that the land has to be suitable, and we might exclude the Antarctic continent from consideration. It has plenty of land, but it is unsuitable for growing plants. Such approximate analyses give us guidelines as to what is possible; nevertheless as I shall say repeatedly, a considerable amount of further work remains to be done.

How we get it done is another question, and while I believe I know a reasonable amount about the technology, the how to do it is another problem altogether. There are two types of development: the enlargement of an existing technology, and this depends largely on whether there is a market. Ethanol substitution into petrol is one such example. We know how to make ethanol from fermentation, and the demand for fuel for a spark ignition engine is huge. By the same token, the oil industry supplies huge volumes of petrol at a price that alternative fuels have difficulty in matching. Such price issues have been matched by governments offering subsidies. However, one thing is clear: such subsidies only assist existing technologies, because they are the only ones that can take advantage of them.

These subsidies are to encourage alternatives, and are often made for strategic reasons, and there are varying views as to the validity of this approach. The strategic reasons can sometimes seem very valid, thus when the first oil crisis struck, in New Zealand oil supply was heavily constrained. A number of alternative technologies quickly emerged. These included the introduction of methanol/petrol blends, and the use of compressed natural gas and liquefied natural gas. Rather interestingly, after the oil price fell away, as the older vehicles were scrapped the outlets providing the alternative fuels also closed, and consequently such alternatives faded away. The exceptions included taxis and delivery vehicles that frequently returned to base, some of which retained the use of the gases.

The other type of alternative technology is novel, which means it is as yet not fully developed. These technology developments are driven by a risk/benefit analysis, and again there are two risks: technology and market risk. Investors tend to hate technology risk except, oddly enough, some who really do not understand the risk. Investors do not like market risk either, but it is one that they better understand. This leads to investors being more willing to back an ethanol venture than something that in the long run will be more useful. The other characteristic of the private investor is that the first thing they seek is a way out, a parachute, if you like.

You may think that venture capitalists will support new technologies, however they too do not like a long development time, and unfortunately in the chemical industries, timelines are very long for the introduction of new technologies.

One thing this book will not do is to show how to get things done. This is a matter of opinion. The market approach is to let the market take its way, which will probably lead to a crash, and then something will sort itself out. The market cares not for how many people get hurt in such a crash. You may think that nobody wants a crash, but that is not exactly correct. The reasonably clever and really rich do very well out of financial crashes. Perhaps governments should take up the slack in such an important strategic issue? That becomes a political issue, and that shall be left from this book. Where this leaves us is that this book will focus mainly on the technical issues, leaving the reader to deal with the political ones. The book is aimed to inform those who feel something should be done so that the right things can be done.

Thus the purpose of this book is now to outline some of the issues relating to biofuels for the general reader. The underlying problem with such an objective is where to draw the line relating to the underlying science, and in particular the chemistry. Half of me says, leave the chemistry aside because most readers will not be interested, but the problem with that is the reader then has to accept a number of assertions essentially on faith. If I make some chemical statement such as, If A and B react under conditions C, then we get products P and Q, and if I show why such a relationship should arise and why I think it is relevant, even if the reader does not really understand chemistry, (s)he will at least know there are reasons underpinning the statements. If the reader can see some sort of relationship between such statements, even if they do not fully understand what has happened in getting to them, perhaps the arguments will be easier to follow, or perhaps be more convincing.

For those with no chemical knowledge, my general advice is, do not worry; just gloss over the chemistry and accept there are relationships, then ask yourself why I am mentioning what is there (and it is most certainly NOT to show off) and that should be sufficient. What you should find is that each option has limitations, costs and consequences. One objective of this book is to identify at least some of the limitations and consequences so the reader will acknowledge that there are some things that should not be done, or if they are, it will be at a significant cost.

A further issue for me is what to do about molecular diagrams. By convention in organic chemistry, unless the role of the hydrogen atom is critical to the argument, it is deleted to make the diagrams less messy. I have taken this to a deeper level, and my diagrams are severely truncated by chemistry standards. The reason is, while it may appear nice to have molecular diagrams, if you are not a chemist they are meaningless. What I have done in this book is to recognize that the chemistry I am putting forward is very basic, therefore I shall truncate diagrams so far that only the very essence of the critical parts remains. The idea behind these is that for those unfamiliar with the topic, it may be possible to give sufficient information that some understanding follows. For those who want more detailed or more formally acceptable diagrams, sorry. If you can follow more complex diagrams, you should know the points I am trying to make anyway.

For those with a reasonable knowledge of chemistry, they will know better than any that chemistry is an outlandishly large subject, and in most cases they will have no particular knowledge of this topic. Accordingly, for these readers I have tried to show why certain issues arise. They will also know that an organic reaction that goes from A to B is seldom that simple, a variety of other things can be made, and what is made may be highly dependent on conditions. In what follows, if something can be done, I neglect the complicating additional reactions unless their occurrence would cause significant problems. This is not a discussion on chemistry, and more to the point, I am trying to give a limited understanding of some of the basics. No need to add unnecessary complications. Having said that, I have a chapter where I attempt to illustrate some of the chemical principles that are involved. It may be that this pleases nobody, but I want to at least attempt to show that there are reasons why certain things happen, so that the reader has some chance of realizing what is general and what is not.

I first became involved with biofuels during the 1970s oil crises, when I was at the beginning of my career, and now, at the end of it, once again I am involved. Accordingly, I have some biases, but I hope to show you why I have such biases. However, the reason for the book is not to promote a case, but rather to provide the reader with a broad understanding of the issues involved in any decision-making process.

Chapter 1.

Why?

The purpose of this chapter is to outline why I believe this subject is of prime importance to our society. In my opinion, future society faces three major problems that are relevant to this issue. These are: diminishing oil supplies, global warming and ocean acidification. A fourth issue, Peak Food (Grassini et al. 2013), may be more serious, and it impinges on some of what follows. If the population continues to increase and food productivity does not, and there are reasons why it might not, there may be very limited land available to devote to the feedstocks for biofuels. The eventual answer might be that we have to reduce population, not overnight, but eventually. This issue is simple: if it is necessary to do so, either we do it in an orderly fashion, or the planet will do it for us, chaotically and painfully.

How should we assess a problem like this? The scientist in me says there is only one way: we have to put numbers on the problem. The numbers will not be accurate and do not need to be accurate because at this stage what we are trying to do is to put some perspective on the matter.

Obviously, we have to eat, but we also need fertilizer to maintain our current crop yields, we need fuels to drive our tractors, we need fuels to bring produce to market, people need fuel to get to the market, and they need fuel to go to work to earn the money to be able to buy the food. Most of our current nitrogenous fertilizer comes from oil (or gas) and almost all of our transport fuel comes from oil. Apparently, at any given time, approximately 61,000 people are airborne over the US, and I have heard a report of questionable authenticity that the number worldwide is about 800,000. This requires a huge amount of jet fuel. It also illustrates the first problem: for many of the critical issues, reliable data is difficult to come by. The first job for governments should be to use their resources to define the problem fully. This should be followed by clearly defining what options are possible now, and what could be in the future if certain work was carried out. If we then carried out that work, we would have many of the answers to our problems.

Annual production of oil is currently about 85 million barrels per