Welcome to Charge: the future of energy
HOW DO WE GET FROM HERE TO THERE?
Transitioning to a Sustainable Energy Regime
by Dan Sweeney
Before reading this section, it’s a good idea to read section entitled “Why Renewable Energy?” Unless one can advance compelling reasons for change, discussing the process of change is merely an academic exercise. Obviously, though, we believe that change is necessary, indeed, urgently necessary, and we’re assuming that others are at least willing to entertain that notion.
So here’s the scope of the problem and some possible solutions.
Where We’ve Come from and Where We Are
As the world’s most successful large land animal, we humans have spent most of our career as a species living on renewable energy. First it was sun and biofuel—mostly wood, then it was wind and water power, with few things like whale oil and clarified butter thrown in for good measure. It wasn’t until the Middle Ages that coal was much used as a fuel, and then to a fairly limited extent, while petroleum up until the nineteenth century was used only in warfare as a component of the infamous Greek Fire.
In short, we lived almost entirely on renewables for countless centuries before so we could presumably do it again, right?
The problem with trying to go back to renewables, at least as they were used in the past, is that the energy needs of a modern industrial society are vastly greater than those of a premodern civilization resting on a renewable energy base. The entire Roman Empire probably consumed less energy for industrial uses in a given year than a single American city does today. Farms and craftsmen’s shops were operated with the muscle power of men and draught animals, ships ran on a combination of wind power and muscle power, and a relatively small number of water mills were used to grind grain.
The low energy output of the Roman Empire and all other societies that did not go through an industrial revolution consigned their populations to a way of life that most inhabitants of today’s world would prefer not to endure, though in fact hundreds of millions in underdeveloped countries still derive scant benefit from modern production methods. In all premodern civilizations the huge majority of individuals—over 90% in all instances—engaged in subsistence agriculture. Rural populations were subject to frequent famines and to chronic malnutrition even when harvests were relatively abundant. Such civilizations were characterized in the main by great disparities of wealth, despotic and corrupt governments, and by the dissipation of what wealth was accumulated in military aggression. Poor societies are rarely just societies, and only in scattered instances, such as the Swiss cantons of the medieval period, did liberty and respect for the rights of the individual thrive.
Marxist historians rightly deplore the horrific working conditions typifying the early days of the Industrial Revolution, but they cannot deny the rise in overall living standards that accompanied the switch to fossil fuels and mechanized production and the simultaneous positive changes in European society including the overthrow of Absolutist regimes, the abolition of slavery and torture, and the rise of representative governments. We believe that a strong correlation exists between a high standard of living and a humane society. Exceptions exist, most notably the fascist states of the mid-twentieth century, but such states did not endure, and generally rested ultimately upon the exploitation of colonized peoples—in other words, real prosperity was confined to the few.
Western society in achieving its unrivaled standard of living has, over the course of the last 250 years, consumed ever increasing amounts of energy, mostly derived from fossil fuel—first coal, and later petroleum and natural gas as well—and, most recently, nuclear. Renewable energy sources, while never abandoned, have not begun to keep pace. Only large scale hydroelectric projects have achieved respectable output and they have often done so at considerable cost to the environment.
Indeed, practically the whole of modern material civilization is based upon the consumption of fossil fuel resources, and what does not get burned to provide energy is processed into hundreds of thousands of different petrochemicals to build the industrial products used by businesses and consumers.
So how does one effect an easy substitution of renewables for the dwindling store of fossil fuels that have made us rich for so long?
The logistics of doing so are daunting, and according to some pessimists are nearly impossible, at least at this late date.
The Turning Point or What Has to Happen
With the exception of large scale hydro, renewables count for less than 1% of the energy consumed in electrical generation today, though, surprisingly a rather higher percentage of renewables is used in transportation, at least in the U.S. Use of renewable sources, particularly wind power, is growing rapidly, but one may question whether current growth rates are sufficient to keep pace with declines in fossil fuel reserves, on the one hand, and on sharply increasingly worldwide demand for energy on the other.
Unfortunately the past provides us with little guidance in this matter. During the last change in energy regime from wind, water, and muscle power to fossil fuel the transition was relatively smooth and nondisruptive. There was no shortage of wind and water power, and the wind and water mills kept on turning and sailing ships kept on sailing all through the transition period. Coal at first was used primarily in factories which needed a steady output of motive power that only a steam engine could provide. Only gradually did coal migrate to other applications where its use was noncritical such as shipping, and there in particular the transition was very slow, gradual, and noncatastrophic. Steam ships didn’t outnumber sailing ships until well into the twentieth century, and that only happened when the price of coal fell to the point where the greater speed it afforded shipping lines grew overwhelmingly advantageous economically. Railroads were another story; they lacked any serious competitor, but their substitution for horse drawn carriages and canal boats was not caused by any shortage of horses. The world transitioned away from earlier power sources to steam because steam power greatly facilitated manufacturing and transportation and significantly elevated the general standard of living. There was no element of urgent necessity, however, and we could have gone on indefinitely with renewable sources had we chosen to do so.
The situation today is almost entirely different. Rather than embracing different energy sources in order to raise our standard of living we’re doing so because we ultimately have no other choice. In a word, we are being compelled rather than being enticed to do so. Renewable energy sources are not, in and of themselves, likely to bring us a higher standard of living, indeed the cost disadvantage vis a vis the cheap fossil fuel that still prevails today will result in an initial decline in living standards because the price of energy will rise. Unless much higher energy efficiencies are achieved across a range of applications coincident with the changeover to renewables, we are likely to grow poorer, at least in the midterm. The total supply of energy will be constrained and so choices will have to be made as to its use.
For example, the energy intensive manufacture of huge quantities of throw-away consumer goods may give way at least in part to the use of available supplies of energy in mechanized agriculture. Air conditioning may become an expensive luxury and even heating fuels may be husbanded and sparingly used as in England prior to the late twentieth century. Conceivably more goods may have to be locally manufactured to avoid high shipping costs caused by rising fuel prices. The consequences of a serious energy shortfall, which is more likely than not, will be felt in almost all areas of human endeavor and could profoundly reshape our material culture.
Those are our long term prospects. Our immediate prospects are somewhat different.
Since fossil fuels are still in the main a cheaper energy source than renewables, there is no immediate incentive to move to renewables beyond a desire for cleaner air and a degree of apprehension about the concentration of remaining oil resources in the volatile Middle East. Only when fossil fuel prices get really high and stay there does the incentive arise, though to be sure, there are other short term solutions to the problem. The United States, by virtue of its overwhelming military superiority, could conceivably seize Middle Eastern reserves and allocate much of the petroleum to itself. It might thereby enjoy artificially low prices while the rest of the world went short. Such a ploy would not be without dire consequences, but it would constitute a tempting quick fix.
Sooner or later, however, everyone has to become more dependent on renewables. The problem is in managing the change.
The natural tendency, particularly here in the United States, is to do nothing until faced with overwhelming necessity, but such necessity simply won’t manifest itself clearly until the situation becomes rather desperate, and at that point a timely changeover will be very difficult. If fossil fuels were heavily taxed and renewables heavily subsidized, market forces in support of change would begin to exert themselves earlier and the change could be better managed, but the tax burden on individuals and corporations would increase, and the real wealth of individuals would decrease—in other words there would be considerable economic pain associated even with a phased, well managed transition. For this reason many would prefer to believe that no problem exists and that somehow through diligent exploration and by drilling and mining in protected areas and setting aside environmental concerns, vast new finds of fossil fuel will be made and the world will go on as before.
Simply put, the citizenry at large do not want to go through a lengthy period of austerity in order to ward off dangers that few believe actually exist. While professional geologists are well aware of the decline in fossil fuel reserves, the general public is not and political leaders do little to inform them. No public official wishes to be bearer of gloom. Only now is this collective ignorance beginning to dissipate and it’s not dissipating nearly fast enough.
So we’re faced with a choice, a hard choice.
If we wait until fossil fuel reserves run really low and total energy output declines significantly, then severe economic disruptions are sure to occur. Even slight increases in fossil fuel prices have highly adverse economic effects, and, in the case of protracted severe prices increases, those effects become dislocations. In such instances raising taxes to encourage the growth of renewables through public policy initiatives becomes more difficult still. In hard times people want to retain whatever income they can produce.
Many presented with evidence of coming severe shortages simply say, “we’ll cross that bridge when we get to it. If we have to embark on crash programs to increase renewables, so be it, but why do it now when we don’t have to?”
The problem with that position is that it is short-sighted. In order to build capacity for the future steps have to be taken now. We can’t afford to wait until oil reaches $100 a barrel or a resource war starts in the Middle East if it hasn’t already.
Why now? Remember that earlier figure of less than 1%? Let’s take a look at what’s involved in going from 1% to 100%, our eventual goal.
Scenarios for Change
The first problem facing any nation resolved to convert to renewable resources is determining what mix of renewables is desirable. Renewables can probably only be established quickly with major incentives from the government. So who among the renewable source providers gets the incentives and who doesn’t? Or, to put it another way, on whom do we bet?
Wind would appear to be the obvious best bet. Wind power is the leading renewable energy source today and seems likely to remain so for some time. At present wind energy is only a bit more expensive than that produced by coal and natural gas fired generating plants and, moreover, wind farms themselves can be built fairly quickly.
Wind, however, is a poor source of primary base load power simply because it is intermittent, and there’s no immediately obvious solution for that limitation. Wind turbines also require expensive and wasteful converters because, although they do produce AC at fairly high voltages, it is at the wrong frequency.
Another really significant problem is that the best wind resources tend to be located in remote areas and so a preponderance of wind would require a huge amount of new transmission capacity. Wind powered generators are in no sense a drop in replacement technology for fossil fuel fired plants. They require a different infrastructure.
There are also questions as the extent of usable wind resources. While low speed designs exist, they also tend to be low in output, and commercial operations today are almost always placed in high wind regions. Such regions have been thoroughly mapped by the Department of Energy and the Department of the Interior and they are not only limited in geographic scope, they are very unevenly distributed. Many states have very limited wind resources including some of the most populous, and this necessitates filling less populous areas with wind farms that produce no direct energy benefits to those areas. It also makes the nation as a whole highly vulnerable to catastrophic power outages since primary resources are concentrated in a few areas. Furthermore, much power is lost to electrical resistance when electrical power must be transmitted hundreds of miles.
Yet another problem with wind power is the very low output of wind farms per acres of ground taken up by them. Simply put, wind farms vie for land that could be put to other uses, though fortunately, they can coexist with many agricultural enterprises. In general, large wind turbines cannot be placed in residential areas due to the fact that they generate objectionable amounts of infrasonic sound.
Finally, wind power provides no immediate solution to the problem of what energy source will be used to power vehicles. Public transportation could conceivably run off wind produced electricity but probably not automobiles, boats, airplanes, farm vehicles, and construction equipment. Some have suggested that the transportation industry could transition over to hydrogen which could be generated with wind produced electricity, and that is a possibility. But a rapid transition would be difficult for reasons explored in a later section.
What of the other renewable resources? Apart from hydroelectric power, which is fairly fully exploited already, and is even more geographically restricted than wind, there are only two sources with the potential to be developed fairly quickly, solar energy and biofuel. Both present problems of their own.
Solar generation based upon photovoltaic devices is fine for backup power or off-grid residences but is many times more expensive than wind in large scale power generation, and it’s even more problematic in terms of infrastructure because the solar cells output low voltage direct current that is difficult and expensive to convert to high voltage alternating current. For this reason few see solar panels figuring significantly in large scale generation within the foreseeable future.
Now it is also possible to concentrate solar energy by means of reflectors and use it to heat a working fluid to drive a generator turbine or heat engine or to heat a plasma that can produce electricity directly, but solar generators based on such technologies remain too expensive to be anything more than experimental, though prices may decline signficantly. The fact that various designs have been tried over a period of a century and have remained commercially infeasible suggests that fairly intractable fundamental problems may ie at the core of the technology. Solar resources are arguably more abundant than wind resources, but for solar to assume primacy the technology must evolve in ways that are not immediately foreseeable.
There is a third way in regard to solar energy, the use of thermoelectric devices for energy conversion. Such devices convert heat rather than light into electricity directly and involve thermally conductive collectors. Traditional thermoelectric devices based upon the Seebek principle are inefficient and will always be confined to niche applications, but a number of solid state devices utilizing various quantum effects have been recently developed and appear to have promise. Some of these new devices are said to achieve conversion efficiencies of over 50%, far higher than those for any commercial photovoltaic cell. Whether such technologies can be realized in affordable commercial products remains to be determined, however.
Bio-based Energy Sources
Biofuel is already a very big industry and is poised to grow much bigger. Petroleum and natural gas substitutes are even now being produced in quantities from biological resources and these could be used both to power vehicles and to run conventional generator plants now using petroleum and natural gas. Of all the major renewables biofuel is the closest to being a drop in replacement, and one that would be minimally disruptive to implement. Some redesign of vehicular engines or generator turbines might be required in some instances, but entire industries would not be compelled to change direction overnight.
So why not biofuel?
We believe that at least some forms of biofuel may gain widespread acceptance in the future, but simply replacing fossil fuels with biofuels isn’t that easy.
One thing to keep in mind is that two of the three dominant fossil fuels, petroleum and natural gas, are very easy and inexpensive to extract from the ground. Both involve drilling holes and then standing back and watching the chemical riches surge up. (Coal is another matter, requiring dangerous, dirty, and expensive mining operations.) Biofuels, on the other hand, are produced from feedstocks which are raised as commercial crops. These in turn take up a lot of valuable land and consume much energy in their production if they are grown with modern agricultural methods. The refinement process consumes further energy and much controversy surrounds the issue of whether any or all biofuels can be produced with a net energy gain. If they cannot, and if instead, more electrical energy is required in their production than they yield back when used in engines and generators, then they merely constitute a source of energy storage and one that might arguably be inferior to hydrogen.
Most recent studies suggest that at least certain biofuels can be produced in such a manner as to register some energy gain, but biofuel is still unimpressive compared to fossil fuel, particularly petroleum. Gasoline, kerosene, and diesel deliver an enormous amount of energy compared to what is required to extract, refine, and ship them, and biofuel is unlikely to ever equal them in this regard, though this is disputed by some biofuel manufacturers. If in fact biofuel is inherently significantly more costly to produce than refined fossil fuels, then energy would be relatively scarce and expensive in a biofuel dominated economy.
So that leaves what?
The other renewables are, in order of their current importance, geothermal, micro-hydro, ocean energy, and nuclear fusion. None of these accounts for any appreciable portion of global electricity generated today, and their future importance remains to be determined.
Geothermal energy is, as the name implies, thermal energy emanating from the earth itself, and it takes two principal forms, active geothermal and passive geothermal. In active geothermal generation steam welling up from great depths is used either to power a turbine directly or to heat a working fluid. Natural geysers where such steam is available are, as one might imagine, quite scarce, and most of the more promising sites have already been exploited. It is also possible to inject water into subterranean reservoirs where the temperature of the rocks is sufficiently elevated to generate steam, and this is known as dry hot rocks technology. So far it has not proven economically justifiable because of the necessity of drilling in excess of 10,000 feet to reach such “heat mines”, but as fossil fuel grows scarcer the expense may be warranted. Geologists are sharply divided as to the potential for dry hot rock generation. Some feel that in appropriate settings, such as the Western United States and Australia, enormous amounts of energy might be extracted in this manner, perhaps enough to eliminate dependence on fossil fuel generation altogether. Others believe that the technology is extremely immature and may never contribute significantly to the overall energy budget.
Experiments have also been undertaken in volcanic craters where pipes have been sunk into lava pits and water circulated through them to produce steam, but such ventures have not been notably successful, and, even should they eventually succeed, could never address any sizable portion of a nation’s energy needs.
Recently a small entrepreneurial company calling itself PowerTubes has developed a micro-geothermal generator which it claims can be used in residential applications and remote power in many geographic areas. If these claims are true, this may be a breakthrough product, but we have seen no independent evidence supporting such claims.
Passive geothermal refers to the use of heated air or water for climate control. It’s fine as far as it goes, but it can’t by its very nature figure in electrical generation though it can reduce the dependence of individuals on the grid.
Micro-hydro or small scale hydroelectric generation is a technology best suited to off-grid homesteads and rural communities with no access to electric utilities. Almost any source of flowing water might lend itself to micro-hydro generators, but the amounts of energy generated in any individual instance are usually quite modest. No one is suggesting that a modern industrial civilization could run on micro-hydro.
Ocean energy generally refers to tapping the power of ocean waves or tides to generate electricity. The notion has occupied the minds of inventors for decades and numerous designs have been conceived and a few even built. To date only a handful of actual plants have been constructed and those have been largely experimental.
The problems in either approach are rather different and so are the technologies employed.
Tides consist of continuous if intermittent flows and in this respect resemble the river currents used in terrestrial hydroelectric plants. Thus they lend themselves to water turbines which themselves represent a mature technology. The problem one faces is that regions of strong tides are uncommon and geographically scattered. Then too, tidal generation facilities have been very expensive to construct. Recently, new schemes for tidal generation have been conceived, and new companies launched to commercialize them, but as it stands, tidal energy has a very long way to go before it has proven itself in the marketplace.
Waves are everywhere and are frequently highly energetic. Unquestionably the hydraulic energy impinging upon our shores from moment to moment is prodigious, and if only a tiny fraction were to be tapped, our energy problems would be greatly eased. Still the fact that a half century of experimentation has resulted in no generally accepted designs is indicative of the magnitude of the technical challenges facing those who would harness the energy of the waves.
Wave generators to date have tended to be mechanically complex and their designers have had difficulty constructing machines that could operate effectively over a wide range of wave heights and survive violent surf conditions. Anchoring the machines and running electrical cable back to shore pose another set of problems. It is difficult to overstate the destructive force of large ocean waves, and all shores that are not sheltered are visited by such waves with some frequency. Not surprisingly, no one to date has conclusively demonstrated that wave generation plant could achieve long term reliability.
Other types of ocean energy generators have been proposed that would exploit temperature differentials in the water to produce mechanical motion and drive a generator or that would exploit regions of strong ocean currents like the midAtlantic. At present such schemes are purely theoretical.
Fusion energy has in the past aroused great interest among those concerned about the eventual unavailability of fossil fuel sources. Fusionable materials are superabundant and the energy produced by even the smallest quantities of them is so great that humanity could comfortably anticipate tens of thousands of years of high intensity electrical generation before such sources became noticeably scarce. So why not fusion?
Experimental fusion reactors aplenty have been built, the first designs going back to the sixties, indeed before the first commercial fission reactors came on line. Such experimental reactors have indeed produced energy, but, with one highly questionable exception, have not been reported to have produced more energy than was required to initiate the fusion reaction. And unless a net energy gain can be registered the technology is useless.
What are the prospects of anyone ultimately succeeding? One would really like a definitive answer to this question, but no one has been able to offer one. Most scientists who have studied fusion believe that a successful reactor is theoretically possible. Its existence wouldn’t appear to violate any laws of physics, and the fact that slow but steady progress has been made over the decades, i.e. the gap between energy in and energy out has been dwindling, suggests that the corner might eventually be turned.
Unfortunately there’s no easy answer there either. Numerous designs have been attempted over the years and considerable debate exists among fusion advocates as to which is the most promising. All of the major design variants have progressed and improved but none has achieved real success.
During the initial phase of fusion research in the sixties and seventies most scientists in the field predicted practical reactors would have appeared by the turn of the century. Obviously they were wrong. Today most responsible researchers state that commercial reactors are decades away.
The problem in such predictions is that multiple technical breakthroughs in multitudes of different scientific fields will be required for any design variant to succeed. A whole range of problems in applied physics and electrical engineering will have to be solved and solved completely before the technology is ready. Predicting precisely when and if such breakthroughs will take place is obviously extremely difficult.
Some have suggested that if more funding were given to fusion research an accelerated development cycle might occur, but fusion research has already been funded in amounts of tens of billions of dollar—more than for any other form of sustainable energy. The reward for such investment has been absolutely nil to date.
Fission Nuclear Reactors
Fissionable materials do not constitute a renewable resource but they are currently a very abundant source of energy, possibly sufficient to sustain high levels of electrical generation for a longer period than would coal. Obviously there are significant dangers associated with the transport and disposal of such materials and with their misuse in covert weapons programs. Moreover, nuclear reactors are expensive to construct and are not currently cost competitive with fossil fuels as energy sources absent government subsidization. A handful of countries, most notably France and Japan, derive a large percentage of their electrical power from nuclear generators. In many other nations such as our own nuclear development programs are currently moribund and aging plants supply what energy is produced.
In the event of severe and protracted shortfall of natural gas and petroleum, the temptation to resume building fission reactors might become irresistible. They could be used both for base line power generation, a task for which they are well suited, and for powering plants producing substitute fuels for transportation such as hydrogen, syngas, Fischer-Tropsch process fluid fuel from coal, and so on. That such an eventuality will occur in the United States is by no means unlikely because nuclear energy is an established technology, the fuel itself is neither scarce nor threatened, the power plants themselves fit well within the legacy transmission grid, and the nuclear industry has a well entrenched and powerful political lobby.
Whether or not such a state of affairs comes to pass, no one should think that a rapid buildup a nuclear power plants is going to enable developed nations to continue to use energy as they have in the recent past. Nuclear energy will be expensive, probably more expensive than wind, and it may well establish itself as an unregulated monopoly service which would tend to drive prices still higher. Furthermore, transportation fuel produced by means of such energy will be expensive as well. In short, an energy regime anchored by nuclear reactors is apt to result in a declining standard of living in industrial countries.
If energy shortages grow acute as the century advances, a distinct possibility, then some of the chancier schemes for energy generation will be likely to gain a hearing. Here are a few of them that might be attempted if the world’s energy needs cannot be met with the more conventional renewables.
High Altitude Wind
Wind velocity increases with altitude. The increase is measurable at only a few meters above the ground and when one reaches elevations above ten thousand feet then gale force wind speeds come to be encountered fairly frequently. Since the output of wind turbine increases with the square of the wind velocity, faster is definitely much better.
Serious proposals have been made to launch turbines that would be moored at substratospheric elevations. Some such schemes would use balloons to keep the turbine aloft while another concept, one advanced by Sky WindPower, Inc. of San Diego, is to use a turbine that is a combination helicopter and generator and uses some of the wind force to keep aloft and some to generate electrical power. The turbine uses an electric motor to launch the turbine to the requisite height and then relies on prevailing winds to keep it aloft. A conductive mooring cable conveys the electrical energy to a base station on the ground. The company has constructed a working scale model but has been unable to find the funding to build a full sized generator. The principals of this company are serious researchers with strong academic backgrounds in aerodynamics, but the audacity of the scheme is sure to give investors pause, and, given the fact that terrestrial wind farms can be relatively cheaply constructed, and because terrestrial wind capacity is far from exhausted, we would not expect such proposals to be seriously entertained unless a major crisis were to develop.
Another startup named Aeolus, Inc. has proposed immense multi-rotor vertical axis offshore turbines of which a handful would produce the output of an entire wind farm. Again the scheme appears to have technical merit, but attracting sufficient investment to proceed is likely to prove difficult.
Some serious proposals have even been made to launch enormous solar generators into orbit around the earth and return energy to earth via microwave. Leaving aside the dangers posed by such a high intensity transmission, the logistics of setting up such orbital generators would be exceedingly difficult. But if more conventional technologies prove insufficient to meet demand, who knows?
Still other entrepreneurs advocate returning maritime transport at least partially to wind power. Conventional gas turbines and diesel engines would be supplemented with radical high lift wing sails thereby considerably reducing fuel consumption. Small craft based upon such principles have in fact been constructed, most famously the late Jacques Cousteau’s Calypso II.
We could go on ad infinitum here, eventually reaching the domain of “over unity” schemes, the current version of perpetual motion, and determining exactly where radical innovation shades into crank theories and projects can be somewhat difficult. What can be said with some certainty is that technologies that are still in the theoretical stage today are unlikely to be realizable in commercial form in time to forestall a crisis in energy generation if the more established renewables prove incapable of filling the gap.
So where does that leave us in respect to strategic planning for meeting our energy needs in the future?
Several interrelated courses of action suggest themselves.
Construction of wind farms should proceed apace but with the clear understanding that wind power by itself is at best a partial solution to our energy needs and may never meet more than a fraction of the total demand for energy.
Rigorous assessments must be made of the prospects of immature technologies such as ocean energy, nonphotovoltaic solar generators, thermoelectric generators, and fusion, and financial incentives developed to foster the most promising. This amounts to an industrial policy and some would object on those grounds, but the consequences of a severe energy shortfall are too serious for those objections to prevail.
In so far as possible distributed energy generation schemes should be encouraged down to the residential level. These lead to increased energy security and encourage experimentation and validation of emerging alternative energy technologies. In such a setting a new technology has a chance to prove itself while limiting risk to the overall society.
Equal emphasis should be given to improving energy efficiency in all industrial, residential, transportation, and personal uses. New technologies as applied to heat engines could more than double the efficiency of vehicles and could postpone a fossil fuel crisis for decades. Energy efficiency in regard to buildings could reduce energy expenditures by a further several percent. Improved efficiency in electrical transmission could also make a major difference.
Technologies for extracting clean burning natural gas substitutes from petrochemical wastes such as old tires and discarded plastics should be explored. Approximately fifteen percent of petroleum is utilized in the production of petrochemicals and not all of the resulting products are recycled.
Clean coal technologies, and by that we mean close to zero emission rather than reduced emission, should be seriously considered. Coal is by far the most abundant fossil fuel resource, and near zero emission coal generators, which are possible today with certain new technologies, could anchor a transitional energy regime. Clean coal technologies are close to a drop in replacement for existing generation facilities though there will be considerable expense in implementing them.
Finally, petroleum must be phased out of transportation and quickly. Most of the remaining oil reserves are concentrated in the Middle East and that supply is held hostage to political events and subject to extreme price fluctuations. The economic consequences of continuing to rely upon that supply to meet basic transportation needs are so serious as to demand immediate action to lessen that reliance.
In many ways managing a move away from petroleum in transportation constitutes the greatest challenge in establishing a total independence from fossil fuels and we have devoted an entire section to discussing the matter.
The transportation industry today is almost totally dependent upon the burning of fossil fuel to generate propulsive force. That dependence consumes most of the petroleum produced today. Since rapid transportation of goods and individuals is absolutely necessary for the maintenance of our modern economy, this almost total dependence upon a single energy source represents an enormous vulnerability. Any protracted interruption or significant lessening of oil flow could bring Western economies to a standstill.
So what can be done to lessen and eventually eliminate this vulnerability?
Unfortunately, the answers here are as elusive as in the case of electrical generation. There is no entirely obvious technological fix that may be immediately implemented. But there are promising paths to be pursued, some more promising than others.
As in other energy uses, transportation today is rife with inefficiencies. Most gasoline automobile engines are less than 20% efficient in converting the energy of combustion into mechanical energy, while the diesel engines used in trucks, locomotives, and watercraft are at most about 40% efficient in that respect. Aircraft engines in general are highly inefficient.
Furthermore, most automobiles and trucks are aerodynamically suboptimal and far heavier than they need be to protect their occupants. Major improvements in either area could cut fuel consumption even absent improvements in internal combustion engines. Combined with such improvements, mileage might be tripled or even quadrupled.
Still it must be said that the process of improving the efficiency of automotive and marine power plants is replete with uncertainties if for no other reason than that the best and most cost effective means for doing so are a matter of dispute.
In most of the coverage appearing in the popular press on the subject, the underlying assumption appears to be that the internal combustion engine will be phased out in favor of hydrogen powered fuel cells, with hybrid vehicles functioning as the transitional technology. Actually such a scenario represents but one possibility.
Fuel cells at present sell for a minimum of $5,000 per kilowatt, small quantity pricing. At that rate a 100 horsepower automobile power plant would cost in the six figures. Fuel cell manufacturers assure us that volume production could bring down such prices, but how much? We believe that prices have to drop by two orders of magnitude for the technology to be viable, and that such reductions could soon be realized in devices that have previously required precision machining, complex assembly procedures, and expensive materials is by no means assured.
Moreover the fuel cell is but one part of the cost equation. A fuel cell power plant requires an electric motor or motors, preferably high efficiency, light weight, high output motors of the sort that command five figure small quantity prices today. These must be supplemented with complex power management systems and probably with auxiliary electrical power source such as costly exotic batteries and even more costly ultracapacitors. And let’s not forget the fuel storage system, which if hydrogen is used, will be either a cryogenic tank or a high pressure tank made of advanced composites. Both are quite costly today and provide limited range. Again economies of scale would be certain to obtain and costs of manufacturing could decline, even precipitately, but no one has convincingly demonstrated that fuel cell powered vehicles could achieve price equivalence with those utilizing conventional power plants within the near term or even the mid term. The fact is that fuel cells are, to a considerable degree, still experimental devices, and the fact that progress in perfecting them has been so slow is hardly encouraging.
So what are the other options?
Hybrid vehicles are already in the marketplace and do outperform conventional vehicles in terms of efficiency by a wide margin. The rationale behind hybrids is fairly simple. Engine fuel economy directly correlates with displacement, and large displacement engines represent wasted capacity most of the time since their maximum horsepower is generally only invoked during hard acceleration. With hybrids the energy stored in the batteries can be dumped into the system when momentary bursts of energy are required and therefore a relatively small internal combustion engine with little reserve capacity can be used. Furthermore, if the internal combustion engine drives a generator rather than a conventional transmission, the engine can always be operated at optimal efficiency. Finally, considerable energy can be recovered through regenerative breaking where an electrical generator is used to exert a braking action on the wheels and the resulting electrical energy is stored in a battery or ultracapacitor.
The problem with hybrids is cost, and hidden cost at that because to date their production has been essentially subsidized. The power plant of the most successful hybrid, the Toyota Prius, is very expensive to manufacture, utilizing costly motors and batteries as well as an innovative limited production internal combustion engine and a complex energy management system; the company is said to lose money on every sale. If this is to become the prevailing technology for transport in the near term we may expect absolute prices for automobiles to rise. The manufacturer is in effect installing two parallel power plants, an internal combustion engine and a battery powered electric motor, and two power plants are always going to cost more than one.
Some have suggested that the best course for the midterm and perhaps for the longer term is to abandon the hybrid notion altogether and concentrate on producing really high efficiency heat engines. A number of technologies, some proven, some still experimental, exist for increasing efficiency by a factor of two or even three, including new designs of rotary engine, pulse detonation, ram jet aspiration, the Miller cycle, direct injection, and so forth. We believe that enough progress has been demonstrated in high efficiency engine design that it is now reasonable to assume that required gains in efficiency could be attained through these means alone and without resorting to hybrid power plants. Furthermore, such innovative engines are likely to prove much less expensive to manufacture than either fuel cell power plants or hybrids, and perhaps ultimately less expensive than conventional reciprocating engines.
So why not take this route?
Unfortunately, the previous experience of the transportation industry in developing new types of power plants has been rather discouraging from an investment perspective. The one truly innovative design to establish itself in the marketplace, the Wankel engine, took almost forty years and tens of millions of dollars to commercialize. A recent refinement of the Wankel, the Rotapower, consumed $60 million dollars of investment and isn’t on the market yet. To cite yet another example, Mazda’s new high efficiency direct injection gasoline engine involved years of research and $110 million dollars of funding to bring to market.
Most innovative designs build on concepts originally developed in the late nineteenth century. They’re actually failed designs that have been tried before, but which exponents believe can be made to work today with advances in fluid dynamics, materials technology, and computer modeling. And in some cases they can, but even if they can, productization is apt to be a long, difficult process.
We see little evidence that automobile manufacturers are currently giving serious consideration to radical new designs of heat engines, however, and a number of reasons for their intransigence in this regard suggest themselves.
Auto manufacturers have traditionally avoided radical innovation. Bureaucracies that they are, they don’t foster creativity or attract inventors, and at the same time the auto companies dislike paying licensing fees.
Auto manufacturers have tremendous amounts of investments in legacy tooling. Radical new designs would render that capital investment worthless. Finally, the auto manufacturers are assuming that the cars of the next decade will be filled with electrical subsystems, including large onboard computers, electronic transmissions, drive-by-wire steering and brakes, onboard radar and navigation, elaborate information and entertainment systems, and telematic systems complete with multiple wireless transmitters. These will demand deep reserves of electrical power, reserves that can best be provided by hybrids and/or fuel cells.
All this would suggest that hybrids of one sort of another will lie at the heart of any strategy for improving fuel economy. True, fuel cells are garnering most of the publicity but very possibly the professed allegiance of auto makers to this concept is due to government incentives to produce such vehicles. We see absolutely no evidence that a fuel cell powered vehicle could be profitably produced within this decade.
Before we leave the subject of transportation, something should be said concerning other types of vehicles such as heavy trucks, railways, aircraft, and water craft, since in aggregate these actually consume more fossil fuel than personal transportation.
Heavy trucks almost universally use energy efficient but highly polluting diesel cycle compression ignition engines. Because enormous improvements in fuel consumption cannot be had from the newer technologies of fuel cells, hybrid, and innovative heat engine designs, trucks are likely to continue to use such engines far into this century, though they will probably transition to so-called enhanced diesel engines that produce less pollution than the traditional kind. Lower polluting fuels such as bio-diesel may be substituted for heavy petroleum but how quickly or extensively cannot be determined. Fuel cells and hybrids are certainly possible in such vehicles and could be extensively adopted there if government incentives were in place, but whether governments will act in this manner is uncertain.
Ship and boats generally use high efficiency diesel engines. Further considerable gains in fuel economy could be had by a move toward surface effect or air cushion hulls rather than conventional displacement hulls. At least a doubling of fuel efficiency is likely to be realized by this means, though the cost of construction would rise. Fuel cells have also been proposed as shipboard power sources, but existing models aren’t nearly large enough and are far too expensive.
Work is underway toward the development of hydrogen powered jet aircraft but commercial products are probably decades away (the very first German jets were hydrogen powered). Some of the manufacturers of innovative heat engines such as Quasiturbine and RandCam are also eyeing the aircraft market. Fuel cells have even been used in airplanes on an experimental basis. Finally, considerable effort is being devoted to the development of a nuclear power plant for jet airplanes called a triggered isomer reactor, though concerns about nuclear waste hazards could prevent such efforts from bearing fruit. We see a transition to fuel efficient power plants occurring very slowly in this field.
In sum we see vehicle efficiency definitely increasing, but regardless of how much more overall fuel efficiency is achieved, inevitably petroleum resources will be stressed over time if for no other reason than that demand in developing countries is increasing rapidly—so much so that even maximal increases in efficiency achieved within a few years from now may not compensate for declines in production on the one hand and increases in demand on the other.
Today the technology and economics of renewables are not such that a smooth transition toward renewable energy sources can be anticipated. That such a transition will have to occur is almost indisputable, however.
The best case scenario would be one in which governmental policies in both the developed and developing world encourage innovation in alternative energy technology and ease the gradual replacement with finite fossil fuel sources with renewable energy sources. The specifics of this process are far beyond the scope of this cursory consideration of the problem, but one can cite previous examples of where governmental initiatives encouraged the rapid development of new technology and its transfer to the private sector. Jet aircraft and semiconductors are merely two examples.
The worst case scenario is one where fossil fuel prices climb remorselessly as supplies are exhausted, and where a transition to renewables is delayed until the very survival of industrial civilization is threatened. In such a case funding the necessary research becomes much more difficult, particularly if the competition for the remaining fossil fuel reserves results in frequent armed conflicts, or, worse still, in the deliberate sabotage of fields and refineries by those determined not to reward aggressors seeking their wealth.
One can also imagine an infinitude of better and worse case scenarios between the two extremes but these we need not explore. Suffice it to say that a change under best of circumstances will not be easy and under worst of circumstances will be agonizing. But that change can be avoided is simply not possible.