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Paul Mobbs – Energy Beyond Oil

Turning the World Upside Down

Published in an edited form in The World Today, the journal of the Royal Institute for International Affairs (Chatham House), vol.60 no.12, December 2004.
© November 2004 Paul Mobbs, released under The Creative Commons Attribution Non-Commercial Share Alike License.
For further information contact: http://www.fraw.org.uk/mei/ or mei@fraw.org.uk.
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Could you live with the same amount of energy now available to those in the third world? A dramatic change such as this is likely within fifty years as present energy sources are used up. So future generations will have to manage with just a third of the energy we use now.


Oil is a finite resource. More significantly, studies dating back to the mid-fifties show that oil production begins to drop off significantly as an oil field reaches about half its productive capacity. The 1970 peak in US oil production, and its subsequent decline, were predicted in 1956. Likewise the peak in the North Sea production, predicted some years ago, occurred in 2000/2001.

What has become controversial is the application of these same techniques to global oil production. Various studies put the date of the global peak in oil production between 1996 and 2035. However, most put the date between 2008 and 2016. Recent oil price rises are, in part, a result of a decline in production relative to demand. This is the trend we would expect to see immediately before a peak in global oil production. However, whether or not we are experiencing “peak oil” will not be determined for some time. It will take a number of years of production statistics to demonstrate this.

Oil represents around 35% of global energy supply, and natural gas another 22%. Therefore, within one or two decades, one-third of the world's present energy supply will be in decline. Within three or four decades, after the peak in gas production, it will be one-half. Clearly, even if we did not face the hazards of climate change as a result of fossil fuel use, we have to find alternative energy sources to replace oil and gas within the next one or two decades.

The problem with replacing petroleum or gas is that they are very dense sources of energy. Fossil fuels represent tens of thousands of years of solar energy captured within plants and animals. Consequently fossil fuels create a lot of energy per unit of volume, and are able to create large heating or power loads cheaply with minimal engineering.

Nuclear

When we think of alternatives, nuclear power is often promoted as the most reliable option. This is not so. Whilst those opposed to nuclear power believe that it will never be successful because of its high cost, the principle limitation to the use of nuclear power is the availability of uranium. The 'thermal' nuclear reactors used around the globe use one isotope of uranium that comprises just 0.7% of all uranium resources. Nuclear energy provides around 6.6% of the world's energy supply, and at this rate there is enough uranium to keep thermal reactors running for 100 years. However, if you significantly increase the amount of energy produced by thermal reactors the lifetime of the resource shrinks accordingly. For example, if nuclear were to provide in excess of 30% of global energy supply then uranium resources might only last two decades.

The only way to significantly extend the life of uranium reserves is to develop fast-breeder reactors. These are able to convert the unused uranium into plutonium, which can then produce energy by the same process as thermal reactors. The problem is that the design challenges of developing a fast breeder reactor mean that no safe and commercially-viable system has yet been developed.

Another option is nuclear fusion. This uses hydrogen isotopes extracted from water to produce energy, and creates only a fraction of the radioactive waste of conventional nuclear reactors. However, it may take four or five decades, perhaps more, to develop a viable fusion system. Clearly, that's not fast enough to counteract the imminent shortfall in energy supply.

Low Carbon

"Low carbon" energy technologies use waste or plant matter to produce energy with a lower level of greenhouse gas emissions than fossil fuel sources. The problem is that most low carbon technologies seek to operate in a way that does not require change within society. For this reason the mismatch between the high level of energy use within industrialised society, and the low level of energy available from low carbon sources, makes them un-viable in the longer term or at large scales of production.

Energy crops are the principle low carbon technology. Crops can be grown and burnt to produce heat and power, or processed to produce liquid fuels or gases. The main drawback is that it takes a large amount of land to produce them. For example, one hectare of oilseeds will produce enough biodiesel to keep a car running for one year. However, if we factor-in the level of petroleum consumption by all the vehicles and trains in an industrialised country the area of crops required may exceed that country's entire land area.

One solution to the land-demand issue is for states with a large land area to grow and process energy crops for export. However, as a large part of the nitrate fertiliser used to grow these crops is sourced from natural gas, and as climate change reduces the availability of agricultural land, this is not a practical option in the longer-term as it might endanger food production.

The Hydrogen Economy

Some states are investing in the development of hydrogen energy, in particular hydrogen powered cars. The problem is that hydrogen is not an energy source. It is a carrier of energy in the same manner as we utilise electricity. To get energy from hydrogen you must first put a larger amount of energy into its production. Currently most of the world's hydrogen originates from the petrochemical industry, where it is produced as a by-product of refining. Hydrogen can also be produced by other processes but this requires an even larger energy input. Thus the un-answered question in relation to the hydrogen economy is, "where does the energy come from?"

In reality hydrogen is not a dense source of energy. Natural gas contains more energy than a similar volume of hydrogen, and the transportation of hydrogen is problematic because of its explosive nature. One solution to transporting hydrogen is the production of fuels that can be processed to produce hydrogen at the point of use, such as methane or methanol. However, the effect of these precursor fuels is to further increase energy demand as they lower the efficiency of the system.

Renewable Energy

Renewable energy can be extracted from the Earth's natural systems. The principle form of renewable power across the globe is hydro-electricity – creating about 2.3% of the world's energy sources. However, the hydro-power sector is dominated by large-scale projects that can be damaging to the environment, and this limits the opportunity for development.

Wind power is developing rapidly because large capacity turbines can be developed with little effort. The principle problem with wind power is its unpredictability. For 60% to 70% of the time the output from wind turbines must be backed up from other sources. Currently most wind farms are backed-up by fossil fuel systems when their output falls.

There are other significant sources of renewable energy, such as tidal energy, wave power, and of course solar energy systems that provide hot water or electricity. However, these technologies are not receiving the same attention as wind power because they do not easily scale-up to a level that is able to compete with large fossil fuel or nuclear power plants.

A World Turned Upside Down

Given the current trends in fossil fuel use, and the physical restrictions of the alternatives to fossil fuels, before the middle of this century global energy consumption must begin to fall. If we look one hundred years ahead it doesn't matter if we reduce fossil fuels and switch to renewables, or we burn all the oil, gas, coal and uranium in the world in order to keep energy consumption growing at its current rate. Global energy use will have to shrink by 60% to 70%. Whilst this may sound dramatic, in real terms it means that the populations of the industrialised nations will have the same per capita energy consumption as those who live in developing states today.

The critical issue we must resolve in the near future is how we will manage with less energy. For most governments this is not palatable because it requires a level of change as fundamental as the Industrial Revolution. Currently a large part of the globe's energy supply powers the movement of goods and people. After this the most significant use of energy is the production of electrical power. Consequently it is these two areas of the energy economy that will undergo the greatest change. However, this change need not be problematic. What we need to do over the next two or three decades is significantly reform our systems of energy use to make them smaller in scale and more efficient.

For example, if we were to dismantle national power grids, replacing them with small plants serving large neighbourhoods, generation could switch to combined heat and power (CHP) to provide heat and electricity. In a country such as the UK, this single change might save up to 15% or 20% of the national energy supply, mainly through the increased efficiency of CHP systems. The other benefit of smaller energy grids and CHP is that it complements the small scale nature of most renewable technologies. More importantly, it allows small scale solar on individual buildings to provide a large part of the energy demand during the hot months. Then the local energy production system can be sized to produce the bulk of energy demand during the colder months when wind, hydro-power and energy crops are more readily available.

In many ways, a world using 60% less energy is 'a world turned upside down'. Instead of global systems of economic production more localised systems predominate. The production of foodstuffs and food commodities would have to be localised, as this uses less energy for transportation. Commodities overall may be in short supply, but they would have to last longer and work more efficiently so that overall the commodity was more energy and resource efficient.

The key feature of this 'upside down' future is that the small-scale technologies it relies upon are already available, in contrast to other 'technological' futures which rely on systems yet to be perfected (such as nuclear fusion or nanotechnology). Given that the time scale for such a change is thirty to sixty years, what society must decide is when this transformation should begin: Before the real energy shortages begin, providing greater certainty but short term disruption. Or after the shortages arrive, risking a longer period of disruption created by resource and energy shortages.





Paul Mobbs/Mobbs' Environmental Investigations – http://www.fraw.org.uk/mei/
© 2004 Paul Mobbs. This document has been released under The Creative Commons Attribution Non-Commercial Share Alike License (by-nc-sa, version 3).