| Livestock Research for Rural Development 22 (4) 2010 | Notes to Authors | LRRD Newsletter | Citation of this paper |
Key words: Energy, EROI, greenhouse gases, heating, hydrocarbons, nuclear, oil, population, solar energy, temperature
| Mikhail I. Budyko1969 of the Main Geophysical Observatory, Leningrad, Soviet Union, wrote in 1969 that “all the energy used by man is transformed into heat, the main portion of this energy being an additional source of heat as compared to the present radiation gain”. He pointed out that this heating was over and above any climate forcing from anthropogenic greenhouse gases and—since energy use was growing geometrically—it was likely to result in the retreat of the cryosphere, accompanied by excessive and potentially damaging global warming, perhaps in 200 years or less. |
The reality of global warming has come under constant scrutiny by the lay public and news reporters in the last few months - largely because of some unfortunate and illegal access to private emails sent between scientists foremost in this field and some errors of fact published by the IPCC in their latest reports. The most quoted reference is to the statement that all Himalayan glaciers may have melted by 2030 based on a guess by one Indian scientist who probably was over anxious about that possibility because of its implications for the livelihoods of the 600 million people that would be affected on the Gangetic plain. Yet undoubtedly the glacier are melting and the rivers they feed are so over utilized for irrigation and other uses that many now fail to reach their destination (sea or lake) during part of the year. Nevertheless, the degree and extent of the criticism has done much to make people more complacent about the dangers of global warming and resource depletion.
In general, global warming is attributed to anthropogenic releases of carbon dioxide, methane and oxides of nitrogen and their accumulation in the atmosphere. This results in increased absorption in the planet’s atmosphere of infra red radiations emitted from the earth’s surface which in turn had been received from solar radiation.
The accumulation of greenhouse gases in the atmosphere has been gradually increasing; driven by the burning of fossil fuels to meet the energy needs of an increasing population and greater wealth. Since the beginning of the industrial revolution, energy demand has continuously increased (almost exponentially) and this has been largely supplied by the combustion of the hydrocarbons, coal, natural gas and oil, that had been sequestered in various parts of the world’s crust over millions of years. These reserves are finite and non-renewable.
The greenhouse effect (gaseous atmospheric pollution) has been implicitly blamed for the increase in average global land and sea temperature as it is well established these gases are warmed by infra red radiation. However, the effect of burning hydrocarbons on heat accumulation has been considered insignificant and yet the first law of thermodynamics – that energy can neither be created nor destroyed - means that the energy in all the hydrocarbons burned must be conserved on the planet as heat. Another source of heat is that released when nuclear reactions occur when bombs are exploded or nuclear power stations transmute uranium and generate steam to drive the turbines and produce electricity. World-wide the burning of hydrocarbons and the application of nuclear reactors generate sufficient heat to account for 74% of global warming according to papers published recently by Swedish scientists (see Nordell and Gervet 2009). If proven to be true, the amount of heat released in combustion of hydrocarbons has enormous and far reaching implications.
The first implication is that the thermodynamics of fossil fuel use and nuclear reactions removes all the arguments of the non-believers, skeptics or the deniers of global warming for political or financial reasons. The second implication is for a massive down-sizing of fossil fuel burning and a much more conservative approach to nuclear power stations in the future and a strong justification for using solar energy to power the future energy needs of people.
If Nordell and his school are correct there is no such thing as clean coal as the heat of combustion and the energy cost of liquefaction of carbon dioxide for land fill sequestration add to the global thermal load. The definition of renewable energy must be redefined to include the embedded energy requirements of all such systems. For biofuel this includes the heat generated in crop production and construction of distilleries/mills and transport and, where applicable, in forest clearing and avoidance of pollution. For solar energy (sunlight, wind and wave power) it includes the energy expended in infrastructure including the manufacture of the solar panels, wind mill turbines, power lines and support structures. Smil (2010) has recently drawn attention to the high energy costs of steel manufacture and its absolute dependency on burning coke (produced from coal). One billion tonnes of steel are manufactured annually requiring the burning of about 620 million tonnes of coal. The concept of accelerated dependency on “renewable energy” will require an enormous increase in infrastructure that requires steel resulting in an even greater need to burn coal If the concepts of Nordell and others are correct- that heat energy from hydrocarbons is a greater cause of global warming than greenhouse gases, then clean coal or coke is of little extra value. The heat emissions theory also rules out nuclear power as a future clean energy source especially as it has huge dependency on energy from mining of ore to the manufacture of uranium dioxide and construction and decommissioning of the power plants themselves and their permanent security needs in addition to the heat from nuclear fission
Heat emissions theory also de-emphasizes the roles of atmospheric methane and nitrogen oxides but it is important to keep in mind that some 26% of global warming is still from gaseous pollution and could be underestimated (see Chaisson 2008).The need is to reduce the burning of fossil fuels. This will be forced upon the world as hydrocarbon sources are depleted but there will be a dependency on fossil fuels far into the future. This will be catastrophic as the energy returned on energy expended for fossil fuels decreases as more “difficult to extract “oil replaces the “easily accessible” oil as occurs following the onset of Peak Oil (see the changes that have occurred with the EROI for oil in the USA since the discovery of oil [Figure 1]).
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Figure 1. Barrels of oil produced relative to the barrels of oil used to get, deliver, and use that oil in the USA(Hall 2009).The low value of 3:1 is for the USA where Peak Oil arrived many years ago and they are now “scraping the barrel” to extract the remnants of oil provinces. For world oil the value was 35:1 in the 1900s falling to 20:1 at the present time with further decline to come as the time of Peak Oil is exceeded. |
This means that it now takes ~20 “quads” to yield the useable energy from oil that was once got in 1 quad or for every barrel of crude oil available for industry about 20 times more CO2 and heat are generated then in the early days of oil exploitation (Hall 2009 ).
The research of Bo Nordell and Bruno Gervet invokes the first law of thermodynamics, but the complexity of the calculations of the sources of heat on the planet is such that a great deal more modeling of the heat produced in burning hydrocarbons, and in nuclear reactions, is needed before we can have a more precise partitioning of the sources of the heat. It appears that one major point has been made and that is “that the heat generated when fossil energy is used to accomplish work was not accounted for(or not considered sufficiently large to be included) in previous global warming calculations”.
If it is verified that heat from the burning of fossil fuel is a major contributor to global warming then a different set of priorities emerges and research and energy policies should be redirected. Nordell and Grevet assign 74% of present day global warming to the burning of fossil fuels but another eminent scientist Eric Chaisson of Tufts University (Chaisson 2008) argues the same scenario but with a much lower proportion of global warming contributed by heat emissions to date, describing it as indiscernible but that it could grow substantially in the future. He argues that with the world continuing in a business as usual manner, that the world has an unavoidable global heating from the burning of non-renewable energy sources and harnessing of nuclear and geothermal power, of 30C which could develop within 300 years. This increase in temperature does not include any warming effects of the green house gases released over that time. A 30C temperature rise, according to the Intergovernmental Panel on Climate Change, is the tipping point for massive climate change. There is an urgent need for further research to confirm or otherwise the Nordell school’s research.
Budyko M I 1969 The effect of solar radiation variations on the climate of the Earth, Tellus 21, 611–619
Chaisson E J 2008 Long-term Global Heating from Energy Usage, Eos transactions of the American Geophysical Union 89 (28): 253
Hall C A S 2009 Peak Oil, Energy return on investment and your financial future. 2nd Biophysical Economics Conference. http://web.mac.com/biophysicalecon/iWeb/Site/BPE%20Conference_files/Download%20Hall.pdf
Hall C A S, Balogh S and Murphy D J R 2009 What is the Minimum EROI that a Sustainable Society Must Have? Energies 2: 25-47; doi:10.3390/en20100025 http://www.mdpi.com/1996-1073/2/1/25/pdf
Nordell B and Gervet B H 2009 Global energy accumulation and net heat emissions. International Journal of Global Warming 378-391
Smil V 2010 The Iron Age and Coal-based Coke: A Neglected Case of Fossil-fuel Dependence. http://masterresource.org/2009/09/a-forgotten-case-of-fossil-fuel-dependence-the-iron-age-requires-carbon-based-energy-like-it-or-not
Received 3 February 2010; Accepted 3 March 2010; Published 1 April 2010
