This is a sad hoax, for industrial man no longer eats potatoes made from solar energy; now he eats potatoes partly made of oil. (Howard T Odum)
There are only three primary energy sources on earth, solar energy, the gravitation of the sun and the moon and the geothermal energy. Of these, solar energy is completely dominating. These primary forms are the origin of all the secondary forms; biomass (from photosynthesis); circulation of water (which allows us to extract hydro-electricity); the wind; tidal flows and geological processes (volcano eruption, erosion, earthquakes etc.) The primary and secondary energy sources that formed the oil, photosynthesis, geological movements and geothermal energy are all diluted and difficult to use. But they have had a very long time to create a very concentrated product, which can be extracted for a low cost and be the basis for other energy carriers, such as electricity and petrol. It is the great “work” of the bio-geosphere that has created the energy intensity of oil compared to the original biomass.
Energy has been central for the dramatic increase of productivity of human labour. The tremendously improved, and thereby cheaper, transport that resulting from cheap oil is a key driver in the globalization of our economy and of our life. The economic importance, and the implications, of this largely surpass the importance of the World Trade Organization (WTO) and the EU and other free trade agreements, or possibly one could even say that they are a result of energy use[1]. Despite us living in an industrial society, or as some claim, an information society, agriculture is still very important and the interaction between energy and agriculture has major implications as oil reserves dwindle. It works both ways. It is largely through the use of external energy that labour productivity in farming has increased. On the other hand, historically and ecologically, agriculture was supposed to deliver more energy than it consumed. That was the whole point of farming in the first place. But agriculture of today, and even worse our food system at large, is a huge net consumer of energy. At the same time, expectations are that we will produce more biomass and energy from farming. Those are the reasons for why this chapter discuss the energy and agriculture nexus thoroughly.
Energy costs represent some 3 percent of GDP. This fact can lure us into believing that energy is not so important for our economy. But nothing could be more wrong. Water costs are almost negligible and still most of our economy would collapse if there was no water, well all of it would collapse. If the 3 percent energy costs are taken away, most of the other 97 percent will vanish. Cheap energy, mainly in the form of fossil fuel, is the fuel of our whole economy, all things would grind to halt, like a car without petrol without it. This is also realised by many, even if most politicians try to do a balancing act of overplaying our ability to find other solutions and underplaying our extreme dependency of fossil fuel. It is like we found an enormous bag of candy that someone left, and we just eat and eat. How important energy is, is also reflected in the substantial subsidies that are directed to fossils fuel, which are calculated by IEA to US$ 650 billion in 2008 (UNEP 2011)
Energy use and supply
Since the first oil crisis in the mid 1970s, the energy consumption per capita in high income countries has stagnated. Transport energy is an exception and has almost doubled in the high income countries. Globally, the supply of energy has doubled in the same period. The transportation sector accounts for over a quarter of total world energy use, and the proportion has increased since 1973. Cars, trucks and air transport take most of the transport energy; in the EU, road transport represents 82% and air transport represent 14% of the transport energy. Transport of people both for work and for leisure increase dramatically as people become wealthier. A flight from England to Mallorca was a big thing, and very costly in the 1960s, now it is almost like catching a bus, and would be a lot more so if it weren’t for all the security measures. Unless there is a major shift away from current patterns of energy use, world transportation energy use is expected to grow at 2% per year, with energy use 80% above 2002 levels by 2030 (UNEP 2009, IEA 2009, EU 2010).
With increasing awareness about problem with climate and political and economic uncertainties about oil and gas supplies there is a renewed interest in bio-energy and renewable fuels. It should be noted that the supply of energy from biomass is double the supply of energy from nuclear power and that in developing countries biomass represents a much higher proportion than in the high-income countries. Still fossil fuel represents 80 percent of all supplied energy as can be seen from the graph below.
The energy input per GDP unit is decreasing in most countries and, perhaps surprising, most in China.
The poorest people have very limited access to energy; it is largely limited to firewood that is collected by household members, often women and children, manure or other combustible waste products[2]. Approximately 2.6 billion people live with these as their main energy source (UNIDO 2008). There is a strict energy hierarchy for household energy in the sense that with increasing income people move from wood to coal (charcoal or mineral coal), kerosene, PNG and finally electricity. Around 1.6 billion people have no access to electricity. Apart from the comfort and health advantages of electrical light compared to kerosene or firewood, electrification can lead to substantial economic development. In the Philippines, it is estimated that electrification of the rural areas would have a value of between 81 and 150 dollars per household per year. More than any other factor, access to energy can explain the difference in productivity between poor and rich.
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