Energy Sources and the Situation of Natural Gas in Italy

CHAPTER 1 A GENERAL VIEW ON ENERGY SOURCES Italian energy balance For energy balance we identify the instrument with which the quantities offered and those demanded of energy sources are contrasted in a specific area (normally a country, but sometimes also aggregates or parts of a country) with reference to a specific period of time (normally a year). Compared to partial balances, that register the offer and demand of only one energy source, energy balance let get the point of interdependence relations among the individual energy sources. Adopting a non-restrictive criterion on the construction of energy balance, this must calculate the all energy used, both self-produced and bought, both coming from a stock source and flow-source. But this construction gives also some problems relative to: • Lack of reading of some quantities employed that in this way they must be estimated with great margins of doubt; • Uncertain definition of the limit within we can calculate the exploitation of natural flows. For example the passive solar energy (partial heating of houses and greenhouses or drying of food farming products, etc...). In practise energy balances made by national and international organizations are between the two sides even if they approach to the first one, they generally include the quantities commercialized 1 . Italian energy balance formulated by Ministry of Industry has been published for the first time on 1953, it is composed by out-and-out energy balance, four attachments and a summary balance, and it is presented both in metres and Kcal. Primary energy sources are the principal object of energy balance, that’s those ones present in nature before having undergone any change and they can be classified as follows: • Fossil sources: oil, carbon and natural gas; • Nuclear source: fission (uranium, thorium), fusion (deuterium, tritium); • Renewable sources: classical ones (hydroelectric power, heat energy) and new ones (wind power, solar power (heat, photovoltaic), fuel from waste (CDR), biomass (firewood), bio fuels (bio ethanol, biogas). Primary energy sources cannot be replaced between them, because they have different intrinsic characteristics that concern: the kind of energy deliverable, specific power, scale of plants, availability, supply costs, transformation costs, environmental impact and assigned risks 2 . It’s possible to note that from the nineties to nowadays Italian energy balance has presented some interesting variations, in fact comparing 1992 and 2004 summary balances in Italy, there are some differences easily detectable. The production of solid fuels, which in 1992 amounted to 1,451 Mtoe, in 2004 decreased to 0,556 Mtoe, even the production of gas decreased from 14,738 Mtoe to 10,693 Mtoe, while on the contrary oil production increased from 4,501 Mtoe to 5,445 Mtoe. Surely import variations are very important; suffice it to consider that in 1992 Italy imported 28,316 Mtoe of gas against 56,024 Mtoe in 2004 showing a very high dependence for supply from foreign countries. In fact, the lack of availability of energy sources and the absence of nuclear energy involve one of the lowest self-sufficiencies in Europe for Italy, equal to 15,8% of national requirement. The analysis of the trend of last fifteen years of primary energy sources demand highlights a substantial increase of 1 Source (L. De Paoli, 1998/1999, Il bilancio e le altre forme di contabilità energetica). A 2 Source (L. De Paoli, 1998/1999, Il bilancio e le altre forme di contabilità energetica). B 3