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UNESCO Desire – Net project Sustainable Development Pietro La Mendola

UNESCO Desire – Net project Sustainable Development Pietro La Mendola pietro.lamendola@casaccia.enea.it UNESCO Rome, 2007 5-19 February. HOW DEVELOPMENT IS DEFINED AS “SUSTAINABLE”? and WHAT IS THE ENERGY ROLE ?. HOW DEVELOPMENT IS DEFINED AS “SUSTAINABLE”?(IPCC).

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UNESCO Desire – Net project Sustainable Development Pietro La Mendola

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  1. UNESCO Desire – Net project SustainableDevelopment Pietro La Mendola pietro.lamendola@casaccia.enea.it UNESCO Rome, 2007 5-19 February



  4. SUSTAINABLE HUMAN ACTIVITIES Some requirements of the so-called “sustainable” or “eco-efficient” activities are: Prevention of negative environmental behaviours; Reversibility of changes on the environment;

  5. SUSTAINABLE HUMAN ACTIVITIES The possibility of putting anew the materials used in the technological processes in the environment at the end of the cycles; Multiple “cascade” use of materials and different forms of energy that deal with the process, with the aim of obtaining a decrease in the size of the transformations.

  6. DOES ENERGY DISAPPEAR? Energy can not be created nor destroyed Words as “production” or “consumption” of energy, often used by technicians, are not correct and misleading.

  7. ENERGY CAN BE TRANSFORMED We are able only to design, make or use tools which transform energy into a different form Words as “renewable”, “inexhaustible” or “clean” and so on, have been often used to describe new technologies regarding energy transformation

  8. ENERGY AND NEW PROCESSES The progress of science promotes processes which transform the energy in a more efficient way Nonetheless, the total demand of energy to be transformed is increasing, as well as the number of potential users.

  9. PROBLEMS OF “NON - SUSTAINABILITY” Exhaustion of materials because they are non renewable; Desertification of some large regions, and as a result, quickly alteration of local climate; Extinction of animal and vegetal species, or decrease of related population.

  10. In the last decades, the attention has being focused on the effects that energy models, based on the uncontrolled abuse of burning, can cause to the evolution of distribution of climatic zones in our planet. The illusion about regularity and immutability of climate is due to the short life of human being in comparison with the age during which climatic phenomena usually evolve. DEVELOPMENT AND VARIABILITY OF EARTH CLIMATE

  11. We are not surprised if we find out, in the same geographic area and in different beds, fossils of animals and plants which are typical of savannahand polar climate animals. Observations of solar activities have pointed out that sun energy on Earth is subject to relevant variations of intensity depending on explosive phenomena of enormous proportions. DEVELOPMENT AND VARIABILITY OF EARTH CLIMATE

  12. Mitigation Anthropogenic Climate Change (IPCC) Climate Change Impacts Socio-Economic Development Paths Emissions

  13. The main worry is from the risk of introducing, through human activities, a perturbation in well- balanced systems, but under conditions of “maximum”, compared to the sum of all forms of stored energy. RISK OF INSTABILITY

  14. According to the pessimistic hypothesis, these perturbations could affect the earth energy systems, that we are not able to describe mathematically for all possible interactions, leading them to conditions of progressive instability. RISK OF INSTABILITY

  15. This event could cause effects of divergent sizes, not proportional to the causes which have produced them, or even phenomena like “dominoes” acting in unforeseeable directions. RISK OF INSTABILITY

  16. “Average temperature” would be a definable value if domain and moment were indicated calculating the mean. But temperature does not count the energy stored in the earth biosphere, for the following important elements: GLOBAL WARMING AND “GREENHOUSE” EFFECT

  17. latent energy of fusion and vaporisation atmosphere pressure kinetic energy of air and sea waves wave and tide motion elevation saline unbalance GLOBAL WARMING AND “GREENHOUSE” EFFECT

  18. Old and modern greenhouses working is based on solid panel able to transmit the radiant energy and to stop the transmission of the heath carried by the air convective motions. Nothing alike occurs in the earth’s atmosphere, where, except the mountains, there are no solid screens, and the motion of the mixture of gasses, solids and fluids constituting the air is unceasingly supplied through large amounts of energy. GREENHOUSES AND GREENHOUSE EFFECT

  19. The considerable attenuation of thermal shocks caused by solar radiation, occurring in the surface of heavenly bodies without atmosphere, is due to a large number of mechanical, thermodynamic and thermo kinetic phenomena, among those the most important seem to be closely linked to water phase changes and to the stored energy as latent heat of vaporisation. GREENHOUSES AND GREENHOUSE EFFECT

  20. In climatic environments where the relative humidity is very low, in fact, very high day-night temperature ranges occur making animal and vegetal life hard. The stabilising effect of atmospheric water is known even if it is not easy to calculate. In the vapour phase water is quite transparent through solar radiation in visible and thermal spectrum. In the solid microcrystallinephase reflects the most of thermal radiation. GREENHOUSES AND GREENHOUSE EFFECT

  21. The daily transparency and night cloudiness enable the storage of solar energy in the atmosphere and the following energy conversions. CO2 of atmosphere can not work through the same physical schema because: It is a very heavy gas stagnating near the ground. It has a very low solidification temperature being not easy to reach, in the quota where it is. It is in the atmosphere in little concentrations in comparison with water GREENHOUSES AND GREENHOUSE EFFECT

  22. CO2 is supposed acting through the selectivity of its range of emission - absorption that could let go higher frequency than solar radiation and terrestrial reflection, absorbing and turning the lowest frequency into thermal energy. We must say that carbon being on Hearth, through the CO2 component of the atmosphere, takes part in a lot of processes, one correlated to another, and not all of them are well known. GREENHOUSES AND GREENHOUSE EFFECT

  23. Growth rate of vegetation will be higher if CO2 atmosphere content increases Each hectare of land changed to desert puts on the atmosphere thousands of tons of CO2 INCREASING OF CO2

  24. The metabolism of living organisms The vegetal life cycle and creation - destruction of humus The animal life cycle; production and disappearance of carbonates. For example coralline barriers. The mineral cycle of equilibrium carbonates - bicarbonates The equilibrium of solubility of CO2 in terrestrial waters depending on temperatures All combustions of material of living source and mineral reactions. INCREASING OF CO2

  25. Fossil combustions and mineral dissociations introduce into the atmosphere a kind of different CO2, which can be distinguished from the one coming from other cycles, thanks to the absence of the C14radioactive component because of decay. Measures, aiming at highlighting the contribution of human activities in the increasing CO2 in the atmosphere, did not result successful, probably for the quantitative ratio with other exchange processes. CO2, AND RADIOACTIVE C14

  26. Carbon sinks and the carbon cycle

  27. Terrestrial ecosystems play an important role in the global carbon cycle. Around one-third of global anthropogenic carbon emission in the past one hundred fifty years resulted from land-use change, namely forest clearing in the tropics and elsewhere. Carbon sinks and the carbon cycle

  28. On an annual global basis, land-use change results in emissions of 1.6 + - 0.8 giga tonnes of carbon (GtC). This account for around 25 % of emissions from fuel combustion and cement production. Carbon sinks and the carbon cycle

  29. These and other findings were assessed by the UNEP/World Meteorological Organisation (WMO) Intergovernmental Panel on Climate Change. Its Special Report, published in 2000, concluded that land-use change, and forestry can contribute to the reduction of greenhouse gas emissions by avoiding deforestation and increasing carbon uptake through afforestation, reforestation and improved management of forests, crops and grasslands. Carbon sinks and the carbon cycle

  30. The strategy, or often the strategy absence, in the energy field, on which the economic politics of powerful states of XIX and XX centuries have been based, has been founded on the convictions that dominated the ancient world: limitless economic scenario continuous and limitless discovery of new natural resources infinite ability of the environment to receive human waste ability to impose the price of raw materials THE PROBLEMS THAT FACES US ABOUT THE ENVIRONMENT AND THE ENERGY

  31. The economists and the scientists will have to begin to communicate correctly among them and will have to try to travel through new roads. The public opinion of all the nations, that have elective governments, currently have a greater sensibility to the environment than they had in past times and it can influence the choices of the governments ENVIRONMENT FOUNDED PARTIES

  32. Many international movements of opinion ask the governments to adopt environment political measures, oriented to cancel the modifications produced by mankind. The result of these provisions would be the restoration of the previous environmental conditions. TO RESTORE THE NATURAL ATMOSPHERE. WHAT AGE?

  33. What we consider natural environment, because it is previous to the current excessive use of energy conversions, it often was already deeply modified by human presence as well as through natural phenomena. A correct approach is trying to achieve goals for planned modifications of the territory. It is hoped for consequences of the modifications in the long term which are foreseen and that we are able to correct the errors. TO RESTORE THE NATURAL ATMOSPHERE. WHAT AGE?

  34. The prevailing definition of sustainability of the energy conversions is founded currently on the hypothesis of the modification of the distribution of climates in the Earth for effect of the excess of gaseous emissions in the atmosphere. ENERGY WITHOUT GAS EMISSIONS

  35. In particular are seen in way negative the energetic processes in which fossil fuels are burnt: fossil coal, oil, methane. Since many scientists think that the nature is not able to recycle with biological processes in short time the excess of inorganic carbon emitted in form of CO2 by means of these combustions of uncontrollable diffusion ENERGY WITHOUT GAS EMISSIONS

  36. The conversions that use the energies from solar, wind, hydraulic origin, and, with opportune limits, the combustions of short cycle organic material (biomasses) satisfy this requirement because they do not produce immediate and directed emissions of CO2 in the atmosphere or produce equivalent removal of it. The precaution principle demands careful analysis of the energetic cycle and of its impact on the environment. ENERGY WITHOUT GAS EMISSIONS

  37. It is not possible converting energy without degrading a part of it into a so low temperature heat that it cannot be used anymore. On the other hand, the high enthalpy energy tends to be converted spontaneously and therefore every form of accumulation always is a danger. The greater is danger, the larger is the amount of accumulated energy and the higher is the enthalpy. ENERGY CONVERSION ONLY IF NECESSARY

  38. We can consider: large hydroelectric river basins at a high altitude large deposits of combustible materials big tanks of high pressure compressed gasses etc. The most prudent behaviour about the energy problems is to help the use of kind of energy fitting to the aims and to resort to the conversion when it is the only solution. ENERGY CONVERSION ONLY IF NECESSARY

  39. For example, the use of the energy as electricity is reasonable for: Motors Lighting system Communications Computer science ENERGY CONVERSION ONLY IF NECESSARY

  40. On the contrary, it is not justified resorting to a cycle including the conversion of high temperature heat in electricity, losing beyond 60%, in order to make a second conversion in a low temperature heat: For example: electrical water heaters electrical stoves ENERGY CONVERSION ONLY IF NECESSARY

  41. A different budget can be made when the energy as electricity is reconverted in order to realize thermodynamic cycles allowing to use heat supplies already available by raising the temperature. For instance, the heat pump systems of heating. Or electrical oven in comparison with those heated by fuel without thermal recovery like the gas kitchen oven. In cases as these, the conversion of the electricity in heat can be justified, since it takes part in a favourable total cycle. ENERGY CONVERSION ONLY IF NECESSARY

  42. The heat conversion in electrical energy has had a greater expansion than it was technically justifiable. Power stations have been built more and more powerful in the same place, because of: better efficiency for the scale factor difficulty to find new locations being favourable for the construction, especially for nuclear power stations lower expenses for the staff devoted to management On other hand, the constructions of single or few number systems have become too much expensive. CENTRALIZED OR DIFFUSE CONVERSION ?

  43. The hydroelectric plants, where energy conversion does not occur since the natural resource is already mechanical energy, are built in a position obliged by the hydro geologic situation. Often the big systems have deeply modified the territory. They force people to leave the flooded regions and they are not free from risks. The electric power coming from these plants in centralized way usually needs be distributed in far localities. CENTRALIZED OR DIFFUSE CONVERSION ?

  44. The convenience criteria about the transformations of solar or wind energy are opposite. The solar radiation has a power density of equivalent magnitude as one demanded for final use and it is very discontinuous. The wind energy has a greater power density, but it is characterized by extreme irregularity. CENTRALIZED OR DIFFUSE CONVERSION ?

  45. Any is the applied technology both these natural resources will become convenient if: The primary conversion occurs close to the place of the final use Accumulation of energy is obtained through small and distributed devices The final uses do not needs energy in continuous way Integration with energy from other sources is achievable. CENTRALIZED OR DIFFUSE CONVERSION ?

  46. The solar and wind low power systems and distributed in the territory also offer the advantage of being cheaper than those that are centralized, because they can be manufactured in series and in unified way. Moreover, they can be installed and managed by staff with modest technical qualification. In the current condition of technology, hardly it will become convenient converting the solar and wind energy in centralized way and distributing energies in the territory that are naturally already available in distributed way. CENTRALIZED OR DIFFUSE CONVERSION ?

  47. Many applications of the solar energy do not demand the conversion in mechanical energy otherwise realizing favourable and economic cycles. The solar energy has been for millennia used for the salt separation from the sea water through evaporation, because the valuable material was the salt and the technical knowledge allowed only this process. FROM SUN DRINKABLE WATER, CLIMATISATION AND ONCE-THROUGH COOLING

  48. Nowadays, in many places the precious material is the freshwater and efficient processes can be developed in order to obtain it from the sea. through photovoltaic cells and osmotic membranes through multiple stage evaporation process at low pressure The freshwater or feebly salt water for agricultural and alimentary use can easily be accumulated and distributed. It re-enters in the energetic resources of the type of entropy reduction. FROM SUN DRINKABLE WATER, CLIMATISATION AND ONCE-THROUGH COOLING

  49. Other human needs, which can be satisfied by the solar energy in disseminated modality without the phase of the conversion in electricity, are related to the air conditioning. The necessity to heat or to cool air in the buildings, thermally insulated from the outside, in order to obtain comfortable conditions for people or in order to conserve fresh goods, can be satisfied resorting to plants that take advantage of the solar heat, or directly or through refrigeration cycles. Systems of this type need for the construction and the management staff with basic technical knowledge. FROM SUN CLIMATISATION AND ONCE-THROUGH COOLING

  50. It is obligatory, even if we use the sources of energy defined renewable, operating with great precaution and respect for the nature. Taking hydraulic, solar and wind energy away can modify also deeply the atmosphere in which beings exist and they reproduce themselves. ATMOSPHERE MODIFICATIONS DUE TO TAKING ENERGY AWAY

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