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Posts Tagged ‘κλιματικές αλλαγές

Ηλεκτρικά αυτοκίνητα και κλιματική αλλαγή

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Electric Vehicles are not a Panacea for Climate Change

from: http://www.cesifo-group.de/ifoHome/presse/Pressemitteilungen/Pressemitteilungen-Archiv/2019/Q2/pm_20190417_sd08-Elektroautos.html

Apr 17, 2019

Electric vehicles will barely help cut CO2 emissions in Germany over the coming years, as the introduction of electric vehicles does not necessarily lead to a reduction in CO2 emissions from road traffic. Natural gas combustion engines are the ideal technology for transitioning to vehicles powered by hydrogen or “green” methane in the long term.

Considering Germany’s current energy mix and the amount of energy used in battery production, the CO2 emissions of battery-electric vehicles are, in the best case, slightly higher than those of a diesel engine, and are otherwise much higher. This has been confirmed by a new study by Christoph Buchal, professor of physics at the University of Cologne; Hans-Dieter Karl, long-standing ifo energy expert; and Hans-Werner Sinn, former ifo president and professor emeritus at Ludwig-Maximilians-Universität München. The researchers carried out their detailed calculations using the concrete examples of a modern electric car and a modern diesel vehicle. In addition to CO2 emissions from battery production, they looked at alternative energy sources for electricity in order to calculate the impact electric vehicles have on CO2 emissions. They show that even with today’s technology, total emissions from a combustion engine powered by natural gas are already almost one-third lower than those of a diesel engine. “Over the long term, hydrogen-methane technology offers a further advantage: it allows surplus wind and solar power generated during peaks to be stored, and these surpluses will see a sharp increase as the share of this renewable energy grows,” Professor Buchal explains.

In their study, the authors criticize the fact that EU legislation allows electric vehicles to be included in calculations for fleet emissions with a value of “zero” CO2 emissions, as this suggests that electric vehicles do not generate any such emissions. The reality is that, in addition to the CO2 emissions generated in the production of electric vehicles, almost all EU countries generate significant CO2 emissions from charging the vehicles’ batteries using their national energy production mixes. The authors also take a critical view of the discussion about electric cars in Germany, which centers around battery-operated vehicles when other technologies also offer great potential: hydrogen-powered electric vehicles or vehicles with combustion engines powered by green methane, for instance. “Methane technology is ideal for the transition from natural gas vehicles with conventional engines to engines that will one day run on methane from CO2-free energy sources. This being the case, the German federal government should treat all technologies equally and promote hydrogen and methane solutions as well,” emphasizes Professor Sinn.

Publication (in German)

  1. Buchal, Christoph, Hans-Dieter Karl and Hans-Werner Sinn, «Kohlemotoren, Windmotoren und Dieselmotoren: Was zeigt die CO2-Bilanz?», ifo Schnelldienst 72 (08), 2019, 40–54 | Details | PDF Download


Prof. Dr. Dr. h.c. mult. Hans-Werner Sinn

ifo Institute
Phone: +49(0)899224-1279
Fax: +49(0)899224-1901
Email: sinn@ifo.de

σχετικά και στο Έκθεση αποκάλυψη: Τα ηλεκτρικά αυτοκίνητα εκπέμπουν περισσότερο CO2 απ’ τα πετρελαιοκίνητα! ( δημοσιευμένο στο https://igata.gr/2019/05/04/ta-ilektrika-aytokinita-ekpempoun-perissotero-co2/?fbclid=IwAR1sCv4agy4dz_WtU6uLYq-FJflggcLgnFRRJWXe7GFkdhNdJWIOhpiOhco)

Για το θέμα ιδιαίτερο ενδιαφέρον έχει το σχόλιο στο fb του Apostolos Efthymiadis

Για το ἐνεργειακό μείγμα τῆς χώρας μας, τα πράγματα εἶναι ἀκόμα χειρότερα ὄπως ἀποδεικνύεται στην συνέχεια.

Γενικότερα η κατανάλωση μίας κιλοβατώρας θα προκαλέσει τις ἐξῆς ἐκπομπές CO2 ἀνά μορφή ἐνέργειας :

Πετρέλαιο : 0,264 kg CO2/kWh
Ηλεκτρική ενέργεια: 0,989 kg CO2/kWh (κατά ΚΕΝΑΚ για Ἐλλάδα)

Mε βάση την ἔκθεση 2017 ἀπό το «Σύμφωνο τῶν Δημάρχων» http://publications.jrc.ec.europa.eu/…/jrc_technical…)

Ηλεκτρική ενέργεια: 0,81 kg CO2/kWh (για Ἐλλάδα )
Ηλεκτρική ενέργεια: 0,658 kg CO2/kWh (για Γερμανία)

Δια την παραγωγή μηχανικοῦ ἔργου μίας κιλοβατώρας για την ὤθηση τοῦ αὐτοκινήτου καὶ με μία μέση ἐνεργειακή ἀπόδοση ἐνός ντηζελοκινητήρα περί το 35% αὐτο συνεπάγεται ὄτι θα χρειαστούν 1/0,35 = 2,86 kWh καυσίμου και ἐπομένως θα ἔχουμε ἐκπομπή CO2 = 2,86 (0,264) = 0,75 κιλῶν διοξειδίου τοῦ ἄνθρακα.

Δια την παραγωγή ἰδίου μηχανικοῦ ἔργου μίας κιλοβατώρας για την ὤθηση τοῦ αὐτοκινήτου καὶ με μία μέση ἐνεργειακή ἀπόδοση μίας μπαταρίας στο 75% (δηλαδή με ἀπώλειες τοῦ κύκλου φορτίσεως/ἐκφορτίσως κατά 25%) συνεπάγεται ὄτι θα χρειαστούν για την φόρτιση των μπαταριῶν 1/0,75 = 1,33 kWh ἠλεκτρικῆς ἐνέργειας, οι ὀποῖες με την σειρά τους θα προκαλέσουν ἐκπομπές 1,33 (0,989) = 1,32 κιλῶν διοξειδίου τοῦ ἄνθρακα, δηλαδή αὐξημένες ἐκπομπές κατά 57,3 % ἔναντι τοῦ ντηζελοκινητήρα!!!

Ἐάν ἀντί τοῦ συντελεστοῦ 0,989 ληφθῇ ο συντελεστής 0,658 kg CO2/kWh τότε ἀντίστοιχες οι ἐκπομπές ὑπολογίζονται ἴσες με 1,33(0,658) = 0,86 kgCO2/kWh δηλαδή ἐπίσης ὑψηλότερες (κατά 17%) ἔναντι τῶν πετρελαιοκινητήρων.

Ἐδῶ ἡ ἀπάτη εἶναι καταφανῆς ἐνῶ οι ἀργυρόνυτοι γραφειοκράτες τῶν Βρυξελλῶν ἔχουν πλέον νομοθετήσει την ὑποχρεωτική ἐγκατάσταση σταθμῶν φορτίσεως ἠλεκτρικῶν αὐτοκινήτων σε νέες και παλαιότερες οἰκοδομές (Ὀδηγία 2018/844/ἘΚ).

James E. Hansen και global warming

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[Π&Π: το ακόλουθο είναι ίσως το πρώτο άρθρο που δημοσιεύθηκε, στις 24/6/1988, σε μεγάλης κυκλοφορίας έντυπο, τους ΝΥΤ και παρουσίασε την άποψη ότι η υπερθέρμανση του πλανήτη-κλιματική αλλαγή είχε ήδη ξεκινήσει]

Global Warming Has Begun, Expert Tells Senate

The earth has been warmer in the first five months of this year than in any comparable period since measurements began 130 years ago, and the higher temperatures can now be attributed to a long-expected global warming trend linked to pollution, a space agency scientist reported today.

Until now, scientists have been cautious about attributing rising global temperatures of recent years to the predicted global warming caused by pollutants in the atmosphere, known as the »greenhouse effect.» But today Dr. James E. Hansen of the National Aeronautics and Space Administration told a Congressional committee that it was 99 percent certain that the warming trend was not a natural variation but was caused by a buildup of carbon dioxide and other artificial gases in the atmosphere.

Dr. Hansen, a leading expert on climate change, said in an interview that there was no »magic number» that showed when the greenhouse effect was actually starting to cause changes in climate and weather. But he added, »It is time to stop waffling so much and say that the evidence is pretty strong that the greenhouse effect is here.» An Impact Lasting Centuries

If Dr. Hansen and other scientists are correct, then humans, by burning of fossil fuels and other activities, have altered the global climate in a manner that will affect life on earth for centuries to come.

Dr. Hansen, director of NASA’s Institute for Space Studies in Manhattan, testifed before the Senate Energy and Natural Resources Committee.

He and other scientists testifying before the Senate panel today said that projections of the climate change that is now apparently occurring mean that the Southeastern and Midwestern sections of the United States will be subject to frequent episodes of very high temperatures and drought in the next decade and beyond. But they cautioned that it was not possible to attribute a specific heat wave to the greenhouse effect, given the still limited state of knowledge on the subject. Some Dispute Link

Some scientists still argue that warmer temperatures in recent years may be a result of natural fluctuations rather than human-induced changes.

Several Senators on the Committee joined witnesses in calling for action now on a broad national and international program to slow the pace of global warming.

Senator Timothy E. Wirth, the Colorado Democrat who presided at hearing today, said: »As I read it, the scientific evidence is compelling: the global climate is changing as the earth’s atmosphere gets warmer. Now, the Congress must begin to consider how we are going to slow or halt that warming trend and how we are going to cope with the changes that may already be inevitable.» Trapping of Solar Radiation

Mathematical models have predicted for some years now that a buildup of carbon dioxide from the burning of fossil fuels such as coal and oil and other gases emitted by human activities into the atmosphere would cause the earth’s surface to warm by trapping infrared radiation from the sun, turning the entire earth into a kind of greenhouse.

If the current pace of the buildup of these gases continues, the effect is likely to be a warming of 3 to 9 degrees Fahrenheit from the year 2025 to 2050, according to these projections. This rise in temperature is not expected to be uniform around the globe but to be greater in the higher latitudes, reaching as much as 20 degrees, and lower at the Equator.

The rise in global temperature is predicted to cause a thermal expansion of the oceans and to melt glaciers and polar ice, thus causing sea levels to rise by one to four feet by the middle of the next century. Scientists have already detected a slight rise in sea levels. At the same time, heat would cause inland waters to evaporate more rapidly, thus lowering the level of bodies of water such as the Great Lakes.

Dr. Hansen, who records temperatures from readings at monitoring stations around the world, had previously reported that four of the hottest years on record occurred in the 1980’s. Compared with a 30-year base period from 1950 to 1980, when the global temperature averaged 59 degrees Fahrenheit, the temperature was one-third of a degree higher last year. In the entire century before 1880, global temperature had risen by half a degree, rising in the late 1800’s and early 20th century, then roughly stabilizing for unknown reasons for several decades in the middle of the century. Warmest Year Expected

In the first five months of this year, the temperature averaged about four-tenths of a degree above the base period, Dr. Hansen reported today. »The first five months of 1988 are so warm globally that we conclude that 1988 will be the warmest year on record unless there is a remarkable, improbable cooling in the remainder of the year,» he told the Senate committee.

He also said that current climate patterns were consistent with the projections of the greenhouse effect in several respects in addition to the rise in temperature. For example, he said, the rise in temperature is greater in high latitudes than in low, is greater over continents than oceans, and there is cooling in the upper atmosphere as the lower atmosphere warms up.

»Global warming has reached a level such that we can ascribe with a high degree of confidence a cause and effect relationship between the greenhouse effect and observed warming,» Dr. Hansen said at the hearing today, adding, »It is already happening now.»

Dr. Syukuro Manabe of the Geophysical Fluid Dynamics Laboratory of the National Oceanic and Atmospheric Administration testified today that a number of factors, including an earlier snowmelt each year because of higher temperatures and a rain belt that moves farther north in the summer means that »it is likely that severe mid-continental summer dryness will occur more frequently with increasing atmsopheric temperature.» A Taste of the Future

While natural climate variability is the most likely chief cause of the current drought, Dr. Manabe said, the global warming trend is probably »aggravating the current dry condition.» He added that the current drought was a foretaste of what the country would be facing in the years ahead.

Dr. George Woodwell, director of the Woods Hole Research Center in Woods Hole, Mass., said that while a slow warming trend would give human society time to respond, the rate of warming is uncertain. One factor that could speed up global warming is the widescale destruction of forests that are unable to adjust rapidly enough to rising temperatures. The dying forests would release the carbon dioxide they store in their organic matter, and thus greatly speed up the greenhouse effect. Sharp Cut in Fuel Use Urged

Dr. Woodwell, and other members of the panel, said that planning must begin now for a sharp reduction in the burning of coal, oil and other fossil fuels that release carbon dioxide. Because trees absorb and store carbon dioxide, he also proposed an end to the current rapid clearing of forests in many parts of the world and »a vigorous program of reforestation.»

Some experts also believe that concern over global warming caused by the burning of fossil fuels warrants a renewed effort to develop safe nuclear power. Others stress the need for more efficient use of energy through conservation and other measures to curb fuel-burning.

Dr. Michael Oppenheimer, an atmospheric physicist with the Environmental Defense Fund, a national environmental group, said a number of steps can be taken immediately around the world, including the ratification and then strengthening of the treaty to reduce use of chlorofluorocarbons, which are widely used industrial chemicals that are said to contribute to the greenhouse effect. These chemicals have also been found to destroy ozone in the upper atmosphere that protects the earth’s surface from harmful ultraviolet radiation from the sun.

πηγή: https://www.nytimes.com/1988/06/24/us/global-warming-has-begun-expert-tells-senate.html?module=inline

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Φεβρουαρίου 6, 2019 at 9:54 μμ

Οι φυσικές διεργασίες του Φαινομένου του Θερμοκηπίου

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Φαινόμενο του Θερμοκηπίου – Οι Φυσικές Διεργασίες


Η αύξηση της θερμοκρασίας του πλανήτη (φαινόμενο θερμοκηπίου), θεωρείται ένα από τα σημαντικότερα προβλήματα περιβαλλοντικής υποβάθμισης σε επίπεδο παγκόσμιας κλίμακας, την τελευταία δεκαετία. Το πρόβλημα αυτό σχετίζεται με την κατάσταση της ατμόσφαιρας του πλανήτη. Για το λόγο αυτό είναι αναγκαίο να εξεταστούν κάποια θέματα που αφορούν στην ατμόσφαιρα του πλανήτη και στο πώς αυτή έχει εξελιχθεί μέσα στο χρόνο.

Η ατμόσφαιρα του πλανήτη αποτελείται κύρια από άζωτο και οξυγόνο. Περιέχει, όμως και άλλα αέρια σε χαμηλές συγκεντρώσεις, όπως το διοξείδιο του άνθρακα, το υποξείδιο του αζώτου, το μεθάνιο, το όζον και τους χλωροφθοροϋδρογονάνθρακες. Τα αέρια αυτά είναι τα πλέον κρίσιμα σε θέματα περιβαλλοντικής υποβάθμισης της ατμόσφαιρας. Οι συγκεντρώσεις τους στην ατμόσφαιρα μεταβάλλονται με ταχείς ρυθμούς λόγω ανθρωπίνων δραστηριοτήτων, με αποτέλεσμα τη δημιουργία πλανητικών φαινομένων, όπως το φαινόμενο του θερμοκηπίου και η αραίωση του στρατοσφαιρικού όζοντος.

Κατά τη δημιουργία της Γης πριν 4-5 δισεκατομμύρια χρόνια, πιθανά δεν υπήρχε καθόλου ατμόσφαιρα. Λόγω ηφαιστειακής δραστηριότητας, αέρια όπως το διοξείδιο του άνθρακα, υδρατμοί και διάφορες ενώσεις αζώτου και θείου, άρχισαν να εκλύονται διαχρονικά. Το μοριακό οξυγόνο της ατμόσφαιρας, θεωρείται ότι δημιουργήθηκε κύρια σαν προϊόν της φωτοσύνθεσης των φυτών που, αρχικά, εξελίχθηκαν ως υδρόβια και έτσι ήταν προστατευμένα από την βιολογικά καταστροφική έντονη υπεριώδη ακτινοβολία του ήλιου. Με την αύξηση του ατμοσφαιρικού οξυγόνου, υπήρξε μια παράλληλη αύξηση του όζοντος στη στρατόσφαιρα. Η απορρόφηση της υπεριώδους ακτινοβολίας από αυτό το όζον, επέτρεψε την εξέλιξη έμβιων όντων και στην ξηρά.

Ο πίνακας 1 παρέχει τη σύσταση «καθαρού», ξηρού αέρα και δεν περιλαμβάνει τις σχετικά μικρές αλλά ιδιαίτερα σημαντικές συγκεντρώσεις υδρατμών και ρύπων. Οι συγκεντρώσεις των περισσοτέρων χημικών ειδών που αναφέρονται στον πίνακα, παραμένουν διαχρονικά αναλλοίωτες, με εξαίρεση το διοξείδιο του άνθρακα που αυξάνεται περίπου 1,5 ppm (parts per million) ανά έτος. Αύξηση έχει παρατηρηθεί ακόμα στο μεθάνιο και το όζον.

Η ατμόσφαιρα αποτελείται από διάφορα στρώματα που διαφέρουν μεταξύ τους ως προς τη θερμοκρασία και άλλες παραμέτρους. Τα στρώματα αυτά από την επιφάνεια της γης, καλούνται κατά σειρά: τροπόσφαιρα, στρατόσφαιρα, μεσόσφαιρα και θερμόσφαιρα. Η εικόνα 1 δείχνει τη μεταβολή της θερμοκρασίας και της συγκέντρωσης του όζοντος, σαν συνάρτηση του υψομέτρου.

Ολόκληρο στο αρχείο:

Φαινόμενο του Θερμοκηπίου-Οι φυσικές διεργασίες (doc)

Φαινόμενο του Θερμοκηπίου-Οι φυσικκές διεργασίες (pdf)

[Κεφάλαιο από τα μαθήματα Εισαγωγή στο Περιβάλλον και Σύγχρονα Περιβαλλοντικά Προβλήματα Πλανητικής Κλίμακας του Πανεπιστημίου Αιγαίου]


Written by dds2

Δεκέμβριος 18, 2018 at 10:33 μμ

Το πρωτόκολλο του Κιότο

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Το Πρωτόκολλο του Kyoto

Το Πρωτόκολλο του Kyoto είναι η πιο σημαντική πρωτοβάθμια διεθνής συμφωνία για την καταπολέμηση της υπερθέρμανσης του πλανήτη. Πρόκειται για μια τροπολογία της UNFCCC και βασίζεται στη Συνθήκη Πλαίσιο για την Κλιματική αλλαγή που θεσπίστηκε στη Συνδιάσκεψη του Rio de Janeiro το 1992 και αποτελεί ένα πιο συγκεκριμένο και αυστηρό νομικό πλαίσιο από αυτή. Στόχος της Σύμβασης ήταν “η σταθεροποίηση των συγκεντρώσεων των αερίων του θερμοκηπίου στην ατμόσφαιρα, σε επίπεδα τέτοια ώστε να προληφθούν επικίνδυνες επιπτώσεις στο κλίμα από τις ανθρώπινες δραστηριότητες”.

Το Πρωτόκολλο, υπογράφηκε στις 11 Δεκεμβρίου του 1997 στο Kyoto της Ιαπωνίας (παλιά πρωτεύουσα της χώρας) και είναι σε ισχύ από τις 16 Φεβρουαρίου του 2005 μετά από την επικύρωσή του από την Ρωσία1 (για να γινόταν το Πρωτόκολλο διεθνής δεσμευτικός νόμος έπρεπε να επικυρωνόταν από ένα ορισμένο αριθμό χωρών, βλ σχετ. στην σημ. 1) και αποτελεί ουσιαστικά το πρώτο βήμα για την αντιμετώπιση της κλιματικής αλλαγής, ανοίγοντας τον δρόμο περαιτέρω πρωτοβουλιών για την αντιμετώπισή της.

Το πρωτόκολλο καλύπτει πλέον περισσότερες από 160 χώρες παγκοσμίως και πάνω από 55% των παγκόσμιων εκπομπών αερίων του θερμοκηπίου (βλέπε χάρτη 1). Η συνθήκη αυτή λήγει το 2012, ωστόσο διεθνείς συνομιλίες άρχισαν το Μάιο του 2007 σχετικά με μια μελλοντική συνθήκη που θα διαδεχθεί τη σημερινή.

Μόνο οι Ηνωμένες Πολιτείες, το Καζακστάν και λίγα ακόμη κράτη δεν έχουν επικυρώσει τη συνθήκη, με τις Ηνωμένες Πολιτείες να είναι ιστορικά η μεγαλύτερη πηγή εκπομπής αερίων θερμοκηπίου. Η Κίνα και η Ινδία, αν και εξαιρούνται από τις διατάξεις της ως αναπτυσσόμενες χώρες, έχουν επικυρώσει το Πρωτόκολλο του Κιότο. Η Κίνα μπορεί να έχει περάσει τις ΗΠΑ στις συνολικές ετήσιες εκπομπές αερίων του θερμοκηπίου σύμφωνα με κάποιες πρόσφατες μελέτες.

Με πράσινο χρώμα δηλώνονται οι χώρες που υπέγραψαν και επικύρωσαν το πρωτόκολλο, με κίτρινο όσες το υπέγραψαν και αναμένεται η επικύρωσή του, με κόκκινο οι χώρες που το υπέγραψαν αλλά δεν το επικύρωσαν και με γκρι χρώμα οι χώρες που δεν έχουν πάρει θέση.

Χάρτης 1. Συμμετοχή χωρών στο Πρωτόκολλο του Κιότο

(πηγή: ΒΙΚΙΠΑΙΔΕΙΑ και για ενημέρωση: http://el.wikipedia.org/wiki/%CE%91%CF%81%CF%87%CE%B5%CE%AF%CE%BF:Kyoto_Protocol_participation_map_2009.png )

Ένα από τα κυριότερα σημεία του Πρωτοκόλλου είναι το γεγονός ότι θέτει συγκεκριμένα όρια στις εκπομπές του CO2 που έχουν βρεθεί πως συμβάλλουν θετικά στη κλιματική αλλαγή.

Βάσει της συνθήκης πλαισίου για την Κλιματική αλλαγή, το Πρωτόκολλο του Kyoto διαχωρίζει τα κράτη ανάλογα με τη συμβολή τους στο φαινόμενο του θερμοκηπίου. Τα κράτη τα οποία θεωρείται ότι συνέβαλαν περισσότερο είναι τα κράτη – μέλη του ΟΟΣΑ, της ΕΕ-15 καθώς και 12 κράτη του πρώην Ανατολικού Μπλοκ με οικονομίες σε μετάβαση (Economy In Transition, EIT), μαζί με το Μονακό και το Λιχνενστάιν. Τα κράτη αυτά ονομάζονται κράτη του Παραρτήματος Ι.

Το Πρωτόκολλο δεσμεύει τα κράτη του Παραρτήματος Ι που έχουν κυρώσει την συμφωνία πλαίσιο και το Πρωτόκολλο του Kyoto, να μειώσουν το σύνολο  των εκπομπών τους κατά 5,2% σε σχέση με τα επίπεδα εκπομπών του 1990, για την πρώτη περίοδο δέσμευσης, το 2008 – 2012.

Η μείωση των εκπομπών των αερίων του θερμοκηπίου, αφορά ουσιαστικά έξι κύρια αέρια ή ομάδες αερίων του θερμοκηπίου, τα οποία είναι τα:

• Διοξείδιο του άνθρακα (CO2)

• Μεθάνιο (CH4)

• Υποξείδιο του Αζώτου (N2O)

• Υδροφθοράνθρακες (HFCs)

• Φωσφοροφθοράνθρακες (PFCs)

• Εξαφθορίδιο του θείου (SF6)

1 Ενενήντα μέρες μετά την επικύρωση του Πρωτοκόλλου και από τη Ρωσία ικανοποιήθηκαν πλέον και οι δύο απαραίτητοι όροι προκειμένου να τεθεί σε ισχύ το Πρωτόκολλο του Κιότο, δηλ. να έχει κυρωθεί τουλάχιστον από 55 κράτη- Μέρη της Σύμβασης για τις κλιματικές αλλαγές, και μεταξύ αυτών να συμπεριλαμβάνονται Μέρη του Παραρτήματος Ι της Σύμβασης (ανεπτυγμένες χώρες)  που αντιπροσωπεύουν τουλάχιστον το 55% των συνολικών εκπομπών διοξειδίου του άνθρακα των χωρών αυτών κατά το 1990.

Ολόκληρο στο αρχείο: ergM5E2

[το κείμενο προέρχεται από εργασία στο ΕΚΠΑ, στα πλαίσια του μαθήματος ΠΕΡΙΒΑΛΛΟΝΤΙΚΟ ΔΙΚΑΙΟ & ΝΟΜΟΘΕΣΙΑ-(401) -Εξέταση 2η – Απρ. 2010 – Θέμα 2: «Επιλέξτε μια από τις Διεθνείς Συμβάσεις ή από τα Πρωτόκολλα για την Προστασία του Περιβάλλοντος. Εντοπίστε πρόσθετα στοιχεία αναφορικά με την εφαρμογή της στην πράξη, τα ενδεχόμενα προβλήματα και την ενσωμάτωση της στην Ελλάδα»]

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Δεκέμβριος 17, 2018 at 8:29 μμ

Reducing CO2 emissions from the electric sector by the year 2030-policy recommendations (case study Greece)

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The case of Greece

Greece is a country of 131000 klm2 and 11 million people. But we must also keep in mind two more important facts: It’s a mountainous country, with 10000 villages, 3000 islands –100- inhabited. The islanders are almost 1 million people. The country also welcomes 25 million of tourists every year.
Αll of these people and places need energy. Steady, safe and cheap electric energy over a grid made and regulated through the public company of ΔΕH (DEI).

In 2014 the total energy production was 35,3 TWh (2000: 48,5 increased to in 2007: 53.9 and continuously decreasing since then).
The grid has to electrify an extremely big and difficult land (mountains and on the same time islands over an almost square side land with 1000 km diagonal).
The installed power is 12,8 GW (64% of the country’s total) (in 2010, it was 5,4 in 1980 and only 0,6 in 1960).
The flux of energy (installed capacity) is: 30% coal, 15% diesel, 15% natural gas, 20% hydroelectric, 10% renewables and others. According to 2013 data thermal units were10,060 GW, and the other units 7,222 GW.
When it comes to production the situation is follows: 55% from coal, 16% from diesel etc, 20% from natural gas and less than 10% from hydroelectric and renewables. So the installed capacity doesn’t mean that the end of fossil fuels production reaches an end. The price is about 41€/MWh.
Coal is extremely cheap, there is plenty of it in the country and the reserves are enough for 400 years. Because of economic crisis and memorandums the energy system is in a transition period towards privatization.

It is clear that electricity production basically comes from fossil fuels, coal, oil and natural gas. So a great problem of CO2 and other greenhouse gases has to be faced and controlled. There is also a great health impact. Some years ago there was a serious problem evening Athens. Air pollution (SO2, NOx, CO2) and PM were found in the city’s air. The regulations (closing near thermal units, unleaded gasoline etc) have made a progress. But in places like Ptolemaida (north Greece) or Megalopolis (south Greece) the problem is extremely serious, the lifespan is much shorter and cancer and lungs and cardiovascular diseases are increasing (more than double PM2.5 than the rest of the country, around 23 μg/m3) .
We must also take into account the obligations of the country because of international treaties and EC regulations for CO2 emissions and climate change.


The solution is not easy. If the aim is a better environment, in the year 2030, there must be a shift from a fossil fuels energy production to other safer for humans and the environment methods. But this is going to be very difficult for such a small time period (only 15 years). A 50% reduction of fossil fuels (practically almost 90% comes from fossil fuels nowadays) means that there must be a solution of an increase of not fossil methods to reach the capacity of about 20 TWh per year. The LCOE for natural gas in 2015 was around 19 /MWh. The LCOE for lignite in 2012 was 59,93 €/MWh because the energy density of Greek lignite (brown coal) is around 1.200kcal/kg. Unfortunately there isn’t an administration such as US EIA in Greece and the data comes from many different sources.

What can be the solutions?

Theoretically nuclear power, wind, solar, hydroelectric, bio-fuels etc.
But the answer isn’t so simple. The solution of nuclear power is impossible for Greece. The ecological movement and the left political parties of the country are not going to permit this solution. For them this subject is the holly grail of ecology for
Greece. They believe that this is very dangerous for a small and seismogenic country, with small distances from the probable location of a factory and populated cities etc.

Next solution is renewables.

Wind farms have been deployed during the last two decades all over the country. The installed capacity is 1558,2 MW. Medium price of wind energy in 2016: 98 €/MWh. Unfortunately with no respect to the landscape, the history, the use of land and the wild beauty of Greek natural environment. They have a great cost for construction and sometimes they are not connected to the grid. It seems that one the main reasons for their deployment is the big subsidies that companies and the owners can take from the state and the EC. Wind farms also sell the electricity 3-4 more expensive from the price of the fossil fuels production. I addition they cause problems to tourism, agriculture and animals breeding. Naturally all of these problems have started a big war against them from environmentally thinking people and the local societies. If we want to keep them we must find really new ways of deploying them.

Solar power is almost at the beginning. The installed capacity is 260,67 MW. This is strange enough for a country with very good solar radiation. You can find some PVs over the roofs of houses. But there aren’t serious solar power production facilities. In the case of solar we do not face the problems of wind, like the big land footprint, or the heavy landscape spoiling. And this can be avoided in the future if we do not use important land for the installation of solar PVs. The solar power’s land footprint is one of the lowest. Around 1%. We can use deserted industrial areas and open pits (e.g. coal and other minerals mines, or for marble and stones used in building industry etc.). Following this solution solar power can give the necessary electricity for decreasing the fossil fuels production. With 1% land coverage solar power is able to cover the primary electric energy production of the country. This is less from the almost 1,5-2% of land used for wind farms (already in use but offering only around 3% of the total electric energy production. The price per MWh is almost 3 times bigger than the price from thermal units. This must change. Otherwise the cost of mitigation will stay to expensive for the shift from CO2 correlated energy to clear energy. It is not logical to buy 4 times more expensive solar power in Greece than in Germany. The medium price in 2016 is 257€/MWh.

Bio-fuels is not a great idea for this situation. Although there are good results from some research centers (polytechnic and university schools) generally they are expensive and their CO2 emissions are not minimal.

One of the important parts of the solution is the improvement in efficiency and efficacy of energy technologies. New lightening technologies, better thermal insulation of houses and big buildings, more public transportation, better and newer cars, bicycles and more walking (also a health exercise on the same moment) must be part of the energy use and the energy planning for the near future. One of the advantages of these solutions is that they are not very expensive. Some of them have no cost, because they are just different ways of living and thinking. And all of them can be applied very fast in short time periods (days, months or just some years). All of these result to Carbon Reduction. Some examples: Driving your car 50% less or carpooling with another person can save ~1000-3000 kg CO2e/yr. Upgrading the lightning technology of a medium sized house can save ~100-300 kg CO2e/yr.

Other methods.

More taxes in not going to have good results. The country faces 30% GDP decline and 50% increase in taxes and consumer values. Nobody can pay –or can accept to pay- more money for CO2 reduction.

Hydroelectric is already an important factor. But it is difficult to accept the idea of a big increase of its part to the total energy production. The main reason is the fact that there is less water in the country and because of climate change we can not expect a better future situation. Fewer rains and snows, more heat and perspiration makes the water for hydroelectric a valuable asset that is going to be less and as a result you can’t expect to find a CO2 solution to this kind of energy production. Another well known problem is the big land use and landscape alterations that are caused by huge dams etc. The idea of small hydroelectric for islands etc isn’t a serious one. The water problem is more serious there and even under the best perspectives the planning is about 0,5% participation at the final energy sum. These kind of ideas are mainly for political reasons and not for energy reasons. They are for the impression not for the result.

But the CO2 reduction (and of the other GHG) needs a really new process, a radical change of the basis of energy production for the country.
Taking into account the previous the only really logical solutions, with the best results and prospects, are solar power under a reasonable cost and land use and improvement in efficiency and efficacy.

[Synthesis Assignment: Policy Recommendations, Aug. 2016, written by Dimitrios D.Soufleris –  HarvardX: ENGSCI137x Energy Within Environmental Constraints]

Written by dds2

Νοέμβριος 21, 2016 at 1:12 πμ

Watch 30 Years of Rainforest Vanish in 30 Seconds

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Drawing on millions of images taken by eight NASA Landsat satellites, Google has created a “global, zoomable time lapse of Earth’s surface” that show us the changes — shocking and scary — that have occurred around the world as a result of global warming and urbanization.

In the Landsat programsurveillance spacecraft were put to use not for investigating what’s going on in outer space, but to keep track of what is happening to the Earth. NASA launched the first Landsat satellite in 1972 specifically  for “public monitoring of how the human species was altering the surface of the planet.”

In 2008, the U.S. government ruled that the Landsat pictures should be available for free; one had previously had to pay to access them. Google contacted the U.S. Geological Service about using the images and also sought to gain access to even more photos (in the form of traditional prints and negatives) from Landsat ground stations around the world. It took six months to digitize everything and more to reprocess them.

You can now see the results via Google Earth Engine. As Time magazine comments, the pictures

…tell the pretty and not-so-pretty story of a finite planet and how its residents are treating it — razing even as we build, destroying even as we preserve. It takes a certain amount of courage to look at the videos, but once you start, it’s impossible to look away.

The Timelapse image of the rain forest in the state of Rondonia in western Brazil shows not only how an area the size of West Virginia (nearly 25,000 sq. miles) has disappeared from 1978 to 2003, but also the “fishbone pattern” in which deforestation occurs: loggers first make a path in the forest. This thickens and grows and then more paths are built and more, and more, and more.

For a too-clear illustration of how global warming has caused rapid change with long-term effects, you  need look at only the image of the retreat of the Columbia Glacier in Alaska from 1984 – 2012. Since it was first observed in 1794, the glacier’s extent remained unchanged until the latter half of the 20th century, as you can see.  At one point in 2001, the glacier was shrinking at an estimated speed of 98 ft. (30 meters) per day. In just a few decades (within the lifetime of many of us), the glacier has lost about 12 miles of its length and nearly 1,300 feet of its thickness.

The Google images also show how urbanization is rapidly changing the world around us. More people than ever in human history now live in cities, having left villages and farming for cramped housing in urban centers in the hope of better job prospects. Just one example is Las Vegas, which has grown from a population of 500,000 in 1980 to about 2 million now. From 2000 to 2o1o, its population grew by nearly 50 percent, making it probably the only urban area outside of the developing world with such accelerated growth.

The advance of Las Vegas’ sprawl into the desert — all those people need someplace to live and then roads and infrastructure to transport them to jobs — is quite apparent in the Timelapse image. The region receives almost no rain fall and depends on Lake Mead for most its water supply, but this is lessening in part because of the prolonged drought and also due to the demands of Las Vegas’ many residents.

Another city whose phenomenal growth has come with massive alterations to the environment is Dubai. Once a city of about 300,000 with an economy based on pearl diving, Dubai has become a major metropolis and the Mideast’s financial center with the world’s tallest skyscraper, the largest mall, biggest theme park and the longest indoor ski run. Its population is currently  2.1 million and growing. Islands (two in the form of palm trees) have been created and, as in Las Vegas, expansion continues into the desert.

Just as there is a “red list” for endangered species, scientists are developing one for ecosystems and it is high time indeed. The massive loss of rain forests, the shrinking of glaciers and the advance of cities in the desert as revealed via the Google Earth Engine show too clearly why too many ecosystems around the globe are deeply endangered.

Read more: http://www.care2.com/causes/watch-30-years-rain-forest-vanish-in-30-seconds.html#ixzz2UyGub1dR

Η βρώμικη ενέργεια (κατά την Greenpeace)

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Η Greenpeace είναι πάντοτε υπερβολική και μονοδιάστατη. Στην δουλειά της που δημοσιεύται πιο κάτω βρίσκεται η μία (πολύ σημαντική βεβαίως) πλευρά του νομίσματος. Πάρα ταύτα, το δημοσιεύω, γιατί συνολικά έχει σημαντικότατες πληροφορίες. Και για να θεμελιώσω, λίγο μόνο, τις ενστάσεις μου, λέω πως αρκεί λίγο μόνο γαϊδουράγκαθο να χρησιμοποιούσε η ΔΕΗ και όλα θα γίνονταν καλύτερα…


Written by dds2

Φεβρουαρίου 1, 2013 at 5:23 μμ