...
Post by Raffaele Castagno"The substitution of oil for nuclear power in the electricity sector was
very successful and brought the electricity sector share in oil consumption
down to 1.5% by 1985."
ROTFL...,
e intanto il consumo di fonti fossili complessivo aumenta.
Intanto te (e quell'altro del carico di base) provate a spiegare come mai
il fattore di efficienza con cui viene prodotta energia elettrica dai 58
reattori francesi è appenna del 76%, ovvero potrebbero e dovrebbero
produrre 552 TWh annui e si limitano a 421 di cui un'ottantina circa la
vendono agli stati circnvicini (altrimenti diovrebbero buttarla nel cesso).
E poi un altro paio di punti del rapporto di Schneider che spiegano bene
la convenienza dell'energia elettrica nucleare francese:
1) A critical analysis of the impact of French electricity exports was
carried out by independent think
tank INESTENE in 200240. The report estimates that the power exports,
analyzed over the years 1995
to 2001, were a major loss maker. According to INESTENE, the official
revenues from exports did not
cover the official nuclear generating costs. In addition, detailed
modelling reveals that nuclear power
covered less than three quarters of the electricity that was exported, one
quarter being covered by coal
fired power plants and around 3% by fuel oil, at much higher cost. In
addition, INESTENE has made
its own cost assessment factoring in the costs of electricity transport,
the specific costs of the share of
fossil fuel power, specific costs of nuclear power (research, fuel,
investment, dismantling, insurance,
external costs). According to the INESTENE calculations annual losses vary
between a minimum of
800 million and a maximum 6 billion.
2) Such a load curve is highly uneconomic, because it requires a
significant generating capacity for very
short operational periods or the importation of peak load power at very
high cost. Between 2005 and
2007 France imported an average of close to 30 TWh per year, of which 17.5
TWh from Germany
alone41. The exact costs of the power imports are not public. However,
short-term peak load deliveries
can be many times more expensive than base load exports in the framework
of multi-annual
agreements.
The peak load problem became so urgent that in 2006 EDF decided to restart
2,600 MW of
mothballed oil fired power plants, the oldest of which had started up in
1968 and added them to the
thermal power plant fleet that had started up between 1950 and 1984. The
new-old oil capacity can be
compared to that of the new nuclear project at Flamanville with 1,600 MW
under construction since
December 2007. Over the past few years France has already generated twice
as much electricity from
oil-fired power plants as the UK and the situation is likely to become
worse. At the same time,
independent power producers have gained ground in France. The company
POWEO alone aims at
3,400 MW of installed capacity by 2012 of which 600 MW of renewable
energy.42 The rest of
POWEOs new capacity will be essentially natural gas peak load plants. The
company calculated that
the investment was worthwhile based on an operating time of 100 hours per
year43.
Electric space heating is not only uneconomic it is also an energetic
absurdity and highly polluting.
Instead of using primary energy directly (natural gas, oil, biomass
),
mainly fossil fuels, including
coal in foreign countries, are burnt in power plants. Around three
quarters of the energy is lost in the
form of waste heat and distribution losses before the electricity is
re-transformed into heat in people's
homes (see figure 12). An assessment published by Gaz de France in 2007
puts the nuclear share of
each additional kWh consumed by electric space heating as low as 10%. The
high ratio of fossil fuels
in the mix would lead to specific emissions of over 600 g of CO2 per kWh,
more than ten times the
official average emission per kWh. Even the French Secretary of State for
Ecology, Nathalie
Kosciusko-Morizet calls the development of electric space heating an
"error". She considers it "a
French folly" to transform electricity into heat, and "even an aberration
from a thermo-dynamic point
of view".44
In pratica con 58 reattori nucleari, comprano energia nei momento di
picco, quando è più cara, e per metterci una toppa, sono costretti a
riesumare vecchi cassoni di centrali del 1968 a Olio Combustibile,
ROTFL...
Aleph
--
questo articolo e` stato inviato via web dal servizio gratuito
http://www.newsland.it/news segnala gli abusi ad ***@newsland.it