http://theenergycollective.com/willem-post/169521/wind-turbine-energy-capacity-less-estimated (Η εικόνα μεγαλώνει με κλικ, και έχω αντιγράψει αυτούσιο το άρθρο, στο τέλος)
Αναφέρεται στις ΗΠΑ όπου το "20%" από αιολικά, εάν εφαρμοστεί, θα κοστίσει τρισεκατομμύρια. Αλλά τηρουμένων των αναλογιών...
1. Οι συντελεστές φορτίου ή διαθεσιμότητας (capacity factor) είναι μικρότεροι από ότι διαφημίζουν οι αιολικοί, με αποτέλεσμα το κόστος να είναι μεγαλύτερο.
2. Πρόσφατες μελέτες από την Δανία και την Αγγλία δείχνουν ωφέλιμη ζωή 15-20 χρόνια αντί των 25 που επικαλούνται οι αιολικοί για να χρηματοδοτηθούνε. Αυτό συνεπάγεται μεγαλύτερες ανάγκες αντικατάστασης και αυξημένες ανάγκες κεφαλαίων.
3. Οι αυξημένες ανάγκες κεφαλαίων με τις χαμηλότερες διαθεσιμότητες (ή συντελεστές φορτίου) θα αυξήσουν το σταθμισμένο κόστος της ενέργειας.
4. Εφ' όσον άλλες χώρες δεν ακολουθούν τους περιορισμούς της Ντόχα (COP-18 2012) όσοι βάζουν αιολικά επιβάλλουν στον εαυτό τους συγκριτικό μειονέκτημα.
5. Τα αιολικά είναι εντελώς αναποτελεσματικά στην μείωση CO2 σε σχέση πχ με την αύξηση στην ενεργειακή αποτελεσματικότητα, και αναρωτιέται κανείς εάν ο Δυτικός κόσμος είναι στον σωστό δρόμο στο θέμα αυτό.
6. Οι Ρυθμιστικές Αρχές δεν ρώτησαν είτε από έλλειψη δέουσας επιμέλειας, είτε από άγνοια ηλεκτροπαραγωγής, πληροφορούνται μόνο από αιολικούς κυνηγούς επιδοτήσεων και αιολικούς πλασιέ, και προσκυνάνε φιλο-αιολικούς πολιτικούς, και ευνoούν τα αιολικά. (Λαμόγια ή αχυρανθρώπους τους λέει, αλλά ...ευγενικά)
7. Η επιλογή της αιολικής ενέργειας προωθείται από επιδοτήσεις και πολιτικούς που θέλουν να εμφανιστούν ότι κάνουν κάτι για την παγκόσμια θέρμανση (ποια παγκόσμια θέρμανση), η διαδικασίες είναι πια τρωτές και δημιουργούν δυσπιστία, ενόχληση, άγχος και διχασμό στο κοινό.
Η ιστοσελίδα αυτή δεν είναι της Siemens, αλλά είναι sponsored by Siemems. Ενώ αυτή η εταιρία μας έπρηζε με αιολικές διαφημίσεις μέχρι πριν 2-3 χρόνια, από το 2011 έχει μάλλον στραφεί σαφώς κατά των ΑΠΕ για ηλεκτροδότηση.
20/12/ 12 Κάποιος (Γερμανικός) φούρνος θα γκρεμίσει
17/3/12 Η μεταστροφή σε ΑΠΕ δεν πετυχαίνει ούτε στην Γερμανία
18/1/12 Η Siemens για το κόστος των ΑΠΕ
9/1/12 Πόσο αποτελεσματικά είναι τα αιολικά στην Γερμανία;
6/4/11 Μέσα στην Πράσινη Παγίδα
27/3/11 Κοινή (Γερμανική) λογική
17/3/11 Νεκρικό ποίημα για το τσουνάμι
5/3/11 Μάθημα αιολικών (1) Ε.ΟΝ, από το 2005!
Energy From Wind Turbines Actually Less Than Estimated?
Posted January 10, 2013
The US-DOE is envisioning the US having at least 20% of its energy from IWTs by 2050. Most of these would be located in the Great Plains, where are the good to excellent winds.
The National Renewable Energy Laboratories, NRELs, have proposed High Voltage Direct Current, HVDC, lines from the Great Plains to the East Coast, where the people are. Those lines have much less line losses than HVAC lines, and can be buried, or on pylons, as needed, to satisfy NIMBY concerns.
The implementation of at least 20% wind energy will have major impacts on the US electric power system and will require trillions of dollars.
However, it appears the capacity factors of wind energy projects are much less than estimated by project developers. As a result, the capital costs and environmental impacts of implementation would be much greater, because a greater capacity of wind turbines and transmission systems would be required to generate the same quantity of energy.
Recent studies of IWT useful service lives in Denmark and the UK indicate these lives are about 15 - 20 years, say 17 years, instead of the 25 years typically used by IWT project developers to obtain bank financing, federal and state subsidies and "Certificate of Public Good" approvals. Instead of 2 replacements in 2 x 25 = 50 years, there will be 3 replacements in 3 x 17 = 51 years, i.e. a 50% greater replacement rate.
As the above US IWT build-out proceeds, almost all of the existing 52,000 MW of IWTs will need to be replaced during 2012 - 2029, plus the new IWTs built during 2012 - 2029 will need to be replaced during 2029 - 2046, etc.
The increased capital cost of IWT build-outs and replacements and the impact of the lesser CFs will greatly add to the US levelized cost of energy.
Unless other developed and developing nations handicap themselves in the same manner (which appears increasingly less likely, based on COP-18 in Dohu, Qatar, in 2012), the US will be at an even greater economic disadvantage than at present.
Add to that situation wind energy not being anywhere nearly as effective regarding CO2 emission reduction as increased energy efficiency, one may wonder if the western world is on the right course regarding CO2 emission reduction.
Germany's Renewable Energy: Germany has set the ambitious goals of increasing renewable energy to 35 percent of total power consumption by 2020 and 80 percent by 2050 while phasing out all of Germany's nuclear power plants by 2022.
Germany, after it closed about 50% of its nuclear plant capacity, is rapidly building out renewable energy facilities. At the end of 2012, it had about 31,000 MW of IWTs producing about 8% of its total generation and 32,800 MW of PV solar systems producing about 4.8% of its total generation.
Transmission systems and balancing plant capacity to support these rapid build-outs were not built in time to prevent frequent grid instabilities that adversely affect industrial production.
As a result of the existing RE build-outs, Germany has the 2nd highest household electric rates in Europe, about 28 eurocent/kWh, including taxes, fees, surcharges, etc; Denmark has the highest at about 31.5 eurocent/kWh; France has the lowest.
Germany's Wind Energy: Energy transmission facilities between North Germany and South Germany were not that important before the IWT build-out in North Germany and the PV solar system build-out in South Germany. As a result of these build-outs, there frequently is excess wind energy in the North and excess solar energy in the South.
Germany is planning to build HVDC lines from North Germany to South Germany. Because of NIMBY concerns, these lines are about 10 years overdue.
Germany has exported its variable wind energy to Poland, but Poland does not want it, because it upsets the grid, which is largely coal-based. Poland is building a big switch at the border to stop Germany's variable energy exports.
Germany also exports a small quantity of its variable energy at very low prices to the Netherlands. Fortunately, the Netherlands has a large capacity of CCGTs and OCGTs for balancing it.
Germany already practices curtailment of wind energy production, but IWT owners, a politically well-connected group, have complained about losing revenues, and CCGT plant owners have complained about their reduced outputs, inefficiently produced, adversely affecting their plants' economic viability.
Germany's Solar Energy: About 22,000 MW of Germany’s 32,800 MW of PV solar systems (end 2012) are in South Germany. On a sunny summer day, from about 0 MW at 6 AM, the PV solar output increases to about 16,000 MW at noon, and back down to about 0 MW at 6 PM. This creates major disturbances on the grid and, as PV solar panels cannot be turned off, Germany has to export the energy as much as possible.
Germany has been exporting the excess energy to France and the Czech Republic at very low prices, after subsidizing it at 30 - 60 eurocent/kWh. France has a significant hydro capacity for balancing part of the excess energy, but the Czech Republic is building a big switch. Any excess energy not wanted gets grounded!!!
California's Wind and Solar Energy: Sometimes California wind speeds suddenly decrease to near zero, or a cloud bank passes over solar arrays in the desert. The result is a rapid decrease in wind or solar energy that could cause instabilities and blackouts in the grid.
To prevent such instabilities and blackouts, OCGTs are kept in spinning mode, i.e., consuming energy (equivalent to about 5 to 7 percent of the energy consumption at rated output), but not sending power to the grid, to instantly make up for the missing energy, and other generators, such as CCGTs, are started and stopped, as demand requires it.
Maine Ridge Line Wind Energy: Maine plans to have 2,000 MW of IWTs by 2015 and 3,000 MW by 2020. About 400 MW were in operation at the end of 2012.
All US IWT owners connected to the grid have to report their quarterly outputs, MWh, to the Federal Energy Regulatory Commission, FERC. The data is posted on the FERC website, and, with some effort, can be deciphered.
Below are some numbers regarding the much less than expected results of the Maine ridge line IWTs for the past 12 months.
Mars Hill, 42 MW, CF = 0.353; uniquely favorable winds due to topography.
Stetson I, 57 MW, CF = 0.254
Stetson II, 26 MW, CF = 0.227
Kibby Mtn 132 MW, CF = 0.238
Rollins, 60 MW, CF = 0.238
Record Hill, 50.5 MW, CF = 0.197
The Maine weighted average CF = (42 x 0.353 + 57 x 0.254 + 26 x 0.227 + 132 x 0.238 + 60 x 0.238 + 50.5 x 0.197)/(42 + 57 + 26 + 132 + 60 + 50.5) = 0.247
Note: CF reduction due to aging is not yet a major factor, as all these IWTs were installed in the past 5 years.
Remember, the developers told Maine regulators their IWT projects would have CFs of 0.32 or greater, to more easily obtain bank financing, federal and state subsidies and "Certificate of Public Good" approvals. The lesser ACTUAL CFs are likely due to:
- Winds entering 373-ft diameter rotors varying in speed AND direction under all conditions; less so offshore, more so, if arriving from irregular upstream terrain.
- Turbine performance curves being based on idealized conditions, i.e., uniform wind vectors perpendicularly entering rotors; those curves are poor predictors of ACTUAL CFs.
- Wind testing towers using anemometers about 8 inch in diameter; an inadequate way to predict what a 373-ft diameter rotor might do.
- CFs declining due to aging IWTs having increased maintenance outages.
The net effect of all factors shows up as ACTUAL CFs being much less than estimated by IWT project developers.
- did not ask the right questions on their own (likely due to a lack of due diligence and power systems knowledge), or
- ignored/brushed aside the engineering professionals, who gave them testimony or advised them what to ask, or
- received invalid/deceptive answers from subsidy-chasing IWT project developers and promoters, or
- kowtowed to wind energy-favoring politicians allied with wind energy oligarchs, i.e., not hinder IWT build-outs.
Because of subsidy-chasing by IWT project developers, and politicians wanting to be seen as doing something about climate change and global warming, the vetting process of proposed IWT projects by boards of political appointees is much compromised, which is creating distrust, resentment, anxiety and division among the lay public.
Worldwide Wind Energy: Below are the averaged CFs in some widely-dispersed geographical areas for the 2006 - 2011 period.
Germany, onshore, CF = 0.187
Denmark, including offshore, CF = 0.251; a high value due to greater offshore CFs.
The Netherlands, CF = 0.228
The US, CF = 0.289; a high value due to excellent winds in the Great Plains.
Texas, CF = 0.225
Ireland, CF = 0.283; Ireland and Scotland have the best winds in Europe.
New York State, CF = 0.249
Vermont Ridge Line Wind Energy: It should be obvious to the VT-Public Service Board and other government entities, whereas IWT project developers make claims of IWTs having:
- CFs of 0.32 or greater, this claim should be discounted to at most 0.25, based on ACTUAL RIDGE LINE PRODUCTION RESULTS.
- Useful service lives of 25 years, this claim should be discounted to at most 17 years, based on ACTUAL USEFUL SERVICE LIFE RESULTS.
The spreadsheet levelized energy cost analyses prepared by IWT project developers, currently based on their claims, should be revised to better reflect the real world, rather than an "Alice in Wonderland" world.
Failure to do this is malfeasance of a public trust, which has legal consequences. See related post on wind turbines in Vermont.