Wind energy efficiency

Document Sample
Wind energy efficiency Powered By Docstoc
					Wind energy efficiency
An excerpt from the
2005 German wind energy report

Compiled by the Institute for Solar Energy Supply Systems (Institut für Solare Energieversorgungstechnik, ISET),
on behalf of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety.
Reworked and amended special reprint by the German Wind Energy Association (Bundesverband WindEnergie e.V.), Berlin 2006

Institut für Solare Energieversorgungstechnik (ISET)    Bundesverband WindEnergie e.V. (BWE)
Verein an der Universität Kassel e.V.                   Berlin office
Königstor 59                                            Marienstraße 19 – 20
34119 Kassel, Germany                                   10117 Berlin, Germany                        
Tel.: +49(0)561/72 94 -0                                Tel.: +49(0)30/2 84 82 -121
Fax: +49(0)561/72 94 -100                               Fax: +49(0)30/2 84 82 -107

                                                                                                                        EU Commission: The support
                                                                                                                   of electricity from renew-
                                                                                                                   able energy sources. Brussels,
                                                                                                                   7.12.2005, COM (2005) 627.

Wind energy on the route to competitiveness                                                                        2)
                                                                                                                        Cf. DEWI Magazine, 27/2005,
Wind energy technology has taken considerable strides   tions made by the German Wind Energy Institute             pp. 44 onwards; Staiß, Frithjof:
forward in Germany over the last 20 years. Positive     (DEWI), over 50% of the world’s wind turbines and          Die Erneuerbaren Energien in
basic conditions such as research, development and      their components are made in Germany. The export of        Zahlen – 2005 und Ausblick.
promotional measures and the competitive financing       wind power technology accounts for about 60% of the        (Renewable energies in figures
options helped advance technological development in     approximately 5 billion euros of German manufacturers’     – 2005 and future prospects.)
the 1990s. Setting a minimum price system for wind      sizeable overall turnover, thus securing the majority of   Stuttgart 2006; http://www.
power payments combined with the Electricity Feed Act   the sector’s approximately 64,000 jobs.2)        
(1991-2000) and Renewable Energy Sources Act (from      At the same time, prices for wind turbines and wind        halt/36645/20012/
April 2000) provided for planning reliability and the   power generation have come down markedly due to
effective and efficient expansion of wind power.1)       increased manufacture quantity, optimised production       3)
                                                                                                                        Cf. German Federal Ministry
By 2005, wind power already accounted for 5% of gross   methods and more efficient system technology. Produc-       for the Environment (Ed.):
electricity consumption. Whereas installed capacity     tion costs for wind-generated power are already compa-     Ausbau Erneuerbarer Energien
in 2000 amounted to approximately 7000 megawatts,       rable to those of new, conventional power stations.        im Stromsektor bis zum Jahr
by the end of 2005 the figure was closer to 18,500       The German Federal Ministry for the Environment            2020. Vergütungszahlungen
megawatts. Rapid technological development brought      considers that, by 2015 at the latest, wind power will     und Differenzkosten durch das
German manufacturers and suppliers a leading role in    be cheaper on the power exchange than conventionally       Erneuerbare-Energien-Gesetz.
the world wind turbine market. According to calcula-    produced electricity.3)                                    (Expansion of renewable ener-
                                                                                                                   gies in the electricity sector to
                                                                                                                   2020. Payment and differential
                                                                                                                   costs as per the Renewable
                                                                                                                   Energy Sources Act.)
                                           Wind turbines are becoming ever more affordable
         Prices adjusted for inflation,     Whereas the price for a kilowatt of installed capac-                 power station has a nominal capacity of approximately
    standardised at 1995 price             ity per system stood at 1260 euros in 1990, by 2004                  1000 megawatts.
    level, including delivery and          the system price had fallen to 890 euros per kilowatt,               The larger a system is, the more expensive it is to
    installation.                          representing a reduction of 29%.4) To this effect, a                 purchase. However, wind turbines with a greater hub
                                           one-megawatt wind turbine, i.e. with a capacity of                   height and large rotor diameter are more economical
         Here the annual yield is equal    1000 kilowatts, would cost 890,000 euros. Further-                   to run. This means that a kilowatt hour of electricity
    to the reference site yield in         more, the technology used in newer systems is more                   is produced more cheaply the larger the wind turbine
    accordance with the Renewable          sophisticated and the turbines and rotor blades work                 and the better its technology is. If you compare the
    Energy Sources Act. The refer-         with greater efficiency. In 1990, only small systems                  annual costs of power yield for 1990 and 2004, the
    ence site registered an average        with a total capacity of 60 megawatts were functional                price of a kilowatt hour has reduced by 53% from 80 to
    annual wind speed of 5.5m/s            in Germany. In contrast, by the end of 2005, 18,500                  38 cent/Euro.5)
    at a height of 30 metres.              megawatts of capacity had been installed and the                     Therefore, the price of wind turbines decreased by 29%
    A 1.5-megawatt system at the           largest wind turbines had a nominal capacity of up to                between 1990 and 2004 while the price of a kilowatt
    reference site produces ap-            six megawatts. For comparison: a nuclear or brown coal               hour of wind power decreased by as much as 53%.
    proximately 4,500,000 kilowatt
    hours per year at a tower height
    of 100 metres, enough for 2000
                                           Fig. 1: Wind power learning curve, wind turbine price per kWh, annual energy yield (reference site)

                                                            1,00 €


                                                            0,10 €
                                                                 10                     100                  1.000               10.000               100.000
                                                                     Total installed nominal capacity (MW)

                                           Ever decreasing feed-in compensation for wind power
                                           Since 1991, electricity produced from wind power has                 The Bundestag amended it again on August 1st 2004
                                           been charged at a nationally fixed minimum price.                     with the “Act Revising the Legislation on Renewable
                                           In April 2000, the Electricity Feed Act, which had been              Energy Sources in the Electricity Sector” (see box on
                                           in force since 1991, was replaced by the Renewable                   right).
                                           Energy Sources Act (EEG).                                            Figure 2 shows the real decrease in feed-in compensa-
                                                                                                                tion since 1991 of approximately 23%. Calculations
2                                                                                                               based on figures for 2000.
Besides the Electricity Feed Act payments, which             often possible to combine subsidy schemes at the           6)
                                                                                                                             At 2004 prices. Cf. Rehfeldt,
changed annually, the federal government also                national and state level. The total cost of a kilowatt     Knud: Concise reports within
granted annual running cost subsidies to select              hour of wind power in 1991 thus stood at a maximum         the framework of the amend-
projects within the framework of its “250MW of Wind”         of 18.31 cent/Euro. Taking an average cost at today’s      ment to the Renewable Energy
programme. The states also granted investment cost           prices of 7.44 cent/Euro/kWh, this represents a drop       Sources Act/Wind Power Sec-
subsidies. This meant that in the early 1990s it was         in the minimum price of over 59% to 20066).                tion. Varel 2003. p.8.

Fig. 2: Feed-in compensation development for electricity produced from wind power




                                                                                                             Real compensation as per the Electricity Feed Act
              8,00                                                                                           Average real compensation over 20 years as per
                                                                                                             the Renewable Energy Sources Act

 ct. / kWh


                 1990             1995                  2000                 2005                  2010

                                                                                                                             Cf. also Zentrum für Energie-
     The generation of wind power is charged at a fixed price over 20 years
                                                                                                                        forschung ZES (Centre for En-
     in accordance with the Renewable Energy Sources Act (EEG).
                                                                                                                        ergy Research) Stuttgart (Ed.):
     An initial rate of 8.36 cent/Euro/kWh has been set for a minimum of five years for wind turbines which come
                                                                                                                        Electricity from renewable
     into operation in 2006. Subsequently, dependent on site quality, the feed-in compensation will be reduced
                                                                                                                        energies. Stuttgart 2003. pp.15
     to 5.28 cent/Euro/kWh. This reduction will come into effect at sites with very high yields at the end of the
                                                                                                                        onwards. Production costs for
     fifth operating year whilst the higher price will remain in force at other sites. This means that over the
                                                                                                                        a 1,300-kilowatt system in a
     20 years, dependent on site quality, there will be an average feed-in compensation of between 6.05 and
                                                                                                                        good coastal location can be as
     8.36 cent/Euro/kWh. The minimum tariffs decrease, in accordance with the Renewable Energy Sources Act,
                                                                                                                        little as 4 cent/Euro/kWh, are
     by a nominal 2% annually for newly operational systems. Thereby a system which becomes operational in
                                                                                                                        on average 6 cent/Euro/kWh
     2007 will have an initial rate of 8.19 cent/Euro/kWh and a basic rate of 5.17 cent/Euro/kWh. The Renewable
                                                                                                                        and at most 8 cent/Euro/kWh.
     Energy Sources Act foresees special regulations for repowering systems and offshore wind power. There is
     no obligation to pay remuneration for wind power systems which do not achieve at least 60% of the refer-
                                                                                                                             Calculation basis: specific
     ence yield at the planned site.
                                                                                                                        ex-works wind turbine costs
                                                                                                                        900 euro/kW, additional
                                                                                                                        investment costs 30% (curve

Wind power has the lowest electricity production costs                                                                  2: 20%), running costs 4.5%
                                                                                                                        (3.0%), imputed interest
                                                                                                                        7.5% (5.5%), financing period
Electricity production costs cover the total costs of        Curve 1 in figure 3 displays the electricity production
                                                                                                                        corresponding to amortisation
electricity generation by a new power station over           costs of commercially available 1.5- to 2-megawatt
                                                                                                                        period 16 years, service life
a given time period, i.e. investment, raw material,          wind turbines over 20 years; curve 2 displays a ver-
                                                                                                                        20 years, power yield from 60%
service costs and at least part of the external costs.       sion with somewhat lower estimates with regard to
                                                                                                                        to 160% of the reference yield.
The electricity production costs of a wind turbine with      additional investment charges and financial services.
a capacity of 2000 kilowatts over 20 years come to           The better the site, the lower the electricity produc-
6.4 cent/Euro/kWh for an average site. On the coast,         tion costs will be. However, even sites with poorer
where the wind conditions are best, they can even be         wind conditions, under 100% of the reference yield,
as low as 4.5 cent/Euro/kWh7).                               can compete with the costs of conventional electricity
                                                                Fig. 3: Production costs for electricity from wind power compared

                                                                                                                                                                             Natural gas (CCGT)
                                                                                                                                                                             Nuclear power
                                                                0,09                                                                                                         Black coal
                                                                0,08                                                                                                         Brown coal

                                        Specific costs (€/kWh)

                                                                                                                       ge pro
                                                                0,06                                                                n costs,
                                                                                                              Avera                           standar
                                                                                                                   ge pr                               d investm
                                                                                                                        oduct                                   ent, 20 yea
                                                                                                                              ion co                                        r runtime
                                                                0,05                                                                sts, low
                                                                                                                                             -pr iced
                                                                                                                                                               nt, 20 year
                                                                0,04                                                                                                       runtime

                                                                   60                     80                  100                  120                  140                                       160
                                                                                                       Renewable Energy Sources Act reference yield (%)

         Cf. RWI (Ed.). Electricity                             Wind power is already a low-priced energy source in                                                      Base load
    production costs for new                                    comparison. These are the average electricity produc-        Brown coal                                   8 cent/Euro/kWh
    conventional power stations                                 tion costs of conventional power stations over an            Black coal                                   9 cent/Euro/kWh
    yet to be built. RWI-Papiere, Nr.                           operating period of 20 years.9)                              Nuclear power                               10 cent/Euro/kWh
    47 (RWI papers, no. 47), 1997.                                                                                           Natural gas (CCGT)                          10 cent/Euro/kWh
    Going on the low raw material                                                                                            Source: RWI, 2005 prices
    prices of 2003, the Saarbrücken
    Institute for Future Energy Sys-
    tems (IZES) came up with the
    following average production
    costs over an operating period
    of 35 years: for black coal
                                                                Technological advances lower costs
    9 cent/Euro/kWh, brown coal
                                                                Energy yield and electricity production costs also de-       tion that can be expected from a reference site over 20
    8 cent/Euro/kWh and CCGT
                                                                pend on hub height and rotor diameter. The higher up         years as per the Renewable Energy Sources Act (approx-
    6 cent/Euro/kWh. Cf. IZES
                                                                you go, the more wind there is. And the bigger the ro-       imately 7.9 cent/Euro/kWh). A 2000-kilowatt system on
    (Ed.). Ausgewählte Fragestel-
                                                                tor is, the greater the quantity of the wind that will be    a 30-metre tower already gives energy production costs
    lungen zur EEG-Novellierung,
                                                                caught. With standard investment10), a 1000-kilowatt         of little more than 6.4 cent/Euro/kWh. Hence the latest
    (Selected questions on the
                                                                nominal capacity system with an annual energy yield of       technology can significantly reduce electricity produc-
    amendment to the Renewable
                                                                100% of the reference yield will have electricity produc-    tion costs both in newly-built wind parks or when old
    Energy Sources Act, Saar-
                                                                tion costs of approximately 6.9 cent/Euro/kWh.               systems are being replaced.
    brücken 2004, p.25.
                                                                This figure is lower than the average feed-in compensa-

                                                                Fig. 4: Comparison of electricity production costs for various system sizes


                                                                                               System 1: 1000kW, 70m hub height, €1100/kW
                                                                                                        System 2: 2000kW, 100m hub height, €1000/kW
                                        Specific costs (€/kWh)




                                                                   60                     80                  100                  120                  140                                       160
                                                                                                       Renewable Energy Sources Act reference yield (%)