glOBal Wind energy OuTlOOk 2010 - Global Wind Energy Council

T h e G l O B a l W i n d E n e r g y O u t l O O k S c e n a r i O S
Production and share of global electricity supply
Assumptions on turbine capacity…
Individual wind turbines have been steadily growing in terms
of their nameplate capacity – the maximum electricity
output they achieve when operating at full power. While the
average size of turbines still differs dramatically from country
to country, there has been a market trend towards bigger
turbines across all markets. For the purposes of the GWEO
scenarios, this trend is expected to continue over the next
few decades.
Dhule wind farm, India
© Suzlon
ing to this projection would stand at 415 GW in 2020 and
572 GW in 2030. For this to happen, annual additions would
need to decline substantially, especially in China, although
there is no indication of this happening at present. Overall,
the Reference scenario seems disconnected from current
developments, and curiously pessimistic.
While the Reference scenario suggests that between 20 and
26 GW of new capacity will be added each year between
2010 and 2020, reaching 41 GW/year only in 2030, the
Moderate scenario envisages the addition of 40.2 GW two
decades earlier (in 2010), followed by 63 GW/year by 2015,
close to 90 GW/year by 2020, and almost 150 GW/year by
2030. This translates into 100 GW more installations per year
than the Reference scenario by 2030, even though the annual
market growth rate would by then have dropped off to a
modest 4% per year. In terms of total installed wind power
capacity, 830 GW would be reached in 2020 (twice as much
as under the Reference scenario), and close to 1,800 GW by
2030 (more than three times as much).
In the Advanced scenario, the difference would be even
more striking. Annual market growth rates here start at 27%
for 2010, and then decrease to 17% by 2015, 9% by 2020
and finally 5% by 2030 – compared to an average cumulative
market growth of 28% per year over the past decade. These
growth rates would translate into annual markets of 120 GW
by 2020, increasing and stabilising at around 185 GW by
2030. These projections would result in a total installed
capacity of just over 1,000 GW by 2020 and 2,300 GW by
2030.
It is also assumed that each turbine will have an operational
lifetime of 20 years, after which it will need to be replaced.
This ‘repowering’ or replacement of older turbines has been
taken into account in the scenarios.
… and capacity facTOrs
A wind turbine’s ‘capacity factor’ refers to the percentage of
the nameplate capacity that a turbine installed in a particular
location will deliver over the course of a year. This is primarily
an assessment of the wind resource at a given site, but capacity
factors are also affected by the efficiency of the turbine
and its suitability for the particular location. For example, a
1 MW turbine operating at a 25% capacity factor will deliver
2,190 MWh of electricity in one year.
From an estimated average capacity factor today of 25%, the
scenario assumes that improvements in both wind turbine
technology and the siting of wind farms will result in a steady
increase. Capacity factors are also much higher at sea, where
winds are stronger and more constant. The growing size of
the offshore wind market, especially in Europe, will therefore
contribute to an increase in the average. As a result, across all
three scenarios, we assume that the average global capacity
factor will increase to 28% by 2015 and then 30% by 2036.
Although capacity factors will vary from region to region, we
have assumed these same global averages for the regional
scenarios as outlined below.
Projections FOr electricity
demand developmenTS
While it is of interest to calculate how much power would
actually be generated by wind energy in the three scenarios,
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