The Emerging Electrical Markets for Copper



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Wind Farms: Wind towers connected to the grid are normally in groups. This allows the components used to connect each tower to the grid to be shared, thus reducing cost. Grouping of towers also has merit in greatly reducing the time and expense of gaining environmental permits, as where it is possible to site one tower it may be possible to site many of them.
Individual wind towers may or may not contain a transformer, stepping up electricity to medium voltage. Most modern ones do. Where there is a transformer, cables from the wind tower are routed to a central collection point, from which runs a single cable (often 35 kV) to the grid substation, where a transformer steps up the electric to grid transmission voltage. Where there is no transformer in the individual towers, there is a transformer serving a group of turbines at a central collection point.
A large wind farm may consist of a few dozen to several hundred individual wind turbines, and cover an extended area of hundreds of square kilometres. Most existing farms are onshore, although a high proportion of planned development is offshore.
Most existing onshore wind farms are collections of wind turbines with 0.69 MW or 1 MW capacity each, although higher rated units are now being installed. It is normal for each wind tower to have its own transformer with associated switchgear to raise voltage to 10-35 kV. Cables running from each tower are typically buried underground. Where there are no internal transformers in the wind towers, the onshore site will include one or more step up transformers to serve a group of turbines.
The electricity from the wind farm normally has to go through a substation for step up to grid transmission voltage (often 110 kV). Sometimes, it is possible to connect the wind far directly into the MV utility network in onshore systems.
Offshore wind farms are normally much larger, often with over 100 turbines with ratings up to 3 MW and above. The harsh environment means that the individual components need to be more rugged and corrosion protected than their onshore components. The offshore location means that a connection to shore via a subsea MV cable is necessary, sometimes of a considerable length.
Small Wind Turbines: Small scale wind turbines have become widely available over the past few years, in part stimulated by government grants. Systems vary in capacity from 100 watts to 6 kilowatts for private use, with larger turbines of up to 50 kilowatts being employed for community projects and by business. The smallest units of 600 watts may be used for charging batteries for caravans or boats, while the larger private systems are for use to supply all or most of the individual consumer’s electricity needs.
Two types of small scale wind turbines are available, mast mounted and roof mounted. Mast mounted systems are generally more cost effective, but less likely to achieve environmental approval. Most small wind turbines generate DC electricity, so require a DC/AC inverter for most applications.

      1. Market Forecasts by Sector

The wind power market consists of three elements:



Figure 54: Global Wind Power Capacity 1996-200910



Figure 55: Annual Installation of Wind Power Capacity 1996-200911



  1. New wind farms (onshore or offshore).

  2. “Repowering”, meaning the replacement of existing wind turbines with new and larger units. The older replaced types are appearing on the second hand market and will allow developing countries to start using wind power at lower costs.

  3. Small individual wind turbines.

The installation of new wind farms is by far the most important market, but a significant market in repowering is now beginning to emerge in Germany and Denmark, where there is a long-established installed base. Repowering is an attractive option as it sidesteps the need for new environmental approvals. It is set become a far more important part of the overall market in the next decade. Redundant units resulting from repowering are in some cases sold to developing world countries.


As can be seen in Figure 54, the amount of wind power capacity has increased exponentially, from a very small base of around 0.6 GW in 1996 to around 160 GW in 2009. Despite the growth, a few countries remain disproportionally large in the overall picture, these including Germany (16.3% share), Spain (12.1% share), and tiny Denmark (2.2% share).

Figure 56: Forecast Wind Generating Capacity in Place (GW)



Figure 57: Forecast Installation of Wind Generating Capacity (GW)

In Figure 55, showing annual installation of wind power capacity, we see that the market really began to take off in the mid-2000s. Market size more than trebled between 2005 and 2009. Germany and Spain continued to feature highly in installation in 2009, but the strongest markets were the United States and China, the latter having quickly become the world’s leading market from a very small base just a few years ago.


With ambitious targets for the share of renewable energy being set by government, the prospects for wind energy look good. In Europe, in March 2007 a binding agreement to increase the share of renewable in the total energy mix to 20% by 2020 was made. In January 2008 this was formalised in specific targets by sector and by country, divided between electricity, heat and cooling and transport. The target for electricity was set at 34%, in which wind would have to play a dominant role.
Our forecasts of wind energy installation are based on those provided by the European Wind Energy Association (EWEA) and the publication “Wind Energy – The Facts” published by a consortium led by the EWEA. The figures show a quadrupling of global capacity in place from 178 GW in 2010 to 711 GW in 2020. The forecasts are based on the more moderate of the EWEA scenarios, which also looks at a picture where wind energy will achieve a greater penetration given greater support by government.
The forecast show that Europe will continue to be a major contributor to this growth in capacity, with an annual growth rate of 10.8% p.a. Growth in capacity in other areas of the world, however, is expected to exceed that in Europe.
Such rapid growth in capacity in place will inevitably mean a high rate of installation. We forecast that total installation will treble between 2010 and 2020, from 24 GW to 78 GW per year. This installation includes some replacement, or “repowering”, a market that is forecast to grow in Europe from 0.1 GW in 2010 to 4.2 GW in 2020. All of this repowering will be onshore, offshore repowering only becoming a significant feature of the market after 2020.
The location of new wind farms increasingly will be offshore, especially in Europe. In Europe, offshore wind capacity is forecast to grow from just 4.5 GW in 2010 to 40.1 GW in 2020. This will mean a steady increase in the share of offshore installation in the total market in Europe, from less than 15% today to around 25% in 2020. The share would grow further, were it not for the increasing supplement to the onshore market provided by repowering.
With less ageing capacity, repowering will not be a major feature of the wind power market outside Europe, with the possible exception of the United States. Regional markets outside Europe will similarly show a shift in focus offshore, where the wind resource is available. Although a smaller proportion of non-European new installation is likely to be offshore than in Europe, without repowering, the offshore proportion of total installation is likely to be similar to that in Europe (25%).



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