Published on November 22nd, 2012 | by John I.0
The History of Power, The Advantage of Wind Power and Wind Farms
Wind as a source of mechanical power has been in use since time immemorial first used in sailboats and to run windmills to process salt in China. Windmills were used to pump water for ranches that did not have access to water in the US. Wind pumps featured a lot in the development of the train system.
Arising from the invention in 1887 by the Scottish academic Professor James Blyth, electricity was born in his garden. This was followed by rapid development in the generation of electricity by using turbines which initially produced energy in Kilowatts, which at the moment can produce up to 7 MW.
Wind energy arises from movement of the air across the earth surface. This energy provides a potential that is able to supply more power than is currently in use by people globally. A study shows that man can be able to extract up to 68 TW of energy.
Wind farms comprise a group of turbines that are used for generating electricity in the same location. Each wind farm may contain hundreds of turbines which cover extensive tracts of land. The land between these turbines may be put to use for agricultural purposes.
Each turbine has the same design behind it. They consist of a wind turbine which is set on a horizontal axis with a tri-blade rotor. The rotor is attached atop a tubular tower each turbine is connected with a power connection system of 34.5 Kv with a communications network to match.
When the wind farm has a substation, the medium -voltage will be increased by using a transformer which can help connect to high voltage power transmission lines. The biggest onshore wind farms can be found in the US. By the year 2002, the Alta Wind Energy Centre was the biggest in the world delivering 1020MW closely followed by the Roscoe Wind Farm which delivered 781.5MW. As at November 2010, UK’s Thanet Wind farm represented the largest wind farm located offshore, delivering 300W.
Which cables are used for Wind Farm Energy?
When you use a reliable and long lasting power cabling system for wind farm energy, you will get to improve your returns on investment. Cabling requirement is determined by the specifics required by the particular wind farm including the generation size and number of turbines.
Other factors include the length of the cable and cost of installation, predicted cable life and failures expected. Cross linked polyethylene (XLPE) is one material that is suitable for cable insulation. This cable is utilized widely in laying MV underground cables because they are of high quality, good cost, lower operating costs and durability.
Several studies have brought out the fact that XLPE cables used in UG applications last longer and will not age after being used for more than thirty years in use. They also have a lifetime forecast of forty years. Before using the cable, the wind farm needs to create specifications for the cable which is required.
The cable you select will enable you to have a reliable system that will help you achieve the best return on investment in the farm.
Helping to build Wind Farms using High XLPE Cables
With recent proposals for a huge new offshore wind farm in the Irish Sea being announced, it might be worth highlighting the pivotal role that XLPE cables play in these proposals.
The projected Rhiannon wind farm, situated between the Isle of Man and Anglesey, could see as many as 440 turbines built. The wind farm would be based somewhere around 12 miles north-east of Anglesey, and would also cover an area the size of the island itself. Within the next decade, it is possible that over a dozen sites around the UK could see offshore wind farms being built.
The plans for the Rhiannon wind farm, first announced in January 2010, would contain somewhere between 150 and 440 turbines. These turbines would ideally generate up to 2.2 GW of electricity, which is enough energy to satisfy the needs of around 1.7 million UK homes.
If permission is granted, construction could start in 2017. The National Grid is currently working on a strategy to improve its network to carry electricity from the proposed wind farm. The National Grid is accountable for transmitting electricity to towns and cities (the main centres of demand) from where it is generated (e.g. power stations and large wind farms). In order to facilitate this, a network of overhead lines and underground cables is used, which operate at high voltages (275 and 400 kilovolts (kV)). At these centres of demand the power is transformed to lower voltages for onwards distribution to homes and businesses through the regional electricity network by the network operator.
To enable the proposed wind farms, around 30 miles of pylons are being projected, including a new sub-station near Cefn Coch. Moreover, also amongst the proposals is a plan to replace three of the underground power cables in the Glaslyn estuary with 12.
The original 3 cables were installed in the mid-1960s, which drastically reduces the amount of power that can currently be transmitted. In order to create a second circuit, 12 new cables will need to be installed. These cables will be the more modern Cross Linked Polyethylene (XLPE), which are insulated using a cross linked polyethylene material. A simpler overall cable construction is possible due to the absence of fluid in the cable insulation; the XLPE cables also require less maintenance. They have now become the standard cable technology type used for new installations and would be the type employed at the Glaslyn Estuary.
Companies such as Eland Cables UK can supply XLPE cables that can be installed in power networks, underground, outdoors and in cable ducting. They can also be used where fire, smoke emission and toxic fumes can create a potential threat.