Posts Tagged ‘Electrical generator’

Seabed electricity generator test

November 29th, 2009 admin No comments

Cardiff-based Tidal Energy Ltd is hoping to stage a year-long trial of its DeltaStream device off Pembrokeshire

Cardiff-based Tidal Energy Ltd is hoping to stage a year-long trial of its DeltaStream device off Pembrokeshire

A renewable energy company plans to test a new underwater generator just off the Pembrokeshire coast.

Cardiff-based Tidal Energy Ltd has planning permission for onshore works and is now seeking consent to place its DeltaStream device on the seabed.

A year-long trial is due to be held at Ramsey Sound, near St Davids.

The company said its tidal generator, capable of producing enough electricity to light around 1,000 homes, was at the cutting edge of green technology.

Invented by Pembrokeshire engineer Richard Ayre, each unit features three generators that sit on a triangular frame.

It is designed to be easily lowered onto and recovered from the seabed using a floating crane.

The company said its distinctive blade design enabled the turbine automatically to shed excess power, permitting consistently high energy conversion. best online casino .

The device will sit on the seabed at Ramsay Sound, near St Davids

Planning approval has been granted by Pembrokeshire Coast National Park Authority for the onshore works.

The company has now applied to both the UK and Welsh assembly governments for consent for the offshore works which include laying a cable and positioning one DeltaStream device on the seabed.

Chris Williams, development director of tidal energy, said a “comprehensive” environmental impact assessment had been undertaken.

A public exhibition of the plans is due to be held later this month.

The company is hoping to start the trial in autumn next year.

Mr Williams said: “The next public exhibition is to update the local community on the project, and particularly to discuss and explain the findings of the environmental assessments.

“Areas that have been assessed are far-reaching, ranging from bird life, to mammals, tourism and ecology.

“We invite anyone with an interest in the project to come along and talk with us about the details of the proposed 12-month test. online casino canada .”

The exhibition will be held from 1400 to 1700 GMT on Friday, 20 November and 1000 to 1300 GMT on Saturday, 21 November at Curtis House on Bryn Road in St Davids.

Electrical generator

July 22nd, 2009 Grace No comments

In electricity generation, an electrical generator is a device that converts mechanical energy to electrical energy, generally using electromagnetic induction.800px-modern_steam_turbine_generator

The reverse conversion of electrical energy into mechanical energy is done by a motor; motors and generators have many similarities. A generator forces electric charges to move through an external electrical circuit, but it does not create electricity or charge, which is already present in the wire of its windings. It is somewhat analogous to a water pump, which creates a flow of water but does not create the water inside. online casino canada . The source of mechanical energy may be a reciprocating or turbine steam engine, water falling through a turbine or waterwheel, an internal combustion engine, a wind turbine, a hand crank, compressed air or any other source of mechanical energy.

Today, the technology of electrical generator is to come to maturity, but its historic developments are complicated.

Before the connection between magnetism and electricity was discovered, electrostatic generators were invented that used electrostatic principles. These generated very high voltages and low currents. They operated by using moving electrically charged belts, plates and disks to carry charge to a high potential electrode. The charge was generated using either of two mechanisms:

Electrostatic induction

The turboelectric effect, where the contact between two insulators leaves them charged.

Because of their inefficiency and the difficulty of insulating machines producing very high voltages, electrostatic generators had low power ratings and were never used for generation of commercially-significant quantities of electric power. The Wimshurst machine and Van de Graff generator are examples of these machines that have survived.

In 1827, Hungarian Anyos Jedlik started experimenting with electromagnetic rotating devices which he called electromagnetic self-rotors. In the prototype of the single-pole electric starter (finished between 1852 and 1854) both the stationary and the revolving parts were electromagnetic. He formulated the concept of the dynamo at least 6 years before Siemens and Wheatstone but didn’t patent it as he thought he wasn’t the first to realize this. In essence the concept is that instead of permanent magnets, two electromagnets opposite to each other induce the magnetic field around the rotor. Jedlik’s invention was decades ahead of its time.

In 1831-1832 Michael Faraday discovered the operating principle of electromagnetic generators. The principle, later called Faraday’s law, is that a potential difference is generated between the ends of an electrical conductor that moves perpendicular to a magnetic field. He also built the first electromagnetic generator, called the ‘Faraday disc’, a type of homopolar generator, using a copper disc rotating between the poles of a horseshoe magnet. It produced a small DC voltage, and large amounts of current.

The Dynamo was the first electrical generator capable of delivering power for industry. The dynamo uses electromagnetic principles to convert mechanical rotation into a pulsing direct electric current through the use of a commutator. The first dynamo was built by Hippolyte Pixii in 1832.

A dynamo machine consists of a stationary structure, which provides a constant magnetic field, and a set of rotating windings which turn within that field. On small machines the constant magnetic field may be provided by one or more permanent magnets; larger machines have the constant magnetic field provided by one or more electromagnets, which are usually called field coils.