Control Techniques inverters chosen for Aquamarine Power’s flagship technology.
The world’s largest and most successful working hydroelectric wave energy device, known as ‘Oyster’, has, at its heart, a 315 kW high-efficiency grid connected inverter system from Control Techniques.
Aquamarine Power’s Oyster marine energy generator sits just off shore, at Orkney, and comprises a large buoyant steel flap hinged to a base that sits on the sea bed. As waves roll over the device the flap oscillates backwards and forwards driving two hydraulic pistons attached to each side. High pressure water from these two pumping cylinders – clean, salt-free water in an enclosed system – is pumped ashore, driving a Pelton wheel with spoon-shaped buckets that harness the energy of the high pressure water. This is attached to a flywheel (to smooth out variations), powering a standard induction generator. Control Techniques inverters take the generated power and provide an interface with the grid.
Testing of the demonstration scale wave energy device commenced at NaREC in March last year. It is now installed and working offshore at Billia Croo near Stromness, in Orkney to generate power for the national grid and local homes in Orkney and beyond.
The more powerful the wave action, potentially the more electricity that can be generated from such devices, with the maximum output being in the winter months coinciding with maximum demand – it has been estimated that the biggest waves incorporate potential energy amounting to 200 kW per metre! Long term, marine energy has the potential to meet up to 20% of the UK’s energy demands. Control Techniques was involved in the development at an early stage, because of its close working relationship with the New and Renewable Energy Centre (NaREC) at Blyth, where the Oyster concept was under test in their dry dock facility.
Two Control Techniques inverters provide a clean supply to the grid, with low harmonic distortion, the AC output from the generator being equally split via sharing chokes to produce a clean output to the grid. Being a demonstration unit, Aquamarine Power has fitted many strain gauges, pressure monitoring and other feedback devices at all key points on the system to give a complete picture of performance and all of these signals are fed back to the PLC. The Pelton turbine’s speed is monitored by an encoder and this is fed back to the inverter.
“The next generation of Oyster drives, which will have three operating ‘flaps’, are already in development, and we are looking at an output of 2,4 MW per unit,” says Paul Smith, Lead Electrical Engineer at Aquamarine Power.
The units that make up the system are from the Unidrive SPM range which can be used to implement high efficiency grid-tie inverters for renewable energy systems including wave, tidal, photovoltaic and wind.
Decarbonising the energies and chemical industry without the risk Schneider Electric South Africa
Electrical Power & Protection
Schneider Electric argues that decarbonisation in Africa’s energies and chemical industry need not compromise production or profitability. A phased, digitally enabled approach, starting with energy efficiency improvements, can reduce emissions while strengthening competitiveness.
Read more...Modular UPS system with scalable, high-availability architecture
Electrical Power & Protection
Legrand South Africa has launched its fifth-generation TriMOD three-phase modular UPS, available from 10 to 80 kW. The system features hot-swappable modules, multiple input/output configurations, and up to 99% efficiency in Eco Mode, designed for data centres and critical industrial environments.
Read more...Why mining operations need local lightning early warning Senseca
Editor's Choice Electrical Power & Protection
Lightning can develop into a serious mining hazard before the first local strike, leaving crews little time to stop work and reach safety. Local early-warning technology can provide valuable lead time, allowing mines to connect developing storm conditions to defined trigger actions that protect people, explosives and equipment.
Read more...South Africa’s dirtiest fuel is building its most resilient boilers
Electrical Power & Protection
Steinmüller Africa argues that duff coal, the low-grade fines and discards stockpiled over decades, can now underpin reliable, compliant industrial boilers using mature circulating fluidised bed combustion technology, turning a long-standing liability into a phased energy transition pathway.
Read more...Retrofitting for sustainability Schneider Electric South Africa
Electrical Power & Protection
As budgets tighten and sustainability targets increase, retrofit and modernisation strategies are gaining traction across Africa, allowing organisations to upgrade only what limits performance while preserving existing infrastructure and extending asset life.
Read more...USB-Datalogger for voltage 0 to 30 V DC Vepac Electronics
Electrical Power & Protection
The PeakTech 5186 is a data logger for DC voltages from 0 V to 30 V with terminals on the top of the device.
Read more...Pole-top boxes for smarter, more secure electricity networks
Electrical Power & Protection
As South Africa accelerates the rollout of smart prepaid electricity metering, innovative enclosure technology from Power Process Systems is helping utilities improve network security, reduce electricity theft and protect critical electrical infrastructure.
Read more...Simplifying electrical design compliance
Electrical Power & Protection
Referro Systems highlights how Rockwell Automation’s Global SCCR Tool simplifies short-circuit current rating compliance for complex industrial electrical systems.
Read more...Engineering resilience into Africa’s energy future
Electrical Power & Protection
Zutari’s managing director of water explains how Burundi’s landmark Jiji and Mulembwe hydropower projects demonstrate what resilient, climate-adapted infrastructure delivery looks like – and what this means for Africa’s energy future.
While every effort has been made to ensure the accuracy of the information contained herein, the publisher and its agents cannot be held responsible for any errors contained, or any loss incurred as a result. Articles published do not necessarily reflect the views of the publishers. The editor reserves the right to alter or cut copy. Articles submitted are deemed to have been cleared for publication. Advertisements and company contact details are published as provided by the advertiser. Technews Publishing (Pty) Ltd cannot be held responsible for the accuracy or veracity of supplied material.
printer friendly version