| Small hydro
These machines are from Gilkes’ Compact range and were ideally suited due to their simplicity and ability to maintain efficiency across the varying hydrology (both head and flow). The machine’s compact footprint, high speed and robust construction also make it an ideal match for the site’s requirements. The new machine will be installed in late 2023 with commissioning scheduled for January 2024. It will be skid mounted so that assembly, cabling, and alignment can be completed in Gilkes’ factory. This has the added benefit of reducing the timescales for onsite installation and commissioning. In terms of operation the main hydro minimum load is always above 15kW, so the new machine will be connected in parallel to the local network feeding the existing hydro that provides power as baseload. This will result in reduced energy waste, control system requirements, monitoring of the equipment and reduced start/stop events for the new system. South Georgia plays host to over 5000 visitors a year and has become one of the world’s most exclusive destinations for environmental tourists, as well as being home to an extraordinary amount of wildlife, including seven million penguins. Both hydro installations on the island have been designed with the environmentally sensitive area and local wildlife in mind. The main power station is very quiet; the main sound being the water in the tailrace in the bottom of
the building as it makes its way to the sea. Power demand at King Edward Point and Grytviken now runs almost entirely on the existing hydro. Diesel generating sets are for emergency back up only and to cycle the fuel storage. The use of diesel is not the most eco-friendly solution and has the added problems of ongoing cost, safe transportation, and storage, hence the installation of a second micro hydro to ensure the future of renewable energy on the island. Gilkes will also supply annual technician training to the British Antarctic Survey to enable them to run and maintain the equipment.
Turbine Selection Turgo Impulse turbines were selected for both hydro
installations at Grytviken. The Turgo is ideally suited to this application as it maintains efficiency over a large flow range and is of a proven and rugged design. The standard range of Turgo turbines that Gilkes manufacture range from 7.5” – 43”, so the machine at Grytviken will be by far the smallest in terms of output in recent years. Although equally happy here, these Compact 7.5” machines normally operate under greater heads and flow rates and are usually configured in the 30kW to 100kW range. The flexibility of the Turgo runner results in a machine that is suitable for an extremely varied operating envelope. Gilkes conventional range of Turgo turbines which
are more commonly found in the 500kW to 5MW range provide a specialised and cost-effective solution where there is a combination of medium head, varying flow rates and the requirement for a compact package with minimal operational and maintenance requirements. ●
Turbine data Above: Original 13.5 Twin Jet turgo installed in 2008
Stats Turbine 1 Customer: Morrison Construction Head: 65m Flow: 472 l/s Turbine type: Gilkes Twin Jet Turgo Output power: 250 kW Dia: 13.5” Speed: 1000 rpm Commissioned: 2007
SCOPE OF SUPLY Gilkes 13.5” Twin Jet Turgo Turbine Hydraulic Control Module Main Inlet Valve with actuator Electrohydraulic Governor System Synchronous Generator with Flywheel Control Panel Head level sensor Installation & Commissioning
Stats Turbine 2 Customer: Government of South Georgia and the Sandwich Islands Head: 61m with significant head losses due to use of existing pipework Flow: 42 l/s Turbine type: Gilkes Single Jet Compact Turgo Output power: 13 kW Dia: 7.5” Speed: 1,500 rpm Commissioned: planned in 2023, depends on site work completion
CAD Model 7.5in Turgo
SCOPE OF SUPLY Initial Feasibility and Technical Support Pipework upstream of Main inlet Valve Main Inlet Valve with actuator Gilkes 7.5” Single Jet Compact Turgo Electronic Governing System Induction Generator Skid Mounting Control Panel Base Station Transmitter Local Control and Power cables Head level Sensor and Cabinet Installation & Commissioning
www.waterpowermagazine.com | March 2023 | 27
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53
