We refer to wind turbines as a mature technology – they are, and they are well proven as a reliable energy source as many countries, and even South Australia, prove by integrating 20% wind energy into their grid.
That doesn’t mean further innovation is possible, any more than the “mature” (century-old) automobile design relying on an internal combustion engine can’t be surpassed (as they now are, by electric vehicles).
As the renewable energy industry grows, we could see a huge creative engineering potential unleashed. Here’s three innovations currently being projected for turbine design, starting right here in Victoria – Geelong.
1. The Eco-whisper turbine
Geelong engineering company Austeng is testing a 20kW, near-silent turbine designed by Renewable Energy Solutions Australia, that would ideally be used on factory roofs to offset their energy use (but only interstate and abroad, if the state government keep their disastrous anti-wind turbine laws!).
The following is from an article by Kim Waters in the Geelong Independent, 15/7/11.
The Renewable Energy Solutions Australia (RESA) design aims to supply energy for factories, warehouses, ports, airports and schools.
RESA business development manager Michael Le Messurier said the 23-metre “virtually silent” turbine was rated at 20kW.
“The Eco Whisper turbine is unique with its 30 blades extending outward to from a 6.5-metre diameter central hub,” he said.
“The advanced dynamic slew drive eliminates requirement for a tail, allowing the turbine to operate in high wind speeds while facing the wind full-time. This avoids turn-away losses and results in increased power over longer time periods.”
Mr Le Messurier said Austeng was building a commercial prototype for on-site testing.
The company chose Austeng based on Industry Capability Network recommendation and its track record in “high-level projects”.
Mr Le Messurier said the turbine was also suitable for rural zones around Geelong due to the region’s “abundant wind resource”.
“It’s well-suited to urban development sites such as office buildings, apartments, industry parks, shopping centres and universities”.
If this technology goes ahead it could be great news for the regional economy – if the new wind farm planning laws don’t scuttle it. Geelong Trades Hall secretary Tim Gooden wrote in the Geelong Advertiser:
We have great companies in Geelong that are moving to deliver high-quality manufactured products for the renewable energy sector.Austeng is currently building the first silent wind-powered energy plant and IXL Blackwell is gearing up to supply solar power components to Western Australian power stations.
This is just the beginning of what is possible if the Australian Government moves in a positive direction now to ensure the billions of dollars to be spent on renewable energy are not all used on just buying it in from overseas. It would be almost pointless to have renewable energy by 2020 but no manufacturing industry and jobs to use the power.
2. The Wind Lens
A new idea from Japanese researchers is to concentrate the wind passing through the turbine, giving rise to the analogy of “lens”. If Japan moves away from nuclear energy and into renewables, that will be a huge boost for the industry globally. Clean Technica reports:
Professor Prof. Yuji Ohya of the Kyushu University research institute for applied mechanics (RIAM) has been working with a team to improve the efficiency of wind turbines. Combining an inlet shroud, a diffuser, and a brim into a wind lens, power output has been improved by a factor of 2 to 5 times in several experiments. Turbine noise is also decreased.
The Wind Lens works by creating an area of low pressure behind the turbine that essentially sucks the wind through the turbine, increasing effective wind speed. As wind power is proportional to the wind speed cubed, the wind lens changes the fluid dynamics around the turbine to increase its power.
The RIAM researchers anticipate the best use of wind turbines is offshore, where winds tend to be more constant and speeds higher. In an effort to promote the Wind Lens applications offshore, they have also designed a hexagon floating platform that could be used in conjunction with the wind lens turbine technology.
3. Double rotors
Finally, the following is from windpower engineering & development:
A novel turbine design uses two rotors of equal diameter, one each at opposite ends of a nacelle, to capture wind at greater capacity factors than conventional designs can do, say developer Airgenesis LLC (airgenesiswind.com). The developer says the rotors, offset from each other by 60°, will be turning at low speeds of 2.5 to 3.3 rpm, and are capable of producing 51 kW in wind speeds of about 5 mph. With a maximum of 3.3 rpm, it minimizes the possibility of harming wildlife. The low speeds also minimize the danger of ice throws. “All the high rpm speeds are inside the turbine,” explains company spokesman Clayton Troxell. At a wind speed of 15 mph, the design will be producing over 1 MW with a maximum possible output of 10.7 MW at 32 mph. The design has passed engineering proof of concept and is ready for licensing. Plans are already in the works to build and test a 10.7-MW unit by next year.
The Airgenesis design uses two rotors, one at each end of a nacelle. Gearboxes and generators mount at ground level for easier access.
There is more to the new design than two rotors. “Most of the heavy equipment is mounted at the base of the turbine so maintenance work can be simplified. Furthermore, using multiple generators provides the capability of replacing generators without shutting down the turbine. Clipper Windpower uses a design of four generators for similar advantages but mounts them in the nacelle. Troxell says many details covered by several patents are being held confidential. The design is said to target a constant electrical output at low wind speeds, conditions in which traditional wind turbines cannot operate.