SDE (Israel) has received approval for the 100 MW sea energy conversion project the company is planning to build on Kenya's coastline. The power plant will produce power at a production cost of about USD 0.02 per 1 kW of power. All generated power will be bought by Kenya Power & Lighting Company.
Minesto, a Swedish and UK company, showed off its tidal power technology in a video presentation demoed for the first time at Cop 15. The video shows a vision for the future of marine energy power plants, featuring a tidal power plant using Minesto's technology for harnessing energy from low-velocity tidal currnets.
Theoretical models, simulations and model tests have been done earlier, and have proven the power plant's ability to harness ocean tide energy. The next stage in the development of this technology is the installation of a prototype machine off the coast of Northern Ireland in 2011.
The technology, Deep Green, can be explained in two ways, according to Minesto. The first stage is the increase of relative flow speed, when water is entering the turbine. With the oncoming tide, a lift force is created, pushing the kite upwards. The kite is secured to the ocean floor with a tether and controlled with a rudder. The second stage is the generator which converts kinteic energy into electrical energy. Here's demonstration video featuring the new technology:
The development of tidal power plants is crucial for the future of renewable energy. According to BWEA's document, The Benefits of Marine Technologies Within a Diversified Renewables Mix, an optimal ration between marine and wind energy is 40/60, in order to reduce the cost of backup systems, reserve capacity and fuel costs. Additionally, this would allow developers to avoid redundant investments in capacities that won't be needed. A total of GBP 1 billion per year of cost reductions from an optimal energy mix can be achieved, according to this report.
Minesto is company owned in majority by Saab Group, and Midroc New Technology, Verdane Capital and Chalmers University of Technology.
Levitating vertical axis wind turbines might become the solution for the ever growing demand for electricity. Let's revisit the concept in a few lines.
Levitation is achieved by using permanent magnets placed in strategic locations to provide "lift" for the vertical axis turbine. This allows the turbine to hover above the ground (levitate), and thus produce no friction while it spins. Friction is one of the most influencing forces that reduce the power output of any machine with moving parts. Eliminating this reduction factor can greatly improve a machines efficiency. This is the Maglev turbine's advantage (Maglev = magnetic levitation). According to some sources, a single large Maglev turbine can output as much as a gigawatt of power (enough for about 750,000 homes), which is an enormous increase over the largest conventional wind turbine capacity today of about 6 MW. Operating wind speeds range from low (1.5 m/s or ) to very high (40 m/s), making this wind turbine an efficient power generator across a wide range of wind speeds. Once commercialized, Maglev turbines could increase power generation by 20% compared to conventional turbines, while reducing operating costs by as much as 50%!
Here's a video from Regenedyne explaing the Maglev wind turbine:
Currently, there are projects being developed in Northern China by ZK Energy, where Maglev turbines are to be used for rural area electrification. There is now news whether anything has been completed yet.
Full Permanent Magnetic Suspension Wind Power Generators, as they are also called, represent a very promising future for wind power generation. It remains to be seen how the machines actually perform in actual installations. Requiring a relatively small area of land for operations, about 100 acres, these wind power generators have another advantage over conventional wind turbines – they take up less space, so there is less negative impact on the surrounding landscape.
Underwater currents (or rivers, sometimes called) represent a powerful source of energy in the ocean. Basically, water currents under the ocean's surface have plenty of motion energy. Tapping into this energy could be done using underwater hydro-turbines. Several problems exist, one of the most important ones being there is no detailed data on the behavior of underwater currents, not yet anyway. There has been research within this subject over the years, but a useful "current map" wasn't available. Until now, that is. Researchers from the Center for Ocean Energy Technology (COET, Florida Atlantic University), have successfully developed and now deployed a method for gathering baseline information for characterizing in more detail the spatial and temporal variability of the Gulf Stream.
COET deployed four Acoustic Doppler Current Profilers (ADCP) morrings in the Atlantic Ocean, right off the east coast of Florida, about 8 to 36 km from the coastline, at depths of about 221 to 645 meters. The Gulf Stream is the most energy dense ocean current, and getting this data will mark a major development in ocean energy development.
ADCPs use high-frequency, low-power sonars to measure water velocity throughout water columns at single locations, and it does so every thrity minutes. The devices are going to deployed for a period of eight months, which should result in quite a lot of data, making the profiling process quite accurate.
For more info or illustrations of the ADCPs, visit their site. We've embedded their deployment video below which shows and explains in quite enough detail the whole operation as well as the concept and a little bit of theory. Enjoy!