DESIGN SYNERGY
“Generating tidal power is one thing, maximizing value in tidal resource developments is quite another. “ Martin J. Burger CEO Blue Energy Canada Inc.
There are a number of advantages to the Blue Energy Tidal Bridge System. Taken separately they are obvious factors and common sense, but when combined, they form a less obvious synergy that serves to optimize performance and costs of construction, installation, and operation and maintenance.
A propeller placed in a moving stream of water is subject to the limitation technically known as the Betz Effect (59.3% kinetic energy conversion limit). Fluids tend to flow around rather than through energy capture devices. What this means is that laws of physics handicap the bottom mounted underwater windmill conversion methods to only a percentage of their ambient stream kinetic energy potential. Blue Energy recognizes the unique nature of tidal hydrographic regimes and that power conversion outputs are a cubed function of the water velocity.
Flow shaping, static/current head, Betz Effect, resource by-pass – all subtleties in method yet to be appreciated in the early phases of tidal technology commercialization. By using thin shell concrete structure and rock fill causeway to develop blockage, we expand the kinetic energy capture ratio to achieve higher build efficacies. There are a number of advantages to the Blue Energy Tidal Bridge System. Increasing the channel blockage ratio develops a static head across the bridge (water levels are slightly higher on one side) allowing us to generate the maximum amount of energy. Incorporating the static head with venturi flow shaped turbine rotor bays also permits us to set the fluid media conversion velocities to just under the pressure limits for cavitation (remember power output is a cubed function of the water velocity), thereby developing maximum power for a given sectional area. It is these subtleties that will be the bottom line determining factors as to who will be left standing after the inevitable consolidation of the tidal power space.
Understandably, the above is difficult to understand, and a bit technical but necessary to explain Blue Energy’s power yields of potentially 400% to 1000% over that of bottom mounted free stream methods due to higher turbine density and overcoming the Betz Effect efficiency limitations with phasing and the creation of a hydraulic head.
ENERGY DENSITY AND PROJECT DENSITY
One of the key features that distinguish tidal energy from other renewable energy sources is inherent in the very nature of water. It is a universal, relatively heavy fluid substance with a high surface tension. Because it is 832 times the density of air it can carry many times the energy per cubic meter. These characteristics allow it to be strongly affected by the interplay between the earth and moon’s gravitational forces, causing the very regular and predictable rise and fall of tides. These tidal variations are amplified by land features into truly massive directional changes of water in many locations of the world.
Tidal energy capture devices have no need to employ giant blades with wingspans three times that of the largest airliner like the latest wind turbines. A single Blue Energy Ocean Class vertical turbine stacked module can generate twice as much electricity over the course of a year as the largest offshore wind turbine. Some of the best tidal energy sites will span ten kilometers or more and accommodate hundreds of power modules.
The energy density of water is the basis for the extremely high project density characteristic of the unique Blue Energy design. Whereas capturing the same quantity of energy from wind requires thousands of windmills placed over tens of thousands of acres, a Blue Energy tidal bridge occupies no more land than an equivalent length of bridge or highway. Similarly, solar energy is both widespread and lacking in density. It requires many square miles of desert to scale up to the output of a single Blue Energy tidal bridge.
The benefits of high project density are not limited to visual impact or land usage. Travel distance to perform routine maintenance is minimized. Instead of an extensive network of power lines, all power lines are located within the bridge itself. Our purpose designed crane can drive a short distance to work directly over a heavy machinery equipment room, whereas changing a generator on a 120 meter wind tower requires setting up a giant crane and performing an expensive and challenging operation. When the wind turbine is mounted offshore on a submerged tower, maintenance becomes even more expensive.
Underwater propellers or ducted fans have the same restrictions on energy density capture that wind turbines have, with the additional difficulties that result from maintenance discussed elsewhere. Few sites have the physical capacity to permit installation 1,000 underwater devices at one location even if the long-term maintenance issues were solvable.
In the US, and the rest of the world as well, burning coal is the most common means of generating electricity. Fossil fuels like coal do indeed contain a tremendous amount of energy per pound, but that does not mean that their overall system impact density is low. Everyone is aware that burning coal is detrimental to public health and the planet’s atmosphere, yet this cost is largely ignored by the market price system. The extent of physical impact is less widely recognized. In point of fact, more land is currently used in the US to produce electricity from coal than would be necessary to generate the same amount of power from solar panels.
TRANSPORTATION RESOURCE
The Blue Energy Tidal Bridge is both a mounting system for an array of large turbines and a bridge suitable for multiple lanes of traffic. It stands apart from every other energy production system in the world because of the multi-function synergies incorporated into its design. An oil well has only one use—to provide crude oil for a refinery, and nobody has yet been able to turn a wind turbine into a carnival ride! Design synergy exists along three dimensions—transportation bridge value, rugged design and ease of service, and creation of static head to negate the Betz Effect. The Blue Energy system is truly more than the sum of its parts.
As we respond to pre-commercial inquiries about our system we have found that some locations like the Chacao Channel in Chile or the Hangzhou Bay Bridge in China value a bridge crossing in the multi-billion dollar plus range. Affirming that the company is on the right track with its tidal bridge methodology, Blue Energy has already received in excess of $30 Billion in transportation tidal bridge solution inquiries from around the world. This distinguishes our conversion method and is an indicator that our tidal bridges will enjoy a billion dollar supplemental market driver. Billion dollar transportation sector propagation drivers and low price point, mean the Blue Energy technology will NOT require billion dollar subsidies (as did wind power) to move this technology very quickly into the energy mix.