Blue Tidal Energy

Efficient, low maintenance tidal energy turbines

Blue Tidal Energy is a tidal stream turbine developer for generators to extract energy from the sea

What we do

Anyone who has any involvement with the sea will realise the level of energy that is available, free of charge, from the movement of water in the seas and oceans around the world. The amount of energy available is not only enormous, it is totally reliable.

Unlike solar and wind energy, the level of energy available at any particular location and any particular time is known decades in advance..
Unlike solar and wind energy the environmental impact is, or can be, virtually zero.

The majority of current tidal turbine developers have chosen
a route of using existing wind technology devices to steer their projects.

The business thinking of adapting existing technology and using the experience gained in a similar industry is normally a good one.
However, sometimes a step aside to look at the problem from a different angle is also useful. Blue Tidal Energy (BTE) has used the latter approach and is developing a turbine that has largely been ignored by the existing mainstream tidal energy companies.



Current thinking

Axial Flow - used by many energy companies

Most existing tidal energy companies use an axial flow turbine.

This turbine is very similar to the wind energy turbines we see around our countryside and out at sea.

The turbine is much modified for use in water and is positioned for energy extraction on the sea bed.
These devices have to cope with changes in direction of the tide, variations in strength of the tide including regular periods of zero tidal flow. They have controls which manoeuvre the orientation; pitch angle and rotational speed to suit the conditions. These devices also have to cope with long period under water with motors, generators, actuators and electrical connections completely submerged.

The resulting high maintenance costs are, not surprisingly, causing the industry to produce low return on investments.

Vertical Axis Turbine - The efficient, low maintenance way forward

Rather than the water flowing along the axis of the rotating blades, water flows across the axis of the Vertical Axis Turbine (VAT). The turbine can be mounted vertically or horizontally.

The first operating turbine in this configuration was the Darrieus turbine and then the more recent Gorlov Helical Turbine in 1995. Both of these inventions have their problems and have therefore not been adopted by the tidal energy industry.
Blue Tidal Energy has developed a new Vertical Axis Turbine by varying the blade pitch using a simple system requiring no power of any kind.

Advantages of the BTE turbine:

1. Mounted vertically with the top of the vertical shaft out of the water allowing all electrics to be above the water or near the surface for easy access.

2. The efficiency of a model variable pitch Vertical axis tidal turbine has been measured at just less than 50%, a figure verified by the Norwegian University of Science and Technology. This is as efficient as the most efficient modern wind and water axial flow turbines.

3. An efficiency of 32% to 40% has been achieved from the first test programme without a diffuser. Turbines mounted in a diffuser can achieve much higher efficiencies.

4. Axial flow turbines have a theoretical maximum efficiency of 59% (Betz law). The BTE turbine is not limited by this condition.

5. Rotates in same direction with flow from either direction, therefore no blade orientation motors required.

6. Water turbines needs to operate from a tidal flow of zero to full flow twice a day. Our variable pitch blades have eliminated the problem with self-starting for the VAT.

7. The frontal area presented to the water flow for VAT is square or rectangular. This shape allows better use of a tidal flow than a circular shape presented by the axial flow turbine. This factor is important when operating in shallow waters in an array.

Commercial Objectives

The Government has realised the importance of tidal energy. The little environmental impact and the reliability of the energy is becoming more important as the solar and wind energy boom begins to wane.

The Government's way of steering the source of green energy comes from its imposition on the electrical utility companies to provide more green energy and also from a particular type of technology.
The utility companies have to provide Renewable Obligation Certificates (ROC's) to the Government for every unit of power they distribute. The Government has increased the value of tidal energy ROC's to 5 times that of energy produced by wind and solar.

The current concept consists of single units that produce power in the 300kw range. These basic units can then be set up with 4 units on each platform to produce 1.2MW and then an array of 24 platforms to produce a Government maximum (for maximum subsidy) of 30MW.

Levelized Cost of Electricity (LCOE) is estimated to be £120-£140 with a capex of £2M per MW

Calculations using a site with a maximum stream flow of 2.7m/s produced energy over a year with a value of £14M at the subsidy recommended by the recent Energy Bill.


Internal resources will be used for the initial stages of testing with scale turbines and mounting platforms. However, as the project grows, outside finance will be required:

1. Government Grants

2. Individual Investments including crowd funding

3. Corporate Investments

Are you interested?

We are looking for a variety of resources and would welcome any contribution or discussion from interested parties.

If you are interested please contact us.