Skip to content

THAWT (Transverse Horizontal Axis Water Turbine) | Most Efficient Underwater Ocean Turbine

THAWT is a water turbine that harnesses the power of running water to create electricity. It’s the most efficient water turbine around. Transverse Horizontal Axis Water Turbine (THAWT) was invented by French engineer Henri Giffard in 1851 which uses the natural force of running water to create electricity.

An underwater turbine is a device designed to extract energy from the flow of water. The new THAWT system captures the kinetic energy from flowing water and turns it into electricity, harnessing the power of the water’s motion. With just a few feet of drop, it can generate an incredible amount of electricity. In this article, we explain how they work and how they are used.

Introduction to Tidal Energy

Tidal power is one such developing technology, which harnesses the kinetic and gravitational potential energy in tidal streams. When compared to other renewable sources, tidal streams are a relatively reliable source of energy, as tidal movements can be accurately predicted in terms of direction, timing and magnitude. The rapid development of devices for tidal energy exploitation is being encouraged by government initiatives and by private investment.

Underwater Tidal Power plant - Clean energy fuel
Underwater Tidal Power

The horizontal axis, axial-flow turbine is the most common design of a tidal stream turbine. A number of variants of this type of device, which incorporate features such as flow-guiding shrouds or specific mounting techniques, have been proposed by different developers, but the underlying hydrodynamics remain similar for these devices. However, a drawback with such designs is that their size cannot be increased significantly, because the limited depth of flow at most sites restricts their diameter. Tidal stream energy is likely to be more expensive than either other renewable resources or combined cycle gas turbines, until at least hundreds of megawatts capacity is installed.

The importance of clean energy

Types of clean energy available in the market
Clean Energy

Clean energy is energy that is generated by renewable, zero-emission sources that does not damage the environment.

There is some overlap between clean energy and green or renewable energy sources, but not much. To grasp the distinction, one must first grasp its meaning.

What Is “Clean Energy”

Clean energy comes from sources that don’t pollute the air, whereas green energy comes from natural sources. Even though they are frequently referred to as the same, these two energy sources vary somewhat.

Renewable energy is produced from continuously replenished sources. Wind and solar energy are examples of renewable energy sources that will never run out.

While most green energy is renewable, not all renewable energy is green. For example, hydropower is a renewable resource, yet others say it is not green due to deforestation and industrialisation associated with hydro dam construction.

The ideal clean energy balance includes green energy and renewable energy sources like solar and wind.

The following is a quick method to memorize the differences:

Air = clean energy

Nature’s energy = green

Recycling = renewable energy

What Is It?

Clean energy generates electricity without harming the environment by emitting greenhouse gases like carbon dioxide. Wind, hydro, and solar energy are all renewable sources of energy.

Why is it Vital?

The environmental advantages of clean energy are paramount in a global energy future. Clean, renewable fuels not only conserve natural resources but also decrease the danger of environmental catastrophes like fuel spills or natural gas leaks. With fuel diversity, various power plants utilizing diverse energy sources can generate dependable power supply, guaranteeing enough to satisfy our needs.

What Can Be Done With Clean Energy?

Depending on the source of the energy, clean energy may be utilized for anything from power production to water heating.

Solar energy may be utilized for lighting, power generation, water heating, cooling, and more. Solar panels absorb solar energy and convert it to electricity. Solar panels are often used to charge batteries and many people currently utilize solar energy to power tiny garden lights. This same clean energy technology may be scaled up to bigger panels that power houses or other structures, or even numerous solar panels that power whole cities.

Water is a clean resource with unexpected uses. Hydroelectric power facilities, for example, use water from rivers, streams, or lakes to generate energy. Water is also used in towns and cities through municipal pipelines. Every day, millions of gallons of water pass through pipes in houses, generating energy for household and other uses. As generators grow smaller and cheaper to construct, this usage of municipal water becomes more common.

Wind power is generated by connecting a windmill to a generator. A long time ago, this kind of energy was used to crush grain or pump water, but it is now increasingly utilized to generate electricity. Onshore and offshore wind farms are becoming more common, but wind power may also be utilized to generate energy on a much smaller scale, even to recharge mobile phones.

Other renewable energy sources include geothermal, biomass, and tidal power, all of which have their own advantages and uses.

Clean Energy’s Future

In recent years, more renewable energy capacity has been built worldwide than new fossil fuel and nuclear capacity combined. More over a third of worldwide electricity capacity is now renewable. This development may be seen in the fact that the UK has now been powered solely by renewable energy for two months.

Renewable energy sources are the answer to delivering sustainable energy solutions while also preserving the earth from climate change.

Clean energy adoption is not only a nationwide trend; communities and municipalities are implementing laws to promote renewable energy usage. As more towns strive for 100% renewable energy, businesses are buying record amounts of renewable energy.

Because fossil fuels are limited, it makes logical that the future is renewable, and that renewable sources will continue to expand, lowering costs.

How Can Clean Energy Help?

Humans have been utilizing fossil fuels for nearly 150 years, and with increasing usage came rising emissions of greenhouse gases. These greenhouse gases trap heat in the atmosphere, raising global temperatures. Extreme weather events, changing animal habitats and populations, increasing sea levels, and other effects are all symptoms of climate change.

Renewable energy sources don’t contribute to global warming since they don’t produce greenhouse gases like CO2. These renewable sources slow climate change, while reforestation may help repair the harm already done, reducing global warming.

Can Renewable Energy Replace Fossil Fuels?

Given that people have been using fossil fuels for decades, the transition to renewable energy is relatively new. This uncertainty is attributed to renewable energy sources not yet meeting global electricity needs. This implies that carbon-based energy is still supplementing renewable energy.

However, it is thought that effective storage of renewable energy can balance our energy requirements. Experts believe clean renewable energy may replace fossil fuels by 2050 if clean renewable energy infrastructure and storage capacities improve.

Can Clean Energy Aid Our Economy?

Clean energy has financial advantages, not least because it creates jobs to upgrade infrastructure, produce clean energy solutions, and install and maintain them. As the globe moves away from fossil fuels, new possibilities will open up in areas like eMobility, electricity production, and storage.

Others with experience in creating future generation power solutions may profit from labor and contracts from those that are reluctant to adopt renewable energy.

Of all, the financial benefits of clean energy are secondary to the overall goal of improving the planet’s future. Clean energy is excellent for the environment, but it is also good for business. As fossil fuel usage decreases, so will the accompanying financial benefits.

Just how common is underwater wind turbines?

When you think about wind turbines, you likely picture a large structure placed atop a hill or mountain. Wind turbines have been around long enough that we have probably all seen one at some point in our lives. However, did you know that it is possible to place a wind turbine underwater? Not only does this create an interesting visual, but it also allows the turbine to harness power from winds located below the surface of the water.

GE OpenHydro Underwater Turbine

The GE OpenHydro turbines, which have a diameter of 16 meters, will be located 35 meters below sea level and 16 kilometers off the coast of the France. As the tides come in and out, two massive turbines measuring 16 meters in diameter and located 35 meters below sea level will be spun by the movement of the water. The turbines produce power using direct-drive permanent magnet generators and transmit it to an undersea converter for further processing and distribution.

GE OpenHydro Underwater Turbine
GE OpenHydro Underwater Turbine

Orbital Marine Floating Tidal Energy

The Orbital marine O2 platform is built around a tube-like ship that is permanently connected to the seabed via chains, rather than being attached to the bottom firmly. The O2 tidal turbine, which was built using Orbital’s technology, will be the world’s most powerful tidal turbine when it begins operating in 2020. On O2, the ability to adjust the blade pitch 360 degrees allows for the extraction of power from both tidal directions. The pitch-change system has been developed to accommodate bigger blades on future turbines, which will be more common. The use of hydraulic actuators allows the turbines to be swung to the surface for easier access and maintenance.

Floating Tidal Turbine
Floating Tidal Turbine

Water Wheel Generator


Using the energy of flowing water to generate electricity is not a new idea. Humans have been harnessing the power of water for millennia, beginning with ancient civilizations that used water wheels and progressing to the massive Hoover Dam.

The fact that these generators need little to no maintenance is a significant advantage. Also important is the ability of the generators to operate at low head. The spinning components of the hydropower generators are limited to just two. They are quite quiet, which makes them less annoying when they are close to a residence.

The generator is delivered as a fully assembled and operational unit. This eliminates a great deal of the technical work that the ordinary homeowner would have to undertake in order to implement the system.

This generator, on the other hand, is advised to have a head height of 25 feet and a pressure rating of 9 PSI in order to operate at peak efficiency.

How Does a Free Flow THAWT Underwater Turbine Work?

Very simply, it works like a wind turbine, but the blades are moved by a water current instead of by the wind.


What is an Underwater THAWT Turbine, and how does it work?

Turbines, in general, are devices that extract energy from the wind. In a similar vein, underwater turbine or tidal stream turbines harvest energy from the movement of the ocean’s water. Windmills harness the kinetic energy (KE) of flowing water, while wind blades harness the energy of moving air.

When compared to a conventional turbine, the underwater turbine operates on a similar concept. A set of blades will generate electrical energy that will be converted from mechanical energy that will be transported with the aid of an aqueous water flow.

Tides are mostly utilized to force water away from slanting blades, causing them to spin in the process. The current in the ocean varies depending on the depth of the water. Because of the large quantity of water strength in the air, this kind of turbine has a sluggish rotation. Turbines are placed inside an ocean and are covered with slippery materials such as Teflon or other nonstick coatings.

Principles of Operation of an Underwater THAWT Turbine

Turbines, gearboxes, generators, cables, and support structures are all required components of an underwater turbine system. When the water flows, the rotor spins, causing the generator to switch on and become operational. In order to adjust the rotational speed of the rotor shaft to the desired output speed of the generator’s shaft, a gearbox must be installed in between.

Through the use of wires, the produced power may be transferred to the surrounding area. The turbines have the ability to convert kinetic hydro energy into electrical energy. An underwater turbine is made up of a number of blades that are placed on a hub, as well as a generator and a gearbox to generate electricity.

It is possible that the impact of hydrodynamics on water flow will force the rotor to spin, thus turning the generator, which is connected to the rotor via a gear box. For the most part, the gearbox is utilized to convert rotational speed of the rotor shaft into desired output speed of the generator shaft. The energy generated may be sent to the land by means of transmission lines.

Transverse Horizontal Axis Water Turbine (THAWT): A new form of energy production

The Transverse Horizontal Axis Water Turbine (THAWT) has been proposed as a tidal device which can be easily scaled and requires fewer foundations, bearings seals and generators than a more conventional axial-flow device. The THAWT device is a horizontally deployed variant of the Darrieus cross-flow turbine, in which the blades can be oriented into a truss configuration to produce long, stiff multi-bay rotors.

A fluid particle passing through a Darrieus cross-flow turbine encounters two sets of blades. One on the front side of the turbine as the fluid enters, and again on the rear side as it leaves.

This increased stiffness and strength allows longer units to be constructed, and reduces the overall costs of foundations, bearings, seals and generators. A full scale device might have a diameter of 10 – 20 m and would operate in a flow depth of 20 – 50 m.


The THAWT device employs a truss design of blades, which is intended to increase the rigidity of the structure, so that it can be stretched across a channel without significant increases in blade stresses.

The Thawt device is mechanically far less complicated than anything available today, meaning it would cost less to build and maintain. “The manufacturing costs are about 60% lower, the maintenance costs are about 40% lower”.

The size of thawt is not limited by the depth of water in which it is situated, and the need to intersect the largest possible area of current has been incorporated into the design. Power generation of up to 100 MW could be achieved by an array of only 10 THAWT devices.


The Advantages of THAWT Underwater Wind Turbines

For comparison, if thawt devices were extended across the same area of current as axial flow devices, THAWT would require:

  • Less generators,
  • Less primary seals, and
  • Less foundations

and consequently thawt would incur:

  • Lower capital costs
  • Lower maintenance costs, and
  • Lower operational costs


Let’s face it, the ocean is a pretty big place full of some of the most powerful forces on earth. This makes harnessing its energy difficult, but that doesn’t mean it isn’t possible. The THAWT turbine has been designed to capture ocean currents and convert them into usable energy to power homes and businesses worldwide, as it doesn’t require any fuel to run.

In conclusion, as future technology of clean energy becomes more efficient, we will be able to harness the power of underwater turbines and produce electricity without damaging our marine life. We invite you to learn more about this revolutionary turbine by commenting below or by visiting our website today.


  1. Green energy
  2. Guardian – Tidal power
  3. Renewable Energy

Leave a Reply

Share to...