Making Waves Around the Globe

Minesto's Deep Green tidal power technology is small, lightweight and very efficient and is able to accelerate the water velocity by up to a factor of 10

Writers Emily Jarvis
Project Manager Dave Alexander

Minesto is a marine energy technology company with a patented technology for cost efficient electricity production from tidal and ocean currents. Minesto's award winning product, Deep Green, is the only known marine power plant that operates cost efficiently in areas with low velocity currents. Deep Green resembles an underwater kite with a wing and a turbine that is attached by a tether to a fixed point on the ocean bed, moving swiftly in an 8-shaped trajectory in the current.

Compared to other traditional and renewable energy sources, tidal and ocean current energy is considerably more predictable and reliable; with minimal visual, noise and environmental impact. Marine energy from the world's ocean has huge potential. Deep Green, with its low weight and ability to operate in low velocity currents, has several advantages compared to other tidal and ocean current power plants; the catchment area is much larger, and service and maintenance is more cost efficient, resulting in low electricity production costs, comparable with traditional energy sources.

Minesto was founded in 2007 by Managing Director Anders Jansson, Saab Group and Chalmers University of Technology, with its base in Gothenburg, Sweden, and Northern Ireland, UK. The major shareholders in Minesto are BGA Invest, Midroc New Technology, Saab Group and Chalmers University of Technology.

"We started the company as the technology we have can significantly reduce the material usage for tidal power, and unlock a low velocity resource, whilst still maintaining a very high efficiency. This places us in a position where we can produce cost efficient electricity at low velocity sites, which are more common around the world than high velocity," says Jansson. "Compared to other tidal solutions, we weigh on average 14 tonnes per MW, whereas other solutions can weigh up to 300 tonnes per MW ," he adds. As you can imagine, this significant reduction of material required to construct the tidal power structures also means that the capital cost per MW is lower, benefitting Minesto investors and shareholders but more importantly, the electricity consumers.

The Advantages of Low Velocity Tidal
Cost is not the only advantage for low velocity tidal power. Since the Deep Green product is lightweight, the technology is easier to install, service and maintain as Jansson highlights: "We can use very small vessels in order to repair and maintain the structures, which decreases operational costs for us and uses less energy to repair. Also, it is easier to insert the cabling required into the ocean floor as the seabed is often softer than in areas where high velocity tidal is installed."

Tidal power has been a growing contributor to the available renewable resources, specifically in the UK. A 2007 study - entitled Assessing the Feasibility of Adapting the Minesto Device to Low Energy Tidal Steams - revealed that alongside the Deep Green technology, Minesto had the ability to increase the potential tidal energy in the country by 100 percent. "Again, this is because we can unlock potential areas for our technologies where others cannot. We are looking to install in areas with 1.5 metres per second tidal velocity, whereas the rest of the industry target 2.4 metres per second and above. As a result, we hope to double the tidal sector in the UK and as the industry grows, as will the demand for tidal power and our own subsystems," emphasises Jansson.

Although tidal is still considered by some as a niche area, Jansson feels strongly that it will play a key role in the renewable future of not just Europe, but the world:"In order to make the transition from fossil fuel to renewable energy, there needs to be a mix of different sources, and I feel tidal will play an important role in this shift; specifically due to its predictability and ability to balance the grid with a reliable source of clean energy," he continues: "In terms of ocean current, our tidal technology has the same level of up-time as a nuclear power plant, which is sure to play a huge role off the coast of Florida, Australia, parts of Asia and even East Africa."

Proving the Impact of Tidal Power
The ocean is a harsh environment and subsequently, finding the right materials for construction and being able to test them is a key challenge when it comes to tidal energy. "People need to understand that conducting ocean testing is a cost-intensive, arduous and time consuming process, which means investors need to see any investment in this sector as a long term one."

As a consequence of this common misconception, Minesto work with two organisations in order to give tidal power the attention it deserves: The Marine Strategy Board at Renewable UK and the European Ocean Energy Association. Furthermore, the company produce regular press releases worldwide in order to educate the appropriate bodies of the different steps they are taking to boost the profile and possibilities of tidal energy. "Indeed, the industry still has a lot to prove, it is still in its infancy. However, our planned 10MW demonstration array in Wales, UK, is drawing a lot of attention which is certainly exciting," cites Jansson. This Deep Green technology site will go into full construction in 2016 and be finalised in 2019.

Moreover, Minesto are currently working with SNMREC – a part of Florida University research – in order to install their devices off the coast of the country in the US. "In Chile, we are also looking at our Deep Green technology as a possible solution to drive down the cost of electricity here; as the country currently makes heavy use of diesel generators," comments Jansson. Additionally, the company are working with a university in Taiwan in order to install a demonstration Deep Green tidal structure, following with commercial construction within five years. "We see Asia as an area with great potential for tidal power, we have a big interest in Korea and Japan and are currently exploring our options there. Minesto is still a young company, and has much more to offer given the right opportunity," he adds. Nevertheless, Jansson considers the UK as Minesto's home market, predicting faster growth in the next five years accordingly.

"We have a considerable amount of hours in the water and have proven that our low velocity tidal technology works. The Deep Green technology solves a significant number of issues that the ocean presents and this solution is very different from anything else in the market," Jansson surmises. Minesto's technology is small, lightweight and very efficient and is able to accelerate the water velocity by up to a factor of 10. This has a positive impact on installation, service and capital cost, thereby providing the end customer with low cost renewable energy, accompanied by a technology that has the potential to more than double the tidal energy opportunities on the globe.