How can real-time data help wave power development?

Matthew Farmer 15 February 2021 (Last Updated February 12th, 2021 14:44)

Despite its huge promise, wave power makes up a tiny portion of global generation. Developers struggle to prove its worth and raise the profile of a long-promised technology. However, a piece of upcoming software promises to “put an end to some of the prevailing problems in the wave energy industry”. How effective can this be, and what is still holding wave power back?

How can real-time data help wave power development?
It is difficult to tell if the rise of solar and wind has had a detrimental effect on ocean-based energy generation, since all have benefitted from the energy transition. Source: Scottish Goverment

Since its inception decades ago, wave power has watched a green tide roll in. But this rising tide has not lifted all boats equally, and all forms of ocean-based energy remain underdeveloped.

Most ocean-based energy generation and development comes from tidal power, stemming from the gradual swell of changing tides caused by the moon. Wave power takes its energy from waves, in turn whipped up by the wind.

According to a report by the International Renewable Energy Agency (IRENA) released in December, installed wave power capacity reached 2.31MW in 2020. However, the report states: “Wave energy devices are rapidly increasing in size and power output, and around 100MW of new instalments can be expected in the coming years.”

Development companies generally rely on small projects, aiming to push the technology forward for greater competitiveness. Swedish company Eco Wave Power is one of these developers, focusing on quay-side wave power generators. Launched in 2014, its trial project in the Port of Jaffa, Israel, generates 100kW for the country’s grid. A partnership with EDF signed at the end of 2019 will see its expansion.

In an effort to prove the cost-viability of the technology, the company developed the beginnings of a 5MW project in Gibraltar. This cost $450,000, financed via a power purchase agreement. Since October, the company has moved forward with planning on projects in Vietnam, Australia, and Morocco.

Also in October, the company announced a “game-changing” piece of software to monitor wave power generation in real time. CEO Inna Braverman said: “With this software, Eco Wave Power will put an end to some of the prevailing problems in the wave energy industry – which significantly affect commercialisation efforts.”

How much of a problem is wave power commercialisation?

Wave power’s small scale leads to small scale developing companies with greater consequences for failure. Since 2000, the Government of Scotland has spent more than $271m (£200m) backing wave power projects on its coasts. In 2017, this had only led to unsuccessful trials and two wound-up companies.

A study by the University of Strathclyde and Imperial College London attributed this to several factors, “most notably a premature emphasis on commercialisation and a lack of knowledge exchange”.

The IRENA report states: “Ocean energy project risk assessment should create awareness on the technology reliability and raise trust among investors, who may be reluctant to provide financing in this sector. Ocean energy technologies are in major need of funds to push technologies towards the commercial stage.”

It is difficult to tell if the rise of solar and wind has had a detrimental effect on ocean-based energy generation, since all have benefitted from the energy transition.

Braverman told us: “Generating electricity with our technology is done at a significantly lower cost compared to offshore wave energy developers, but debt financing for such projects is still lacking, while financing is a key factor in rolling out the technology at scale.

“We believe that part of the lack of debt financing for the wave energy sector is due to the novelty of the sector in comparison to other renewable energy sectors such as wind and solar. Due to the novelty of the sector, there is currently no universally accepted way to determine the efficiency of a certain wave energy project or forecast the energy to be generated at such a project. 

“We believe that the lack of the ability to determine efficiency or generate proper forecasts impedes efforts to make the wave energy sector bankable.

“If the software that we develop, once fully verified, becomes widely accepted and agreed upon as a software that can correctly predict the wave energy generated, this will be a significant step forward for the whole sector towards bankability. This shall lower the risks of wrongly forecasting energy generation amounts in a certain site in question, which will in turn minimise the financial risk for the debt givers.”

Can real-time wave power data increase maintenance efficiency?

The company draws an important distinction between offshore, near-shore, and onshore wave power development. Onshore generators rely on waves rolling across shallow continental shelves close to land. As such, they see less extreme conditions than those in deeper, offshore waters.

Just as with offshore wind generation, costs increase as generation moves further from land. Operations and maintenance for offshore wave power requires ships, divers, and complicated procedures for standard activities.

Their technology uses land-based generators with floating arms deployed over the side of a pier. These rise and fall with waves, generating energy via hydraulic compression. This hardware will test the real-time monitoring software, but Eco Wave plans to make it usable for offshore installations using hydraulic compression.

Braverman said: “Even though our operations and maintenance procedures are easier, there is still a significant value in having an efficient control system with real-time data. The control system will basically collect info from a wave buoy – which is external to the power station – and show how much energy should be generated from data collected about wave height, frequency, and other factors. This takes into account preprogrammed losses of the energy conversion process.

“If the amount actually generated significantly differs from the amount forecasted by the software, then the power station operators will understand in real-time that there is a malfunction in the energy production process. They will be able to connect remotely in real-time to the software’s sub-systems, such as the hydraulics or electricals, and detect the subsystem where the malfunction has happened. Such real time detection will lead to decreased costs for maintenance, and production gains from detecting real time errors and fixing them as soon as possible.”

What else holds wave power back?

Cost is only one factor holding back wave power. The Strathclyde study emphasised “weaknesses in government and industrial strategy to support wave energy innovation”.

It continues: “We found an extremely complex wave energy innovation policy landscape, managed by numerous different funding agencies across three levels of government. This landscape has also been fast changing, with a succession of new schemes emerging, each with their own eligibility criteria and objectives.”

While this study only looked at development in one area, it matches Eco Wave Power’s experience. Braverman said: “I believe two main things will need to change, and the first is debt financing. This is key for wave energy commercialisation, the same as happened for wind and solar in the past.

“There is a need to faster adopt and implement regulatory frameworks, supportive policies, and relevant legal frameworks that will enable rapid implementation of wave energy projects around the world.

“In many cases we are approached by coastal cities, countries, and ports that are asking to enquire about the possibility of installing our wave energy power stations on their breakwaters. However, they sometimes find out that there is no legal framework or clear path for such implementation and grid connection. As a result, they commence a process of setting the policies, which might be timely and may delay projects execution.”

The Strathclyde report also noted the lack of cooperation and information exchange among developers. Examining projects in Scotland, it states: “Knowledge exchange was hindered by a lack of knowledge codification, meaning that knowledge generated from research, design, and development projects remained tacit and was limited to the experiences of their staff rather than the wider sector.”

In contrast, Braverman said that the company will test its software with its Israeli project, giving access to the resulting data to universities and researchers. After testing, Eco Wave Power will make the software available to third parties.