Wave vs tidal energy: new developments in hydropower
With the ever-growing political pressure to develop renewable energy solutions across the globe, making use of the ocean’s potential for energy production is a necessity.
It is not surprising that Inna Braverman, co-founder of Eco Wave Power (the first commercial-scale wave energy array in Europe), is a Slush headliner, and has been listed as one of the 100 most influential individuals by Medium.
Currently, all ocean energy tech, perhaps except for tidal range, is at an early stage of development. The first commercial projects develop rapidly which means that the worldwide competition for market leadership is open.
Nevertheless, the opportunity is there. For example, the US receive 2,100 terawatt-hours of incident wave energy along its coastlines each year, and tapping just one quarter of this potential could produce as much energy as the entire US hydropower system.
The potential of both wave and tidal energy is enormous. More reliable than many of their renewable energy counterparts, wave and tidal energy are more efficient and have longer lifespans. The unpredictability of other resources such as wind and solar power, has always been one of the major drawbacks of renewables and, much like them, wave and tidal energy are variable in nature. However, their patterns are less unpredictable than many other renewable energy sources.
For tidal currents, variability is very high on an hourly basis but limited for longer time spans (e.g. monthly, yearly variation). On the contrary, variability of ocean wave energy is relatively low for short time spans (hours) but can be great for longer periods of time — for example on a seasonal or annual basis.
Waves are produced by winds blowing across the surface of the ocean. However, because waves travel across the ocean, their arrival time at the wave power facility may be more predictable than the wind’s. In contrast, tidal energy, which is driven by the gravitational pull of the moon and sun, is periodic and allows for the resource forecasts with a high reliability over long time spans and predictable even years in advance.
The worldwide potential for wave and tidal power is enormous, local geography greatly influences the electricity generation potential of each technology. Wave energy resources are best between 30º and 60º latitude in both hemispheres, and the potential tends to be better on western coast which limits their availability on a global scale.
Obstacles
According to researchers, technological barriers represent the most important issue that the ocean energy sector faces. Cost is also an issue to be taken into account. Like most emerging energy technologies, wave and tidal tech are currently more expensive than traditional energy generating resources, especially in developing countries.
Until now, there have been serious gaps concerning the scientific evidence on the environmental effects of ocean energy technologies that need to be remedied. Existing data is still very much dispersed amongst countries, researchers and industrial developers.
The main expected environmental impacts of the ocean wave and tidal tech include impact on the benthic community (due to alterations in flow patterns, wave structures, sediment dynamics), species-specific response to habitat change, and the entanglement of marine mammals, turtles, larger fish and seabirds. Socio-economic impacts on both the local populations and society as a whole also need to be considered.
Only then will we be able to fully understand the potential of this new tech and harness ocean’s energy in a profitable, sustainable and efficient ways. Considering the ever-increasing number of registered companies in this sector globally, this could be happening very soon.
Authored by: Marguerite Bellec, Startup Scout, CUBE
Edited by: Emily McDonnell, Global Head of Community, CUBE
CUBE is a global innovation ecosystem that acts as the strategic liaison between deep-tech startups and corporates who are determined to shape the future of industry 4.0.
