As of today, tidal installed power could only provide the enough energy to power 400 000 homes. In this story, we will cover how tidal power works and why it isn't everywhere yet.

Tides are the rise and fall of sea levels caused by the combined gravitational forces exerted by the Moon, the Sun and the rotation of the Earth. Tidal energy takes advantage of this phenomenon to produce electricity and it is one of the oldest ways of harvesting energy from nature. Many 

 have been found on the European Atlantic coast dating from the Middle Ages or even from Roman times.

The principles of operation are very simple, just the flow of the water drives the turbine, which moves a gearbox, and then a generator produces the electricity.

There are two main ways to extract power:

It takes advantage of the streams created by the tides; this type of energy production is more similar to wind turbines.

They are the most common among the tidal stream turbines; they are very similar to wind turbines and usually set up in clusters in underwater 

The turbine is tethered to the sea floor while operating, but the turbines remain close to the surface, so the undersea work is cheaper and can be moved to 

Tidal kites force water through a turbine installed at the front while it "flies" through the sea. The first trials of this technology are currently underway.

It takes advantage of the difference between the high and the low tide. This works by building a dam across a region where the seawater meets the land, which magnifies the difference between the low and high tide. This type of power plant produces 98% of all tidal energy globally.

First, the dam doors are shut until the sea reaches its maximum level. At that moment, the doors are open, and the water flows into the basin. Built inside this dam are several turbines harvesting the energy of the flowing water.

Then the dam is closed, and the water accumulates in the basin.

Once the sea is at its minimum level, the dam's gates are open again, and the turbine generator can produce electricity.

As the tides rise and fall naturally, no fuel is required, so it is truly renewable, and, unlike other renewable energy sources, it is entirely predictable. There are always two high and two low periods of low tides every day so that tidal power plants 

can generate power for up to 14 every 24 hours

 every day of the year. As waves are well-studied, their height and time can be predicted years in advance with high accuracy.

Moreover, tidal energy systems are inherently age resistant and have long lifespans. The average estimate for most tidal systems is 

 of working use. To put into perspective, a solar panel usually degrades after an average of 25–30 years. 

 are also needed; tidal turbines can be smaller because water is denser than air thus, exerts a more significant force on the blades of the turbine.

The tidal industry is young; for that reason, manufacturing and supply chains have to be yet developed, making these projects very expensive.

 such as corrosion or building big structures and maintaining them in turbulent seas; and this is not cheap at all. Other renewable resource solutions have more affordable upfront costs. Tidal energy systems have long lifespans and eventually pay themselves off, but governments and companies are more concerned with their 5-year budget rather than a 60-year projection.

; to operate effectively and efficiently, they require a particular set of characteristics. About 25% of all the potential space in which tidal turbines can be installed is in Scotland.

Hopefully, the Swansea Bay Tidal Lagoon project in the UK, and MeyGen Tidal energy in Scotland, will encourage more investors and companies to look for new solutions to the energy and environmental problems we need to solve.

And what do you think, will we see tidal energy becoming more popular? Do you think it is really useful in this type of technology?.

Future Thought Leaders is a democratic space presenting the thoughts and opinions of rising Sustainability & Energy writers, their opinions do not necessarily represent those of illuminem.

Why isn't tidal energy a huge thing right now?

Let's start with what biogas is and how it is produced.


Biogas is a fuel generated in natural environments or specific devices, by the biodegradation reactions of organic matter, through the action of micro-organisms and other factors, in the absence of oxygen (i.e. in an anaerobic environment). We get biomethane if we put this biogas through a scrubbing process to decrease the amount of CO2 and increase the methane concentration.

As we can see, a wide range of feedstocks can be used to produce biogas, biomethane, and various processes. The choice of feedstock and the process will change the properties of the gas we end.

Biogas has very similar characteristics to natural gas, so it can be transported using existing infrastructure once produced.

According to data from BP and the IEA — International Energy Agency —, only about 

2% of the 2700 TWh of the total energy produced in Europe

 could come from biogas with the current infrastructure.

Below we will cover the advantages and disadvantages of biogas compared to other energy sources.

. More investment in R&D is needed for biogas to be competitive against natural gas. In addition, biogas plants' productivity depends on the operator's experience and skilled staff to carry out maintenance work properly.

Currently, there are a low number of companies specialising in this technology, and experienced professionals, making adopting biogas more difficult.

The price of biogas energy is higher than other renewable energy sources. It is, therefore, not usually an attractive investment for companies that prefer to install solar panels on their land.

It is, therefore, not usually an attractive investment for companies that prefer to install solar panels on their land, which also tends to have more significant institutional incentives (tax rebates, subsidies, etc.),

Biomethane, in particular, is also more expensive than its non-green equivalent, natural gas.

Because usually, the rural areas, i.e. the areas where the feedstock that would allow us to produce the biogas is located, are far from the areas of consumption, the urban areas. Therefore investment in infrastructure would be necessary.

For example, I will show you a picture of the land use distribution in my country, Spain. As the red areas — urban areas — are far away from the rural areas, the infrastructure in rural areas is usually not very good.

Biomethane provides a more reliable energy source than other renewable energies, such as solar or wind. In addition, its impact on the environment is minimal. Biomethane can reduce emissions 

Biomethane power plants can achieve emissions of 

, while lignite plants release more than 

Furthermore, let's consider that we have used organic material to produce it, which would otherwise have been wasted or had to be processed. We obtain a negative carbon footprint, i.e. we capture CO2 from the environment.

It is a form of domestic energy that does not need to be imported from other countries because they all generate waste.

Energy is a vital resource for the economy and, therefore, strategic. Today — the year 2022 — diplomatic relations between countries are very fragile, and having an energy model based on imports can be dangerous, as we have already seen.

Waste products from agriculture and livestock farming are available all year round. Currently, these wastes are, at best, disposed of in landfills, but they can also end up in illegal landfills and lead to soil or groundwater contamination.

As well as being suitable for the environment, it would also be good for the farmer's or rancher's pocket, who could earn a little extra income by selling the waste they would previously have thrown away.

And you may ask, but now and not before if it is a renewable energy source, why has it not been developed as much as wind or solar photovoltaic?

And the answer is quite simple, because of the 

, the methane obtained from biogas was much more expensive than natural gas, which was at a ridiculous price until 2021.


Russia's restriction of gas supplies has caused gas prices in Europe to skyrocket, 

making the investment in biogas very profitable

The European Union has realised what good alternative biogas can be to natural gas and has included it in a report developed by the IEA entitled 

“A 10-Point Plan to Reduce the European Union’s Reliance on Russian Natural Gas”.

And what do you think, will we see biogas booming with the current situation in Europe? Do you think it can make good synergies with other renewable energy sources?

Organic waste has enormous potential in Europe

Pablo Moral Vega is a last year BSc student in mechanical engineering at 

 working on the optimisation of industrial process flows applying lean manufacturing and six sigma techniques. Investor and enthusiast of the energy and mining sector. Coffee lover.

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Pablo Moral Vega

Pablo Moral Vega

Organic waste has enormous potential in Europe

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