Page last updated on 16th March 2026
How does tidal energy work and how could it impact your energy use?
One source of renewable energy is electricity from tides, also known as tidal electricity generation. Tidal energy currently makes up less than 0.01% of energy generation in the UK.
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This guide will take a closer look at tidal energy, answering questions like how does tidal energy work and how electricity from tidal energy can be generated.
What is tidal energy?
Tidal energy, also known as tidal electricity production, is a form of renewable energy that harnesses the movement of the ocean tides to generate electricity.
Sometimes, tidal energy is described as a form of hydropower. Hydropower typically relies on rivers and reservoirs to drive turbines, but tidal energy draws on electricity from tides and sea levels. Now, let’s take a closer look at how tidal power works.
How does tidal and wave energy work?
Every day, coastal areas experience high and low tides. The movement between high and low tides can be used to produce renewable energy. Tidal energy uses something called a ‘tidal barrage’, which contains turbines.
Here is a breakdown of the process:
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Tidal barrage
A tidal barrage is set up over a river estuary, or between two parts of land. Essentially, where the flow of water is the strongest.
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Water flows
As the water flow increases, and passes through the tidal barrage, the turbines are moved faster.
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Conversion of energy
As the turbines move, the energy from movement is converted into electricity that is transported back to land via undersea cables.
Most importantly, tidal power production depends on how strong the water flow is. To make this work well, tidal barrages need to be built in places where the water flows quickly. The faster the water flows, the more electricity from tides can be produced.
Advantages and disadvantages of tidal energy
If you want to learn more about tidal power production, we’ve put together a list of advantages and disadvantages.
Advantages of using electricity from tidal energy:
Reliability
Electricity from tides is a consistent renewable energy source. Because the nature of tides is predictable, tidal electricity generation produces approximately the same amount of electricity every month. In comparison, solar energy can be very weather dependent.
Low operating costs
While setting up the tidal power production plant can be expensive, the actual maintenance cost of the tidal electricity generation system is quite low.
Clean and renewable
As mentioned above, electricity from tidal energy is renewable. It also does not use fossil fuels, meaning that generating tidal energy does not create greenhouse gas emissions.
Challenges of using electricity from tidal energy
Geographic limits
While tidal power production can generate a lot of electricity, it needs to be set up in an area with strong and consistent tides. This means that tidal power plants can only be set up in a limited number of locations.
Environmental impact
Tidal barrages can potentially harm local ecosystems by disrupting fish migration and other aquatic life.
High initial costs
Building tidal electricity generation systems is expensive. For large-scale projects, the cost can be as high as £8.5–10 billion.
Renewable energy and smart meters
If you’re interested in Great Britain’s energy infrastructure, why not learn more about smart meters? Smart meters help to make the energy system smarter by allowing energy suppliers to offer incentives for households who can reduce their energy use during peak hours. This can help to balance supply and demand in the energy system.
If you're interested in different sources of renewable energy, take a look at our guides below.
Find out more:
How do solar panels work?
What are wind farms: all about wind energy
Biomass energy: definition, pros, cons and energy savings
What is hydropower and how does it work?
Learn more about how smart meters can help the environment.
What is global warming and what can I do about it?
Benefits of smart meters for Great Britain and the environment
Benefits of smart meters for customers.