In Europe, electricity is generated in many different ways. Electricity is currently not easy to store, so demand and generation have to be managed so that they are always in balance. Some example types of electricity generation currently in mass use are:
In Europe we currently face a ´trilemma´ of objectives for the energy we produce. The key goals are for energy generation to be:
Generation sources should be able to meet demand today, and in the future. They should also not cause irreversible damage to the environment through the emission of carbon and pollutants.
Generation should be affordable and not make electricity bills too expensive for the consumer.
Generation should be predictable and able to meet consumer demand. A variety of different generation types means that shortages in fuel supply are not as big a problem.
Electricity generation is measured in kilowatt-hours (kWh). This is the amount of power produced over a period of time. To give some perspective boiling a kettle uses around 0.1kWh. The average house in Europe uses around 4500kWh per year.
Carbon dioxide production is measured in megatonnes of carbon dioxide per year (MtCO2). 1kWh of coal generation produces 0.94kg of CO2 emissions. European targets are to cut greenhouse gas emissions by at least 40% on 1990 levels by 2030.
There are various ways that electricity can be generated from the ocean resource. Examples of this are wave, tidal stream, tidal lagoon, ocean thermal energy conversion and salinity gradient. This site focuses on wave and tidal stream as the two main forms of ocean energy with the highest resource in Europe. Wave and tidal stream are new types of electricity generation technologies that have large potential but are not yet producing large amounts of electricity
There are two forms of tidal energy generation - tidal stream and tidal lagoon. This web page focuses on tidal stream.
The tides are caused by the gravitational pull of the moon as it orbits around the earth. The tide comes in and out approximately twice a day. A tidal stream moving fast enough for energy generation occurs at locations where water has to pass through a confined area, for example between two pieces of land or islands.
Tidal stream devices generate electricity by turning the kinetic energy caused by the tidal stream into electricity, usually by the turning of blades around a central axis in a tidal turbine.
Waves are caused by the movement of the wind on the surface of the ocean. Over long distances this effect can concentrate energy in large movements called ocean swells.
Wave energy is generated by converting the kinetic energy in the movement of the waves into electricity. This is done in many ways and there are multiple forms of wave energy converters. There is active research in novel devices for wave energy, with many options for solutions still to be investigated.
For further learning download our handout or play the game to see if you can use this information to power a set of islands!
The educational materials featured in these web pages have been created through the ETIP Ocean project, in collaboration with the EnFait and Marinet2 projects.