Energy Around Wales
Wales – An Alternative Future
It doesn’t take a genius to realise that we cannot keep on getting our energy by burning fossil fuels. We get most of our electricity by burning coal and natural gas in thermal power stations. And most of our transport is powered by burning petrol or diesel which is made from oil. Particularly oils and gas are running out and as supplies go down and demand from a developing world goes up prices get too expensive. Fossil fuels also cause environmental problems such as climate change and acid rain.
Thermal Power Stations in Wales
However there are alternative energy sources and in Wales we are blessed with some of the best geography for switching to these and as well as providing all of our own energy requirements we can even make a fortune by selling it to others who are not so blessed.
Tidal Power
For its area, Wales has a huge length of coastline and some of the biggest and most powerful tides in the world. Tides can be accurately predicted so are a very reliable source of alternative energy. One of the biggest tidal energy resources in the world is the Severn Estuary in South Wales. It is estimated that a large barrage could provide 5% of the UK’s electricity – Wales has 5% of the UK’s population! However it has problems; it would probably cost over £25 billion to build, it would destroy most of the existing estuary habitat and if it were to use the same technology as other barrages it would only generate power when water levels on the seaward side were significantly lower than the water levels on the landward side.
The proposed Severn barrage
New technology however would be to build tidal lagoons – Friends of The Earth Cymru have carried out studies that show that if triple lagoons were built over 25% of the estuary area that these would generate a similar amount of energy as the proposed barrage. Water moves by gravity either between different lagoons or the lagoons and the outside estuary. By doing this they make less electricity but they do it continuously – 24 hours a day – an alternative energy source that is totally reliable and what more it would be a lot cheaper than building a barrage.
Around our coastline we could also place smaller tidal generators such as these from Lunar Energy which would make electricity for over 20 hours per day. By placing the generators in different locations around our coast they would produce electricity at different times ensuring reliable supply. There are also a number of locations such as the Skerries off Anglesey and ‘The Bitches’ off West Wales that could produce energy from the SeaGen tidal stream generators. So Wales could become electricity self-sufficient just by using tidal power.
Waves could also provide large amounts of power – try to search for information on PELAMIS, LIMPET or Voith Generators. At the moment PELAMIS technology is the leader in harnessing wave power.
Tides
At the coast the sea seems to come in and go out twice a day. This huge movement of water is caused by the gravitational pull of the moon and to a lesser extent the sun. The water is pulled by the gravity of these two heavenly bodies creating areas of higher and lower sea levels within the seas and oceans. Combine this with the spinning of the earth and we end up with waves several metres high and sometimes hundreds of kilometres long rotating around ocean and sea basins such as the Atlantic Ocean or Irish Sea. The trough of the wave is low tide and the crest is high tide as the crest approaches a section of coast the tide comes in and after it passes the tide goes out. It usually takes around six hours to come in and six hours to go out so that there are two tides each day. However the tides are later each day by just under an hour so the times of low and high tide change.
Wales also has massive potential for wind power generation. Wales is in a zone of the world that experiences a lot of wind and in that zone there are two environments that get more than their fair share – West facing coasts and mountains. Wales is pretty much made up of most of these so with the exception of Scotland, Wales has the highest wind potential in Europe! Developments so far have been mainly on the mountains and moorlands but increasingly they are offshore. Wales again has the potential to easily provide all of our power but what happens if the wind doesn’t blow? Check out ‘Science in the News’ to see how electricity can be stored.
Biofuels
Anything that was recently alive could be used as a biofuel; wood is an obvious source. Because when they were growing, living things take CO2 out of the air (either directly as green plants or indirectly when plants or animals are eaten) it is only put back either as Methane when it rots or as Co2 if it is burned. Because there is no increase in the Co2 levels these fuels are called often called carbon neutral. Wales has a lot of forestry and the waste products such as branches and roots can be dried out and used in power stations instead of coal. There are several Energy-from-Waste projects including one in Cardiff and another near Merthyr Tydfil – these are mostly carbon neutral as long as recyclable materials such plastics made from oil are not burned.
The growth area however in the future will be biogas; anaerobic digesters can turn any organic material such as waste food, agricultural waste and even human sewage into useful biogas that can be used to generate electricity instead of natural gas or can even be used in our homes. It can even be liquified so that LPG powered cars can use it as a fuel – several water companies in England are powering their vehicles with gas from human sewage – a poo powered car?
Fuel crops which take up land that could be used for food are unpopular in a world where millions go hungry each day but both biodiesel and bioethanol (which replaces petrol) can be made from things like sugar cane or sunflower oil.
Hydro Electric Power - H.E.P.
All that is needed to make water from flowing water is fast flowing rivers in steep valleys; or in other words – Rain and mountains = Wales. Again the mountains of South, Mid and especially North Wales have huge potential to develop H.E.P. In an energy environment dominated by renewables H.E.P. is essential as it acts as an electricity store which can be switched on at the flick of a switch. Pumped storage is used to actually use spare electricity from things such as wind farms to pump water up mountains so that it can be used when it is needed. Dinorwig in North Wales is one of the best examples of this but a lot of people object to having our beautiful Welsh landscapes flooded by reservoirs.
Solar Power
You might think that we don’t get enough sun in Wales to use solar power but the latest technology can make electricity directly from photovoltaic cells or heat water to a scorching 70 degrees even on a Welsh roof on an overcast day in Winter.
This £13.4 million solar panel farm, is now up and running in Monmouthshire. The solar farm, consisting of 22,500 panels, was built on a 32-acre site across four fields at Llancayo, near Usk. The farm will generate enough electricity to power 2,500 homes, 24 hours a day, seven days a week. It will save at least 60,000 tonnes of CO2 emissions over 25 years compared to fossil fuels.
So what will we be powering us in the future?
We will hopefully be moving to a low carbon economy here in Wales and be exporting all of that lovely clean electricity to our neighbours and earning a lot of money – no wonder the Welsh Government has requested that energy supply decisions become a devolved issue from Westminster. Wales is poised to become a major green energy supplier even without the proposed new nuclear power plant proposed for Wylfa on Anglesey.
Find out what you have learned in this edition by taking our energy quiz.
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Activity
Write a letter to the Welsh Government explaining your views on energy supply in Wales. Use the following sheet to help you structure your letter.
