Donna McCabe (Discover Science & Engineering): You’re all very welcome here today, to the Science Gallery, for Science Week. We’re on, what day, four…five…six, Thursday, today. So we’re nearly at the end of the week of Science Week. Sheila and John Kirby are going to be giving a talk on behalf of Sustainable Energy Ireland today. And their talk is entitled “Energy: the challenges and opportunities”. So Sheila and John are both research students, as part of UCD’s Energy Needs Ireland (ENI) Group. So during the course of the presentation they are going to discuss climate change, renewable energy in Ireland today for the future. And other students from ENI are also going to join them at the top for the Q&A sessions afterwards. Make sure you have your questions ready for that. Don’t forget that you can get more information on Science careers at MyScienceCareer.ie and, of course, Science Week information at ScienceWeek.ie. So without further ado over to Sheila.
Sheila Nolan: Hey guys, how’s things? OK, I'm Sheila. I'm a third-year mechanical engineering student in UCD. I'm going to speak today about energy, the challenges and the opportunities available in the energy sector. Firstly, who are SEI? [Slide: "Who are SEI?"] SEI are Ireland’s National Energy Agency. They’re responsible for the promotion and assistance in the development of sustainable energy. They have programmes for all sectors – the business sector and for home owners. And SEI have education programmes for primary and secondary school students, like yourself. We’ve a video later on about the One Good Idea Project. OK, so who are ENI?
I was a part of this group who did research during the summer and we looked at Ireland’s energy future and we try to promote energy awareness amongst the public. We have a number of outputs which we have on our website. You can go onto that if you want to later on and have a look at some of our stuff. So where do you guys come in? How many of you do science? [Audience: show of hands] Really good, that’s cool. How many of you would want to do science in the future, or engineering? [Audience: show of hands] OK. Maybe after today you might consider science a bit more. You might want to do it in college. There are huge opportunities in the renewable energy sector for science and engineering graduates. And the government are putting huge amounts of money into this area. Engineering and science are really important for a number of reasons. Firstly, Ireland has EU targets to reach as regards energy and carbon emissions. And we need engineers and scientists to help us to meet these targets. Engineering and science are really important for our economy as well. If we have intelligent and highly-skilled engineers and scientists our economy will improve and develop, and we’ll be able to attract multinational companies to Ireland. You might be familiar with the Kyoto Agreement, which is an agreement to try to reduce carbon emissions and to try and stop global warming. However, the Kyoto Agreement is going to come to an end at the end of this year. So there’s plans to have a Copenhagen Treaty, which will promote further carbon dioxide reduction and try and help the global warming issue.
I am going to talk about fossil fuels. I’m sure you all know what fossil fuels are. I’ll go through them quickly. What are they? They’re non-renewable sources of energy. They are formed over millions of years from dead plants and animals. The animals die and the plants die and their remains are compressed under intense heat and pressure over millions of years, and they’re turned into fossil fuels. Fossil fuels can be burned and when they’re burned they react with the oxygen in the air to create carbon dioxide. The first fossil fuel we’re going to look at is coal. There’s about 100 years of coal left in the world. Coal is very carbon intensive, which means it gives out a lot of carbon dioxide when it’s burned. Gas, there’s about 40-50 years of gas left. Gas is a bit cleaner than coal. Not much cleaner, but it is cleaner. It doesn’t give out as much carbon dioxide when it’s burned. Peat is Ireland’s only indigenous source of fossil fuels. It’s very carbon intensive, which means it gives out a lot of carbon dioxide when it’s burned. Oil is very important. But we only have about 40 years of it left.
So what do we use fossil fuels for? For electricity generation – we burn the fossil fuels and we use the heat to create steam which turns turbines, which in turn generates electricity. In transport - for our planes, for our cars. We use it in heating our homes and our buildings. And we use it for creating things like plastics and chemicals used in medicine. But why are they harmful? They contain an element called carbon. And when this carbon burns it reacts with the oxygen in the air to produce carbon dioxide. Now this is the greenhouse effect. [Slide: Greenhouse Effect] I’m sure you all know what it is. Basically what happens is, the Sun’s energy comes through the atmosphere and it heats the Earth. Some of the energy gets caught in the atmosphere and this helps to keep a nice temperature around the world, which helps promote life. However, as more and more carbon dioxide is emitted into the atmosphere there is an enhanced greenhouse effect which is causing global warming. Some of the evidence of global warming – surface temperatures rise, which causes the ice caps to melt. As a result of this, sea levels can rise. If temperatures continue to rise we might have longer droughts, which has an effect on plants and animals, and can lead to starvation. There’s been evidence over the last few decades that storms and hurricanes are increasing in intensity, getting stronger. The wind speeds are getting stronger. We’re having more rain. They are all signs of global warming.
If global warming wasn’t a good enough reason to reduce our dependency, here are a few more reasons. [Slide: Fossil Fuels Dependence] Fossil fuel reserves are depleting. As I mentioned earlier, we only have about 100 years of coal left. We only have about 40 years of gas and oil. Added to this we have population growth. At the moment population is about 6 billion people. However, in the next 40 years it’s going to grow to about 9 billion. With growing population we have growing energy demand. We need more energy to heat the homes, to power our cars and to make electricity.
[Slide: Security of Supply Issues] Now this is a very important issue. It’s called the Security Supply Issue. If we’re getting fossil fuels from foreign countries they have to be imported. And if there’s a disruption to those imports we don’t have much energy. Here we can see Ireland on the left hand side of the photograph. [Slide: Main Gas Pipelines across Europe] And the red lines indicate the pipelines. These pipelines are importing gas from across Europe. Most of our gas will probably come from Russia. And if this is disrupted we won’t get any gas. We won’t be able to make electricity. At present Ireland uses about 98% fossil fuels for every piece of energy generated. This isn’t a great idea. We have very few indigenous sources in Ireland. So we need to import from other countries. As a result of this we are very vulnerable to changing fossil fuel prices. So what must Ireland do? We need to reduce our dependency on fossil fuels. We can do this by generating electricity from renewables and from low carbon alternatives. We need to improve energy efficiency in buildings. We can do this by insulating our homes, our attics, and by being more energy aware. We need to start diversifying transport from petrol and diesel. We might be able to use electric vehicles.
So what is Ireland doing? As I mentioned earlier, we have 2020 targets to meet. These are EU targets. We need to see if we can get electricity generation from renewables, about 40%. We need to reduce our carbon emissions by 20%. We need to increase energy efficiency in our homes. And we need to see if we can get more electric vehicles onto the roads. We need to upgrade our grid. The grid is the transmission for electricity. So it’s the pylons and the overhead cables. And we have plans to build an interconnector, which is just a big cable under the ocean, connecting Ireland to England. And this will enable us to import and export electricity. So I am going to hand over to John now. He’s going to speak about alternatives. [Applause]
John Kirby: Hello. My name is John Kirby. And I’m also an engineering student in UCD. I’m an electrical engineering student. And I was a member of Energy Needs Ireland as well. As Sheila mentioned to you, we need to get away from using fossil fuels. And we need to move to more cleaner and sustainable sources of energy. This involves changing every sector, from what powers our cars to what heats our homes and to what generates our electricity. If any of you do decide to go on and study science or engineering at third level you’ll have to get familiar with renewable energy and climate change, because it’s very important now. The first thing I’m going to talk about is electricity. I am not sure if you’re sure how electricity is produced. But basically there’s three criteria needed. You need a magnet, surrounded by a coil of wire and relative motion between the two. [Slide: Magnet, coil, motion and an electricity sign] And if these three criteria are met electricity will be produced in the wire. Wind energy next – wind energy will be very important in the next couple of years, because we’ve a target of 40% of our electricity generated from renewables. Much of this target will be met with wind energy. So you will see wind turbines around the country, and you’re going to see a lot more of them. Wind energy comes from the Sun. The Sun heats the Earth and it heats the surface at different ranges. What happens is, certain parts are heated more than others. And warm air will rise. And then the cold air will be sucked in and thus wind will be formed. This energy then can be used to turn turbines. The blades of the wind turbine will cause the motion, as I mentioned a couple of slides back. The motion which turns the magnet inside of the coil, this is caused with the turning of the blades. And so electricity then will be produced in the wire.
This map here is a map of Europe. [Slide: Map of Europe – Wind Speeds] And it shows the wind speeds. The purple and red zones are the areas of the highest wind speeds. And so you can see Ireland is absolutely ideally located to avail of this energy. One issue with wind is that the West of Ireland is the purple region. And so that’s the area where wind blows the strongest. The problem with that is that the main demand load centre for electricity in Ireland, the electricity is needed most in Dublin, which is on the east coast. And so transmission lines will need to be built across the country to transport the power from the wind turbines. Wind is now a mature technology, so it’s very important.
In this picture you can see the size of these blades. [Slide: Photo - Wind Turbine Blade] They really are enormous. And you can see the complicated engineering that would’ve had to go in to design this blade, to maximise its efficiency. Blades can be up to 80 metres in diameter. They really are huge. This is another diagram here. [Slide: Photo - Wind Turbine Tower] It’s the tower which supports the blades. And I’m not sure how familiar you are with them. But if you are close to a wind turbine, despite their size, they are really quiet. You’d hardly even hear them. I’m going to talk about ocean energy next. Ocean energy – you mightn’t be very familiar with it. Because it’s not something you’d see. But some really exciting development is taking place in ocean at the moment. 70% of the Earth’s surface is covered with ocean, and it’s a vast source of energy, and it’s largely untapped at the moment. There’s two ways of extracting the energy from the ocean. We can use the waves or we could use tidal. And once again Ireland is ideally located as it has the Atlantic Ocean to the West Coast. You can see here a map of the waves coming up towards Ireland. [Slide: Map - Wave Patterns Ireland] So wave energy - we have to harness the energy from the waves. It’s still in the development stages at the moment.
But there’s a couple of different devices out there that can achieve this. On the left here you have a Pelamis – this is called a sea snake. [Slide: Photo - Pelamis – Sea Snake] It’s a Pelamis device. And this uses the motion of the wave to extract energy and produce electricity. And over here this is a WaveBob device. [Slide: Photo - WaveBob Device] And this is a floating device. And this has a very clever mechanism. It’s able to use the bobbing motion to change it into electricity. You see over here now we have a small version of this, in the tank, it’s just a small scale model of how it works. [Demonstration: Small Scale Model]
Tidal energy uses the energy of tides coming in and tides going out. And it’s able to transform this energy into electricity. Tides then are a result of the Moon’s pull on the Earth. They are regular and predictable. So an advantage with tidal energy as opposed to wind energy or wave energy is that you pretty much know what kind of energy you’re going to get out of the tides, whereas with wave energy or wind energy, there’s going to be days when the seas are calm. There’s going to be days when the wind isn’t blowing. And so the energy from these sources is going to be very small. With tidal you can pretty much predict what you’re going to get from it. And it’s in development stages. It also shows the importance of having a good mix of generating technologies. You must generate electricity from a couple of different sources.
Now I’m going to talk about solar energy. And this is energy which comes directly from the Sun. Again it can be harnessed in two ways. On the left here, these are solar panels which are used to heat water. [Slide: Photo - solar panels] And of the solar panels that you’ll see around Ireland on houses, the majority of them will be this type. So this type contains tubes with fluid in them. And the Sun heats the fluid in these tubes. And these are transported then, the fluid is moved to the point of use. And it can be used to heat water. The other type is photovoltaic solar panels. And these are of limited use in Ireland due to the lack of sunshine. But they can generate electricity directly from the Sun. Ireland does have a better solar energy resource than is realised. Much of our hot water needs could be met with solar. Even on a cloudy day, enough sun will pass through the clouds to be able to heat the water.
Now I’m going to talk about hydro energy. Hydro energy uses the potential energy of water. The main hydro-electric power plant in Ireland is in Ardnacrusha in County Clare. And this has a purpose-built canal feeding onto the River Shannon. It was built in 1929, and back then it could power the whole of Ireland’s energy… Ireland’s electricity needs, just this power plant. This then is Turlough Hill in County Wicklow. [Slide: Photo - Turlough Hill Power Station] What you have here is, you have two reservoirs, an upper and a lower reservoir. And this is an example of electricity storage. Because during the day when demand is high for electricity, (when) people need electricity, there’s a hidden turbine underneath this upper dam, upper lake of water. And this water then is allowed flow through the turbine, produce electricity, and flow down into the lower lake. And at night time then when most people are asleep in bed and there’s very little need for electricity, this water can be pumped back up to the upper reservoir. So just basically to go through the generation of electricity from this way, the water starts off with high potential energy. It then changes to kinetic energy, flows down and passes through a turbine and is producing electricity. So it’s changed to electric energy. And electric energy is the most useful form of energy we have.
Now I’m going to talk about geothermal energy. Geothermal energy is energy stored in the Earth. There’s two sources of this. There’s the source of the Sun. So the Sun can be used to heat the Earth’s crust. And the Earth’s crust acts as insulator. You can see here, this can be used for domestic heating. [Slide: Geothermal Energy – Domestic Heating] So what you need to do is, you need to build pipes down underneath the ground. They could go down to depths of maybe 100 metres. And you’ve a heat pump which transports this heat that’s already in the ground into your home. For the amount of electricity you put in you get much more heat out. There’s also grants available from SEI for home owners who wish to do this. Geothermal heat can also be used for electricity production, but you need to drill down to much lower depths. You must go down to maybe three kilometres below the surface to access this. And this is using the energy of the Earth’s core. Temperatures exceeding the temperatures on the surface of the Sun are found at this depth. And then what happens is, the heat is used to create steam and the steam will turn turbines and produce electricity.
[Slide: What is Bio-energy?] Bio-energy is energy stored in plant and other biological material. Plants go through a process known as photosynthesis. What happens is, they use sunlight and carbon dioxide to produce energy. This energy then can be burned. These plants can be burned and energy will be released for our use. Alternatively plants can be processed and used to derive biofuels, and these can be used for transport. So the oil is got from the plant and they can be used in aviation or to power cars maybe in the future. One of the issues with bio-energy is that you require a lot of land to grow enough crops to produce a suitable amount of energy. A lot of research is going on at the moment to develop genetically modified crops. I’m not sure if you heard of it. But what happens is, it changes the DNA of the crops to allow them to produce a much greater yield. And if this is successful and is allowed to be implemented in Ireland it could be a possible source of energy in the future.
I’m going to finally finish up with nuclear energy. Nuclear energy uses stored potential energy in atoms. When you think of nuclear energy, everyone will probably think of the Chernobyl disaster. But the probability of that happening today is much less, is practically… it’s not going to happen because modern day power plants are much safer and they use fission reaction.
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