Australia’s Energy Security – 24/7 Concentrated Solar Thermal Power plus Molten Salt Storage (CSP )
00:00:04
Problem with renewable energy is the lack of continuous supply solar power only when it’s sunny wind power only when it’s windy and wave / when the sea is not too rough and Russell Bearden have come to South Spain to visit Gemma solar the first solar tower power station that can produce electricity 24 hours a day in order to get a real sense of the scale of this place I need to get a little bit higher some well a little bit but it’s incredible and I can’t believe I’m flying this plane some just fought at the tower up ahead
so he said just pointed at our and carry on okay here is Gemma Sola you can see it just the lowest no thousands of these heliostat these revolving burrows it’s just amazing feels like we’re looking into the future photovoltaic is like one of the fastest-growing energy sources in the world at the moment but these aren’t photovoltaics are they yeah but photonics at all so these are just as glass are mirrors and they are reflecting the light on top of the tower the reflected sunlight from the 2650 heliostats combined can generate enough electricity to power 25,000 homes
but only if they’re all pointing in exactly the right spot Santiago’s brought along one of these miniature parabolic mirrors which I guess is almost like a perfect scale model of obviousl Litella yes I mean the tower looks like in the middle of a circle failure stats on every other stat is like yeah taking a different angle to reflect the light on top of the tower and then to concentrate all the energy on on a single spot so let me try let me try let go yeah that’s great it’s going oh wow you can see it Catching Fire it’s
so sensitive like one tiny degree out and it stops burning I mean this must be the challenge that you’re facing exactly I mean exactly what we have to be doing I mean we have to be very precise in moving the image that’s in the right position to concentrate the light there sunlight is reflected from each heliostat onto a central receiver at the top of the tower sodium and potassium nitrate salts are pumped from the cold salts tank up to the receiver where they absorb the concentrated solar thermal energy reaching temperatures of up to five hundred and sixty-five degrees the heated salt so then pumped down to the hot salts tank where they can be stored in a molten state or used to generate electricity via the heat engine this is the hot molten salt tank that contains the molten salts at five hundred and sixty-five degrees this is like a big battery
but is a thermal battery is not an electrical battery in fact the energy which is accumulative here is enough to continue operating the turbine for fifteen hours at full speed so this is what distinguishes this place from other solar tower the generators around the world it’s actually that storage exactly being able to store energy this way means the solar power can for the first time be provided 24 hours a day not just when the sun shining this is the vessel in which the world became 16 it’s how you have war but maybe 500 degrees centigrade and already a hundred partial pressure this is incredible
so Santiago’s telling us is despite how futuristic this all looks the actual business end where they create the electricity is much the same as any other and coal-fired or even nuclear power plant the seat is a steam driven power play Wow this is what I’m thank you technologies around we are going to be reducing our cost but also due to the fact that the oil prices are going up will make it impossible to burn gas to produce electricity and then our plans will continue to be delivering cheap and clean energy to our children let’s say The problem with renewable energy is the lack of continuous supply: solar power only when it’s sunny, wind power only when it’s windy and wave power when the sea’s not too rough. I’m Russell Beard and I’ve come to the south of Spain to visit Gemasolar, the first solar power-tower station that can produce electricity 24 hours a day
but in order to get a real sense of the scale of this place I need to get a little bit higher My heart is in my mouth a little bit but it’s incredible and I can’t believe I’m flying this plane.
00:00:36
Sam just spotted the tower up ahead so he said just point at the tower and carry on.
00:00:41
OK here’s Gemasolar. You can see it just below us now. Thousands of these heliostats, these revolving mirrors.
00:00:50
It’s just amazing. It feels like we’re looking into the future.
00:00:55
Photovoltaics are one of the fastest-growing energy sources in the world at the moment but these aren’t photovoltaics, are they? No, not at all. They are not photovoltaics at all. They are just glass. They are mirrors and they are reflecting the light to the top of the tower.
00:01:11
The reflected sunlight from the 2,650 heliostats combined can generate enough electricity to power 25,000 homes but only if they’re pointing in exactly the right spot Santiago has brought along one of these miniature parabolic mirrors which I guess is almost like a perfect scale model of your solar tower.
00:01:31
Yes. I mean the tower is in the middle of a circle of heliostats and every heliostat is taking a different angle to reflect the light on top of the tower and then to concentrate all the energy on a single spot. So let me try.
00:01:49
Oh wow! You can see it catching fire. It’s so sensitive. Like one tiny degree out and it stops burning.
00:01:57
I mean this must be the challenge that you’re facing.
00:02:01
Exactly. Exactly what we have to be doing. We have to be very precise in moving the heliostats into the right position to concentrate the light there.
00:02:10
Sunlight is reflected from each heliostat to the central receiver at the top of the tower. Sodium and potassium nitrate salts are pumped from the cold salts tank up to the receiver where they absorb the concentrated solar thermal energy reaching temperatures of up to 565 degrees C.
00:02:28
The heated salts are then pumped into the hot salts tank where they can be stored in a molten state or used to generate electricity via the heat engine. This is the hot molten salt tank that contains the molten salts at 565 degrees C. This is like a big battery but it is a thermal battery it is not an electrical battery. In fact, the energy that is accumulated here is enough to continue operating the turbine for 15 hours at full speed.
00:03:00
So this is what distinguishes this from other solar towers around the world.
00:03:04
It is actually that storage.
00:03:08
Exactly. To store energy this way means that solar power can for the first time be provided 24 hours a day not just when the sun’s shining. This is the vessel in which the water turns to steam. In fact, you have water at maybe 500 degrees C at already 100 bars of pressure. This is incredible. So what Santiago’s telling is despite how futuristic this all looks the actual business end where they create the electricity is much the same as any other coal-fired or even nuclear power plant. It’s a steam-driven power plant.
00:03:47
Wow! Wow! This is what I’m talking about. Now this looks like a power station. And it is.
00:03:51
This technology’s been around for hundreds of years. So really out there is the only sci-fi part of this building. By the time the power comes down from the molten salt we’re talking about good old-fashioned steam turbines. That’s what we can hear now coming out of those chimneys at the top.
00:04:14
We are going to be reducing our costs but also due to oil prices going up it will make it impossible to burn gas to produce electricity and then our plant will continue to be delivering cheap and clean energy to our children, let’s say.
