 So, there's actually been lots of studies where people have looked at how would Australia go to 100% renewable electricity. And every one of them says it's possible. The challenge we have is that every one of them assumes something that's not quite ready. It might be that we need a hydrogen economy, we need hot drive rocks, we need concentrated solar thermal. But what if we don't want to wait? Wind and solar are today ready for that sort of scale. In Australia, it is cheaper to put in new wind and new PV than to put in a new fossil generator. The challenge is that these are now variable resources. We get lots of energy if the sun is shining and the wind is blowing, but if there's a shortage, then suddenly we're in trouble. So storage is the key to enabling this. We use something to store the energy when we have an excess, and then we have an opportunity to get that energy back when there's a shortage. Batteries are great at a household level. They do a really good job there, but they're much too expensive to be doing large-scale energy storage. So what are the options there? The solution we're looking to is pumped hydro energy storage, which is actually 95% of energy storage around the world. The concept is really simple. We basically have two reservoirs, one slightly higher than the other one. We pump water up the hill when we have an excess of energy, and then when we have a shortage, we let the water run back down the hill, and then we get the power back at a later time with a little bit of loss. Now ironically, these pumped hydro systems were developed for the fossil fuel in the nuclear power industries. These big power stations just love to run along at a flat out 100%, but our demand varies during the day when things go up and then at night they drop down. So we use storage to balance that out. Things are a little bit different when we start to look at renewables. What we're doing there is instead we're trying to balance out the generation. When we have lots of sunshine or lots of wind blowing, then we can use storage, pumped hydro storage, by pumping the water up the hill to balance out that variation that we have in the generation. The challenge when we start to talk about doing pumped hydro storage in Australia is Australia is hot, Australia is dry, Australia is flat. All our big rivers, we've already downed for hydro systems, and as a result of that we've actually got a pretty tough environmental situation where all these big rivers have completely had their flows disrupted. So what we've done is instead of looking to the valleys, is we're now looking to the hilltops, we're looking for off-river solutions. This suddenly opens up a much bigger area of Australia, and it has a second advantage is that that reservoir that we're talking about is now much, much higher. And so we can store much more energy for the same size reservoir as we had before. And this is a sort of example of what we're talking about. So this is a system that's being developed in the high desert of the USA. What we have there is we have an upper reservoir, which is sitting on a plateau 300 metres above the plains below, and then we simply connect a pipe or a tunnel between the two, and we cycle the water between those two reservoirs. Not a river in sight. So what we're doing then is finding out where can we do this in Australia. So the starting point is we need to find places where we've got a nice high place, close to a low place. We don't want them too far apart because the pipes will be too expensive. We need them reasonably close together. But we find there are lots of places. And in fact, if you have a look at the white dot on the screen, that's the area of reservoir that we need to use to balance 100% renewables for Australia. So the next thing we do is we then zoom in a bit closer. We start to hunt with our GIS algorithms for where can we put reservoirs in the landscape. And this is an example here where we're finding reservoirs, minimum size, around about 10 hectares. And that's then enough energy for 40,000 homes for about a day. The advantage of going off river is we don't need to build dams like this anymore. We're not trying to block the river. We don't have to deal with earthquakes. We don't have to deal with a once-in-a-thousand-year flood. And we don't have to deal with all the environmental challenges of blocking the river. So that problem with Australia's dryness, it's no longer there. It's in fact the ultimate in recycling. What we're doing is simply hundreds of times a year, we're pumping water to the top, and let it come back down again. Up and down, up and down. We're not trying to block the rivers. We're just trying to catch the rainfall that sits on them to replace the evaporation. So what does that mean in terms of an Australian context now? The conversations that we've been having around pumped hydro have started to change the thinking in Australia. In fact, the Prime Minister, when he had his opening address for the year discussing the policy landscape, said, energy storage, long neglected in Australia, is going to be a focus. And particularly, that pumped hydro was going to be an important part of that energy mix. Suddenly, older band and mine sites, seawater sites, and off river sites are on the table for new projects. So energy storage has rapidly been recognised in Australia as a key enabler of high renewable energy penetration, which has helped Australia start to move further down the pathway to 100% renewables. One of the things we recognise there is that sometimes in order to solve the problems of the future, we need to look to the solutions from the past.