We're installing technology now that's allowing us to capture the energy or the excess energy that would normally be sent out onto the grid. And we're harnessing that energy and putting it into devices like hot water systems. So a hot water system now is really a cheap form of the battery. Here we are in Wahroonga. We've installed a 10-kilowatt solar system recently with a 9.3-kilowatt-hour LG Chem battery. And we've got an electric hot water control device. So what we've got is we've got a backup inverter, this controls the house. If the power goes out on the grid, the backup allows the battery to feed energy into the house. So they may be the only house with the lights on in the street, lucky them. And up here we've got an electric hot water control device. And what that does is that directs the surplus energy that would normally be put out onto the grid receiving very little remuneration for, and we're diverting that energy into the two electric hot water heaters that they've got in the house, in effect making both of those hot water tanks a battery, and probably the cheapest battery you'll ever get.

So now we've got technology available that will allow the actual electricity that's being generated from the solar system, to heat the hot water in your house. Storing energy in a battery is one form of storing energy. Another form of storing energy is storing it in water. And in a hot water tank, there's a whole bunch of energy. So if we can use the solar energy from the roof and direct that into the hot water tanks, we've got in effect a battery, just that it's stored in water and not in lithium. So we've got technology available now that we can harness the sun's energy and put it directly into heating your hot water system electrically, which means you don't have to have solar hot water panels on the roof. We're doing it all from the solar power system. We can set up the hot water system, purely energised by the sun.