If you’ve ever been dumped by a big wave at Bells Beach, Bondi, Kirra or Margaret river you’ll understand the power of water. The power of the water isn’t just about getting dumped and eating sand. We’ve been using moving water to get us around in boats (and on surfboards) for quite some time.
More recently in human history we’ve been using running water to power mills for grinding things like seeds and grains. And even more recently than that we’ve been using the power of water to make electricity.
The Snowy Mountain Scheme in New South Wales is a hydroelectric scheme that’s been going for more than 35 years, and has been operating as the largest renewable energy generator in Australia, providing up to 3.5% of the mainland grid’s power.
A dam of the Snowy Hydroelectric Scheme. Visit their website.
The idea of hydroelectricity schemes like the Snowy Mountains Scheme is that power is produced through the gravitational force of falling or flowing water. It is one of the cleanest forms of energy around. The bad news is that in some places, constructing the dams and diverting the rivers to get the most amount of water possible to produce the highest possible amount of electricity can lead to environmental damage, both through construction but also through reduced water flows to the environment.
In some countries, building hydroelectric schemes means building dams so big that people have to be moved. Not just people, but whole villages. This is not so cool.
Already 20% of the world’s power is produced by hydropower. Constructing dams to make hydroelectricity is not the only way to harness the power of the water. There are other sorts of hydropower.
Sometimes called tidal energy, this is a form of hydropower that converts the energy of tides into electricity.
Like hydropower, tidal power has a bit of a history, with people as far back as the Romans using the tides to power mills. Now, however, tides are not a widely used form of power. It does have a lot of potential though.
The good thing about tides is that they are easy to predict. Because the relative motion of the Earth, Moon and Sun generates tidal energy, it is a practically inexhaustible form of energy that is far more reliable than wind energy or even solar.
Oh, that’s right, 80% of the Australian population lives within 50kms of the coast. So unlike some other power sources it is very close by.
While we’re on the subject of the ocean, let’s not forget wave power. Wave power is the transport of ocean surface waves and the capture of the energy that drives those waves to do something useful for us, like generate electricity.
The beautiful thing about wave power is that it’s a genuinely renewable source of energy. The World Energy Council has estimated that approximately 2 terawatts (2 million megawatts), about double current world electricity production, could be produced from the oceans via wave power alone. In Australia it is estimated that 1 million gigawatt hours of wave energy hits Australian shores annually.
What are we waiting for?
There are several small-scale operations trailing their wave and current capture contraptions around the world. The challenge is that they are all just that – contraptions and have a long way to go before being commercially viable. The industry is in its infancy. It will take time but the upside is massive.