A new system can transform thousands of hills in the UK into large batteries. A team of engineers have developed a system which would allow Hydropower to store and release power within gently sloping hills and without the huge dams currently needed.
The idea of these small hydropower systems, is that we could build many of these tiny dams for far less than just a few large ones. More importantly, it would come with far less negative issues to those that come with historic large dams (for instance the proposed dam which threatens the future of 8th great ape species the Tapulani Orangutan).
This proposal would work like normal dams. When there was a surplus of power, this would be used to pump water to the top of the hill, and then the water would be released when the power was required. Like typical dams, releasing the energy and turning it into electricity out of this system would be relatively fast. Indeed these dams would respond almost as fast as a lithium battery, the advantage being that this system will never lose capacity.
Given the smaller storage facility of a pool (at the top and bottom of the hill) they would use a mineral rich fluid that weighs roughly two and a half times that of water, allowing the amount of electricity to be created that would usually need a dam twice as high. Hills that were over 200m high could be used.
Analysis has suggested that there are about 700 sites which could host these micro hydropower plants. It is thought that this would be able to create roughly 7GW of energy storage. To put that in perspective there are currently roughly 1GW of power storage in the uk, so this would make a large difference in our storage capability.
This is not a significant amount of power considering that the UK uses hundreds of gigawatts of power a day. However, what you have to realize is that the purpose of power storage is not to allow the country to run for weeks.
We need power storage to be able to usefully use the clean energy that we are able to produce. The sun does not always shine, and the wind does not always blow. However, with significant amounts of storage, what we can do, is make sure that the power that is generated cleanly is available when it is needed. Now it is true that this is just one form of power storage, however we are going to need to be able to store tens or hundreds of gigawatt hours in order to fully ditch fossil fuels. One of the things that these plants are likely to do, is allow us to get rid of peaker plants. These are fossil fuel powered plants which only run when demand is particularly high, they are usually highly polluting, and due to the fact that they only run some of the time, are very expensive.
Is this going to allow the UK to go 100% clean energy as soon as it is installed? No, of course not. It is however an important step that might reduce our need for the most polluting forms of energy generation by a significant amount. If we wish to hit our target of net zero emissions, we need to do this and all the other green solutions that we have. One big advantage these systems will have over batteries is longevity – the tank gives you the amount of power that you can store. Given the tank will remain the same size, a 1mw system will still be able to deliver 1mw of storage in 20, 30 50 years. What is more, while there are countries in the world which are too flat for these sources of battery, there are many places well suited. It is also true that given these hydropower systems are hidden out of sight, they can be built in beautiful places without such high concern over destroying the view.