Energy storage solutions for intermittency in renewable power sources

Sustainable Energy Storage

One of the most dire and challenging crises faced by the human race today is the complete reliance on the generation of artificial power and energy in order to fuel the world and its daily functioning. The main problem is that the fossil fuels commonly used for these efforts are beginning to run out and prove themselves quite unsustainable. In response, of course, natural, renewable, and sustainable sources of energy have been identified for the purpose of alternative power generation. While these have met with some success, the new challenge now is to find ways of storing energy from sources like the wind and sun, which are intermittent. The main reason for such storage would be the fact that the greatest need for energy is not necessarily in tandem with when the wind or sun is at its highest.

The main problem associated with this is that the grid has to turn away power from intermittent sources when such power is not needed (Smedley, 2014). In this way, huge amounts of energy that could have relieved the burden on traditional power sources is simply lost. Wind farms, for example, generate revenue for power that is generated but not used when it is turned away by the grid. This is not conducive to a cost-effective environment.

To remedy this, Smedley (2014) suggests effective energy storage, which is a challenge by itself, since many storage technologies today are simply not advanced enough or big enough to store the amount of power that is being lost. Batteries, for example, can only store small amounts of power, while electric vehicles would need to be too numerous to be an effective solution for the current situation. The most popular current idea is pumped hydro. In this form of energy storage, excess energy is used to pump water along a slope, while the water is released downhill again when energy is required. The challenged associated with this is that the environment needs to be very specifically suitable, as in a very large area that includes hills and space for lakes.

Smedley (2014) offers a fourth solution, which is the use of electrolysis in water to transform excess electricity into hydrogen gas, which would be renewable. The author notes that, in the UK, a new system has been created by which the high intensity of energy usually required to create hydrogen is mitigated by a new system of electrolysis. This system would connect to the grid. Surges of power can then be used in the process to create high-pressure hydrogen. This, in turn, can then be used as a fuel for injection to the gas grid.

This system is known as "power-to-gas" energy. The system has been successfully set up and running in Frankfurt since 2013. A company in Germany has also followed suit with a project backed by the government. The power-to-gas system provides a dual action system, acting as both storage medium and power product. Further, it provides a way of circumventing the logistical and topographical problems associated with other methods of excess energy storage.