The one thing that stands between very large scale energy production from wind and solar, and other renewables, is the requirement for efficient storage of excess production for the generation of electricity, when the wind is not blowing and the sun is not shining.
There has been a lot of focus and growth in the use of Lithium batteries for peak shaving storage of electricity, often at the power grid or power generator, however this form of storage while reducing in price has a very high capital cost. The ‘holy grail’ for renewables is an efficient method of storage and even transport of excess production. While the use of hydroelectric storage is very useful, it is limited and only available in areas where topography lends itself hydroelectric generation.
There has been a growing emphasis on the production of Hydrogen gas from excess wind and solar power in recent years. This can be used very effectively by injecting the Hydrogen directly into natural gas pipelines. Depending on the calorific value of the natural gas in the pipeline, typically around 10% hydrogen gas can be introduced into the pipeline. This is a very efficient use of excess hydrogen, however it is limited and the hydrogen itself is not cheap to store on a large scale.
What would be ideal for storage, is an easily produced and stored liquid which can be used directly in a generator.
The ‘holy grail’ is at hand! In the last few years there has been significant success at several institutes in the development of new catalytic processes to generate Methanol from Carbon Dioxide, sequestered from the atmosphere, combined with Hydrogen. The process has been around for a long time, but it was very inefficient.
What is new is that improved catalysts have been formulated which both reduce the temperature of reaction, thus reducing energy input, and enable the expensive catalysts to be used many times. This reduces the cost of production of Methanol and increases efficiency to the point where the development of a commercial scale Methanol Plant becomes economic.
This step change in the viability of very large scale renewable power generation has happen almost without notice. The impact of this technology in the energy mix over the next few years will become very noticeable. This will drive the development of very large scale wind and solar installations, which in turn will drive down the cost of those wind and solar installations with large economies of scale and enable further investment in improved wind and solar technology.
Finally - Methanol is not only a useful storable fuel for power generation, it can also be used in vehicle engines, in fuel cells and as a feedstock for plastics and chemicals.