In the continuing inquiry into which bodies and actors are likely to call for Renewable Gas, and why, I am going back to add extra comments to sectors I already discussed.
14. Power Grid Operators (Continued)
An Embarrassment of Electrons
Stories regularly bubble away, and rise to the surface from time to time, about how renewable power is being wasted, as grids don’t need it or can’t handle it.
There appears to be a whole phalanx of media commentators, who might identify as right-wing, and therefore be fans of shareholding and markets, who complain about wind turbines being “shut down” (or more accurately “shut out”) because it’s too windy. Funny, though, increasingly more wind turbines are being planted, almost as if there’s a strong return on capital investment in these zero carbon assets. Plus, these opinion-formers don’t seem to change their story from year to year, which is a tad strange :-
2018 : Wind farms paid £100m to switch power off
2020 : “Wind farms paid up to £3 million per day to switch off turbines”
It’s a losing argument, lads. Actually, no, it’s lost. The National Grid knew what it was doing when it agreed to adopt renewable electricity sources. There’s the whole Balancing Mechanism, and soon, there will be heaps of extra electricity storage, and the storage of the power of electrons in other forms of energy.
As time goes by, and reams of solar panels and crowds of wind turbines are added to the standing army of power grids in the developed and developing countries, because neighbouring countries will all be producing too much electricity at the same time – for example in a strong storm system or a very sunny day – it will not be possible to export electrons along interconnectors.
Oops, an embarrassment of electrons. The infrastructure and grid distribution people will be looking for anything that can act as a load sink. Sure, for an anticipated storage time of a few hours, using grid-integrated solid state batteries are going to be a boon. Except the scale of the energy storage required might far outweigh original scoping.
Will the power companies turn to flow batteries and other kinds of chemical looping systems for energy storage on windy Wednesdays and sunny Sundays ? It all depends on how stable these turn out to be – how many cycles of a unit can be done before maintenance or chemical refilling is required. Also, the containment of chemical batteries is a fairly major construction cost, and for safety reasons, it might be better if they were built into the ground – also saving on build materials. If the power companies need to go to the extent of digging for battery provision, why not produce synthetic gas from excess renewable power, and store that underground instead ? It would require much less in terms of containment and build. Nature has provided a fine example of how gases can be stored safely for millions of years underground – why, we could even use the now-emptied Natural Gas caverns to store synthesised methane.
It is at this point in the logic that a wise reviewer of energy will reflect on how there is now a bit of a competition for the provision of sub-surface storage of gases. Large, traditionally leading oil and gas companies are selling the idea of CCS – Carbon Capture and Storage, where all vagrant carbon dioxide should be plucked from whichever process, or even from the air itself, to be compressed and pumped underground for eternity – but actually a good deal shorter, because of tectonics and the natural long period natural Carbon Cycle. Modern, more conscious energy companies want to use the sub-surface to store carbon-free hydrogen, despite the fact that hydrogen molecules are incredibly small and incorrigibly mobile, seeping through even metals.
Whilst it is true that the world needs Renewable Hydrogen – hydrogen liberated from water and biomass by the action of renewable power – the best gas for energy storage is definitely Renewable Methane – made from Renewable Hydrogen. There is a strong parallel with natural processes : Natural Gas, which has been resident in the sub-surface for millions of years, is primarily methane in content.
Fine. Capture and lock away a bit of carbon dioxide underground. Bury CO2. But there is no gain in locking away a source of carbon that has no intrinsic fuel value. What’s more important is energy storage – so temporarily burying hydrogen and methane – which are ideal fuels. Although, as previously noted, methane is more stable and containable, theoretically. Methane gas emissions from oil and gas industry operations have been bad in some places and at some times : due to liberating methane from its millions-years sub-surface storage : this failing will need to be deal with when applications of Renewable Methane expand.
10. Industrial High Energy Consumers (Continued)
Developed and developing economies will continue to have industries with high levels of energy demand, causing high levels of carbon dioxide emissions : for products such as steel, glass, fuels, petrochemicals and cement. Processes in this sector are highly concentrated in terms of location, owing to the energy efficiency of highly centralised operation, and this would facilitate high volume carbon dioxide capture, and therefore lower-cost CCS – the underground, permanent sequestration of carbon dioxide.
However, in terms of capital expenditure barriers to new technologies, it would be less of a hurdle to implement low carbon synthetic gas production to meet energy demand; and in addition, provide energy-dense synthesised gases for storage which would have a future earnings potential. If syngas in high energy demand industries were to be made from renewable resources, so Renewable Gas, so Renewable Hydrogen, Renewable Methane and Renewable Carbon Monoxide, this would advance low carbon industry significantly.
Another question is that of speed-to-implementation : Renewable Gas for low carbon energy in energy-intensive industries is likely to be much faster to get going than industry-wide Carbon Capture and Storage.
In order for Renewable Gas to be called for in this sector, however, there would need to be a strong confidence that renewable electricity supplies were growing virtually exponentially, as cheap power will be essential. Renewable Gas will not only be a serious soak of excess renewable power load, it will also provide a way to capture and recycle process heat in energy-intensive industries – a matter of energy efficiency, which is highly important to make advances in.