Wind and solar generation are powering more and more of our electricity systems. Along with their zero-carbon electricity comes their variability and uncontrollable power output.
Utilities are increasingly tackling the variable nature of wind and solar power by building energy storage to shift available power from when it can be produced by nature to when it is most needed by the grid.
There is growing interest and possibilities in tackling the variability issue not by shifting available power to meet electricity demands, but by shifting electricity demands to meet available power.
One potential candidate flexible load candidate is producing hydrogen gas by splitting water using electrolysis. Producing low-cost hydrogen with minimal carbon emissions is currently viewed as a cornerstone of an energy transition away from carbon emitting sources.
Our new paper
We recently published a paper in Advances in Applied Energy considering producing hydrogen as a flexible electricity load (demand) in future low-carbon electricity systems.
We asked how the operations of future electricity systems would change if we introduced a small, flexible hydrogen producing load. Is there essentially “free” electricity available to a business who can choose to operate only when the sun is shining and wind is blowing? How much “free” electricity will there be?
We find that in systems with substantial wind and solar power, zero cost electricity is available sometimes and low-cost power is available almost always. In fact, in modeled systems powered exclusively by wind and solar power, zero-cost, zero-carbon power was available more than 95% of the time.
One enticing thing about flexible loads is when other electricity uses are pushing the grid to its maximum extent and power costs are high, flexible loads can simply throttle back or even turn off. This would save them considerable money and could save the grid from needing to expand generation capacity, a win-win situation.
However, if we really push the envelope with vast amounts of flexible loads like electric vehicles and by producing hydrogen, the grid’s generation capacity will eventually need to expand. After all, there is only so much zero-cost and low-cost power available in the original electricity system.
Many more interesting results and all the details can be found in the paper.
I am looking forward to continuing this line of work and further exploring the integration of hydrogen production with low-carbon electricity systems and how both can enable a low-carbon energy transition.