Model of a combined nuclear and wind power facility integrated with hydrogen production

NuWind is a concept developed by Dr. Miller and Dr. Romney Duffey at CRNL in the first few years of the 21st Century. Using global, strategic and market analyses they showed, by actual example, the potential synergism between wind and nuclear energy systems. By adopting a balanced portfolio of electricity and hydrogen production that is market driven, a generation mix of advanced nuclear designs with supplementary wind power provides a route towards a secure, sustainable and safe energy future. Primary energy supply is on the threshold of a revolution as profound as utilization of carbon-based fuels by the Industrial Revolution.


Improved energy efficiency is insufficient to bring CO2 emissions under control since the new revolution must cope with rapid expansion of energy demand in the economies of the Developing World as they climb toward Developed World levels of wealth. Three broad options exist for acceptable, primary energy supply: nuclear, renewables, and carbon with sequestration. From all of these, energy will emerge increasingly as electricity and require some form of storage. Hydrogen is ideal both for storage of electricity and as a transportation fuel producing minimal greenhouse gas emissions.


The required scale of new primary energy deployment is so large that choosing between the three supply technologies is pointless: one should identify ways in which they can most effectively be blended. NuWind is one such blend. It addresses the problem of wind’s short-term and seasonal intermittency and unpredictability. The extent to which wind’s variability can be absorbed as electricity depends on the mix of other generation capacity on a power grid but wind power can usually contribute only a fairly small percentage before the need for back-up capacity becomes burdensome. This has led to the suggestion of converting wind-generated electricity into hydrogen by electrolysis. However, simple analysis shows that wind’s low average output inflates the cost of electrolysis equipment beyond economic competitiveness.
With NuWind, judicious application of time-of-day variability in the value of electricity subsidizes the cost of electrolytic equipment. When the value of electricity is high, electricity is sold to the grid. When the value of electricity to the grid is low, electricity from both nuclear and wind sources are converted into hydrogen using cells designed to handle varying current density. If the wind is blowing, the current to the electrolysis cells is turned up. Low-cost cavern storage for hydrogen accommodates seasonal swings in the wind component. Using hourly electricity price data from Ontario and Alberta and typical hourly wind data, the economics of large-scale hydrogen production by NuWind are shown to be comparable with those of steam-methane reforming with sequestration.


Over a wide range of electricity to hydrogen ratios, the estimated cost of bulk, undistributed hydrogen production by Nu Wind is below the US DOE’s target of 2000 $/tonne (all dollars quoted are U.S.). All nuclear and aeolian generation is always available to the grid at times of high demand. Synergistically, the conversion of water to hydrogen by electrolysis facilitates low-cost production of heavy water, which is used as a moderator in Canadian nuclear reactors as well as in a rapidly growing range of non-nuclear applications.


(A Miller – 2018 February)