Additional energy consuming steps not shown: pumping water to the electrolyzer, purifying the water, compressing or liquefying to -423 F, pumping into storage container, the trucks to deliver H to stations costing $75 million each, since pipelines are super expensive and may leak, corrode, and explode (Zhao 2018). For hydrogen trucks that don’t exist because fuel cell technology is still far from commercial.

Preface. For all the reasons why hydrogen is not going to replace fossil fuels, see the other posts in they hydrogen category, especially Hydrogen: The dumbest & most impossible renewable.

As the Russian war with Ukraine is making clearer, we are far from being able to abandon fossil fuels, so perhaps that is why there are more hopium articles than usual to keep people convinced we can move to renewables and save the world climate change. And doing nothing to prepare for the coming energy crisis.

Hydrogen is the dumbest, most ridiculous energy alternative. It is insanely far from being renewable with the highest negative energy return of any alternative, because far more energy is used than you ever get back to split the hydrogen from natural gas or electrolyze it from water, compress or liquefy it, construct incredibly expensive and short-lived steel containers and pipelines, and deliver the hydrogen to non-existent hydrogen fuel cell heavy-duty trucks, locomotives, and ships. Fuel cell technology is far from commercial from the transportation that keeps all of us alive.

Hydrogen from water using electrolysis is 12 times more costly than natural gas, so no wonder “renewable” hydrogen from water is only made when an especially pure hydrogen is required, mainly by NASA for rocket fuel.

From Life After Fossil Fuels: A Reality Check on Alternative Energy:

There has to be a lot of whatever it is that replaces fossil fuels. No wonder hydrogen is seen as a possibility since H2O covers 70% of the planet. Pure hydrogen is the most potent “fossil” fuel (like) substance, so there should be lots of energy there. But free hydrogen in the atmosphere does not exist, it either escapes Earth’s gravity or more likely binds tightly with oxygen. And once hydrogen has found a nice oxygen to snuggle with it does not want to leave. Not at all. That’s why it takes a whole lot of energy to pry these “abundant” hydrogen atoms away from its buddy oxygen—in fact about 50% more energy than you would gain by reoxidizing it. Foiled again by thermodynamics! But if you have pure hydrogen (we will not ask where you got it!) AND some pure oxygen you can use them to make an electric current in a fuel cell by reoxidizing them. Although the first hydrogen fuel cell was invented by Sir William Robert Grove in 1839, hydrogen fuel cells are still far from being commercial for heavy-duty trucks (Friedemann 2016). A big problem is that the specialized membrane required is easily poisoned by impurities in the fuel, and replacing them can be more expensive than the fuel!

The amount of water to make green hydrogen is not a drop in the bucket. After 18 tons of impure water are purified, there will be nine tons of water left, which can be electrolyzed to produce one ton of hydrogen. It will take energy to move all this water to the electrolyzer. Although the electrolyzer facility can be placed next to a river or ocean, this will be possible only if it is a cost-effective place to put a wind or solar farm (Webber 2007; Slav 2020). Hydrogen is not a drop-in fuel, nor can the natural gas pipeline system or service stations be used for distribution because hydrogen leaks as well as corrodes metal. According to former Secretary of Energy Steven Chu (2020), hydrogen seeps into metal and embrittles it, a material problem that has not been solved for decades and may never be solved. Meanwhile, hydrogen is stored in expensive austenitic stainless steel containers and pipelines that delay corrosion, and must be carefully maintained and monitored, since embrittlement can result in catastrophic explosions with loss of property and life.

Hydrogen hopium in the news:

2022 Advanced Clean Energy Storage Project Receives $500 Million Conditional Commitment from U.S. Department of Energy.  But guess what?  The project will be in Delta Utah because it is one of the four states in the U.S. where there are deep underground salt domes to try to store hydrogen in (this hasn’t been done before and since hydrogen is the universe’s tiniest element, likely to escape).  In addition, 33% of Utah is in an extreme drought in 2022, which includes Delta Utah in Millard County. And what will this hydrogen do?  Provide 30% of the energy to a 70% natural gas powered facility. This is not so much hydrogen power as corporate welfare for Black & Vetch, Mitsubishi Power, WSP, and NAES corporation!

What is hopium? Irrational or unwarranted optimism. An addiction to false hopes. And Hopium makes fuel cell hydrogen cars!  What could be more suitable for today’s post.

Alice Friedemann  www.energyskeptic.com  Author of Life After Fossil Fuels: A Reality Check on Alternative Energy; When Trucks Stop Running: Energy and the Future of Transportation”, Barriers to Making Algal Biofuels, & “Crunch! Whole Grain Artisan Chips and Crackers”.  Women in ecology  Podcasts: WGBH, Jore, Planet: Critical, Crazy Town, Collapse Chronicles, Derrick Jensen, Practical Prepping, Kunstler 253 &278, Peak Prosperity,  Index of best energyskeptic posts

***

Making Hydrogen from Water 

Only 4% of hydrogen is made from water via electrolysis. It is done when the hydrogen must be extremely pure. Since most electricity comes from fossil fuels in electricity generating plants that are 30% efficient, and electrolysis is 70% efficient, you end up using four units of energy to create one unit of hydrogen energy: 70% * 30% = 21% efficiency (Romm 2004).

Fresh water hydrogen competes with agriculture and drinking water, so ideally hydrogen would be made from more abundant sea water. But that would require expensive purification and desalination, since electrolysis turns chloride ions into toxic chlorine gas and degrades the equipment. New technology, such as membranes, catalysts, and electrode materials need to be invented (Tong 2020).

Sure, renewables could generate the electricity, but only about 8.4% of power comes from wind (EIA 2021a), with a whopping 26% from Texas, which is on its own grid, not sharing with any other states.  Another 9 states produce the vast majority of wind power mainly in the central states, with the entire South East generating almost no wind at all.

And only 3% of U.S. Electricity comes from solar power (EIA 2021b). Once again, it is regional, with the vast majority of solar power produced in the desert southwest. So how can hydrogen ever be renewable? There’s no national grid. About 65% of electricity is from natural gas and coal, 19% from nuclear power plants with radioactive waste that last hundreds of thousands of years and for which there are zero plans of disposal in the U.S. (only Finland is building a waste repository due to come online in 2024).

Producing hydrogen by using fossil fuels as a feedstock or an energy source defeats the purpose, since the whole point is to get away from fossil fuels. The goal is to use renewable energy to make hydrogen from water via electrolysis. When the wind is blowing, current wind turbines can perform at 30–40% efficiency, producing hydrogen at an overall rate of 25% efficiency — 3 units of wind energy to get 1 unit of hydrogen energy. The best solar cells available on a large scale have an efficiency of 10%, or 9 units of energy to get 1 hydrogen unit of energy. If you use algae making hydrogen as a byproduct, the efficiency is about 0.1 percent (Hayden 2001). No matter how you look at it, producing hydrogen from water is an energy sink. If you want a more dramatic demonstration, please mail me ten dollars and I’ll send you back a dollar.

Webber, M.E. 2007. The Water Intensity of the Transitional Hydrogen Economy. Environmental Research Letters 2. 

Hydrogen production using thermoelectric powered electrolysis is significantly more water intensive than gasoline production. If 60 billion kg of hydrogen are manufactured a year by electrolysis, it will consume approximately 143 billion gallons of water just as the feedstock. Furthermore, because electrolysis is a very energy-intensive process, manufacturing 60 billion kg of hydrogen annually with that method would require vast amounts of electricity.

Since thermoelectric power makes up 90% of the fuel mix in the US, it is likely that some portion of that power for electrolysis will consequently require significant amounts of water for cooling.

Using recent data for water withdrawals by the thermoelectric sector and overall energy consumption, it can be deduced that the water withdrawal and consumption increases for a thermoelectrically powered hydrogen economy are significant. The calculated water withdrawals for electrolytic hydrogen production could increase by anywhere from 27 to 97%, depending on electrolyzer efficiencies from 60 to 90% and the fraction that is produced by thermoelectric power (from 35 to 85%), while consumption (including evaporative losses and conversion of feedwater into hydrogen) might increase by 0.5–1.7 trillion gallons per year.

On a per unit basis, thermoelectric power generation for electrolysis will on average withdraw approximately 1100 gallons of cooling water and will consume 27 gallons of water as a feedstock and coolant for every kilogram of hydrogen that is produced using an electrolyzer that has an efficiency of 75%.

Given that water withdrawals have remained steady for decades, this increase in water use represents a significant potential impact of the hydrogen economy on a critical resource, and thus presents a serious technical and public policy problem. If minimizing the impact of water resources is a priority and electrolysis becomes a widespread method of hydrogen production, it is likely that the power for electrolytic hydrogen production will have to come from non-thermoelectric, non-hydroelectric and non-irrigated renewable sources. Consequently, almost all the new electricity generating capacity for hydrogen production would need to be from hydrogen production pathways that do not use much water (such as wind or solar), or effective water-free cooling methods (e.g. air cooling) will need to be developed and widely deployed.

The total water withdrawals for thermoelectric cooling would be anywhere from 19 trillion gallons annually for 90% efficient electrolyzers if 35% of the hydrogen is produced by thermoelectrically powered electrolysis, to nearly 69 trillion gallons for electrolyzers with 60% efficiency if 85% of the hydrogen is produced by thermoelectrically powered electrolysis. These withdrawals correspond to an additional 52–189 billion gallons per day on top of the 195 billion gallons of daily withdrawals already in place for thermoelectric power, representing a potential increase of between 27 and 97%. The total water consumption would increase by between 0.5 and 1.7 trillion gallons over the course of a year for the same cases, presumably mixed 70% freshwater and 30% saline according to the existing ratios. Note that freshwater consumption in 1995 for thermoelectric applications was 1.2 trillion gallons [14].

For comparison, the reader is reminded from before that gasoline production consumes 1–2.5 gallons of water per gallon of gasoline that is produced, and hydrogen produced via SMR consumes approximately 4.6 gallons kg^–1 of hydrogen that is produced [14], both of which are much lower than the consumption of 27 gallons of water per kilogram of hydrogen for electrolyzers with 75% efficiency operated by average thermoelectric power. Switching to hydroelectric power for electrolysis, which consumes 18 gallons kWh^–1 due to increased evaporation at man-made reservoirs [20], would increase the water consumption to approximately 950 gallons of water per kilogram of hydrogen that is produced with electrolyzers operating at 75% efficiency. Note that withdrawals for hydroelectric power are considered to be zero by convention. These values are summarized in table 3.

Table 2 also lists the annual electricity requirements to produce hydrogen in 2037 based on the fraction of the projected 60 billion kg that is produced by electrolysis as opposed to other pathways (values from 35 to 85% are listed) and as a function of electrolyzer efficiency. If highly efficient electrolyzers are used (e.g. 90% efficient) and only 35% of the 60 billion kg of hydrogen is produced by electrolysis, then 827 billion kWh of electricity will be required annually. If inefficient electrolyzers are used (e.g. 60% efficient) and a great preponderance of the 60 billion kg of hydrogen is produced by electrolysis (e.g. 85%), then 3351 billion kWh of electricity will be required annually.  Total annual electricity generation in the US in 2005 was 4063 billion kWh [18]. Thus, producing a fraction of hydrogen from electrolysis, even for very efficient systems, requires significant additional amounts of electricity to be generated.

The indirect water use that is necessary for the power plants depends on the type of power source: thermoelectric power uses water as a coolant, while renewable sources such as wind, solar and hydroelectric do not use water as a coolant. Though hydroelectric power does not use cooling water, it has high water consumption through increased evaporation at man-made reservoirs [20]. It is important to note that more than the 90% of the electricity in the US is generated through thermoelectric processes (either fossil-fuel combustion, biomass combustion, or nuclear reactions). Consequently, it can be expected that a significant fraction of power for electrolysis would be derived from thermoelectric sources that require cooling water.

According to the US Geological Survey, in 2000, thermoelectric power was responsible for about 48% of all freshwater and saline-water withdrawals in the US, requiring 195 billion gallons per day in total, and remaining roughly stable since 1985. Of those withdrawals, approximately 70%, or 132 billion gallons per day, was fresh, which is about the same amount required by the agriculture sector (predominantly for irrigation) [21]. Nearly 99% of all thermoelectric withdrawals were from surface water sources [21], with almost all of the water returned to the source without being consumed (though at a higher temperature and with a different quality) [14]. Approximately 3% (or 3.3 billion gallons per day) of the freshwater withdrawals were consumed by evaporation [14].

A comparison of the amount of water used by the thermoelectric sector in 2000 with the amount of electricity generated by thermoelectric sources in 2000 yields an average water withdrawal of 20.6 gallons per kilowatt hour for the nation’s entire thermoelectric fuel mix [21, 22]. Notably, the water withdrawals and fuel mix have not changed very much between 2000 and 2005: in 2000, the total electricity generation was 3840 billion kWh, of which 90% was from thermoelectric power; in 2005, even after significant increases in wind and solar power, the total electricity generation was 4063 billion kWh, of which 90% was from thermoelectric power; and the DOE’s projections out to 2030 show aggressive increases in renewable power, but also show that thermoelectric power is expected to remain 90–91% of the fuel mix [18, 22]. Consequently, it is reasonable to expect that some portion of the power for electrolysis will be derived from thermoelectric sources.

Note that this estimate for water withdrawals per kilowatt hour of generation is an average over geographic locations, cooling systems (e.g. once-through versus open-loop, etc), fuel sources, and power plant designs. There is significant variability of water use, however, with some thermoelectric power plants requiring up to 30–50 gallons kWh^–1 for once-through cooling [23]. And, as noted above, a portion of the water withdrawals for thermoelectric cooling are consumed by evaporation, typically in the range of between 0.2 and 0.72 gallons kWh^–1 [23]. It is also worth noting that nuclear power is often cited as a suitable carbon-free source of electricity for hydrogen production [2, 10–12, 17], but its water consumption for thermoelectric cooling is at the higher end of the typical range, at 0.4–0.72 gallons kWh^–1 [23]. Overall, the average US water evaporation at thermoelectric plants is 0.47 gallons kWh^–1 [20].

3.4. Total water use for electrolytic hydrogen production

Using 20.6 gallons kWh^–1 of average water withdrawals for thermoelectric cooling, we can estimate the water use for hydrogen production depending on the fraction that is powered by thermoelectric sources and the electrolyzer efficiencies, as shown in figure 1 for trillions of gallons per year. On a per unit basis, thermoelectric power generation will withdraw approximately 1100 gallons of cooling water on average per kilogram of hydrogen that is produced for an electrolyzer with 75% efficiency. Using 0.47 gallons kWh^–1 of average water consumption for thermoelectric cooling, plus 2.38 gallons kg^–1 of water as a feedstock for hydrogen, we can estimate the total water consumption of hydrogen production at 60 billion kg per year, depending on the fraction that is produced by thermoelectric power and for a range of electrolyzer efficiencies, as shown in figure 2 for billions of gallons per year. On a per unit basis, thermoelectrically powered electrolysis will consume 27 gallons of water as a feedstock and coolant for every kilogram of hydrogen that is produced for an electrolyzer with 75% efficiency. As expected, as more hydrogen is produced with thermoelectric power, the total water intensity (withdrawals and consumption) increases. Furthermore, as electrolyzer efficiencies improve, the total water intensity decreases. For reference, the thermoelectric sector withdrew 72 trillion gallons of water in 2000 [21].

References

Chu S (2020) Steven Chu: Lessons from the past and energy storage for deep renewables adoption. Stanford University.https://gef.stanford.edu/events/steven-chu-lessons-past-and-energystorage-deep-renewables-adoption.

EIA (2021a) The United States installed more wind turbine capacity in 2020 than in any other year. U.S. Energy Information Administration.

EIA (2021b) Solar generation was 3% of U.S. electricity in 2020… U.S. EIA.

Friedemann AJ (2016) When trucks stop running: Energy and the future of transportation, chapter 9. Springer

Hayden HC (2001) The Solar Fraud: Why Solar Energy Won’t Run the World. Vales Lake Publishing.

Romm JJ (2004) The Hype About Hydrogen: Fact and Fiction in the Race to Save the Climate. Island Press, 154.

Slav I (2020) The green hydrogen problem that no one is talking about. Oilprice.com

Tong W, et aL (2020) Electrolysis of low-grade and saline surface water. Nature Energy.

Webber, M.E. 2007. The Water Intensity of the Transitional Hydrogen Economy. Environmental Research Letters 2.

Zhao H, Qian W, Fulton L, et al (2018) A comparison of zero-emission highway trucking technologies. University of California. https://doi.org/10.7922/G2FQ9TS7