Hydrogen is likely never to become a viable solution to the energy storage conundrum – Can it be achieved?
What I call the “energy storage conundrum” is an obvious but largely unrecognized problem that electricity generated from intermittent renewable energy sources like wind and solar does not. can keep the grid running without some form of energy storage to meet customer demand during periods of low output. These periods of low wind and sun production are frequent – for example, quiet nights – and can last a week or more in the case of overcast and calm winter weather.
If the plan is to power the entire United States with wind and solar facilities, and if we assume that wind and solar facilities will be built enough to generate energy equal to Over the course of a year, we need to calculate how much inventory is needed to balance excess production time with insufficient production time to get through the year without power outages. The challenge of getting through an entire year can require more storage than just getting through a weeklong wind/sun drought, because both wind and sun are seasonal, producing more in some seasons than others. other season.
Previous posts on this blog have cited some authoritative calculations of the amount of storage required for different jurisdictions to get through an entire year with only wind and solar to generate electricity. In the case of the entire United States, This post is from January 2022 job description by Ken Gregory, who calculates the storage requirement, based on current electricity consumption, about 250,000 GWH for a year’s use. Then if you assume as part of a decarbonization project is to electrify all the currently non-electrified sectors of the economy (transportation, home heating, industry, agriculture, etc.), storage requirements will increase approximately threefold, to 750,000 GWH. If the battery meets that storage requirement and we price the required storage at the price of the best battery available (Tesla type lithium ion battery), we will receive an upfront capital cost of approx. hundreds of trillions of dollars. That cost alone would be a large multiple of the entire GDP of the United States, and would clearly make the entire decarbonization project impossible. In addition, lithium-ion batteries (and all other existing batteries) are incapable of storing energy for months on end, such as from summer to winter, not dissipating heat, and then discharging in additional month period. . In other words, the fantasy of an all-wind/solar economy powered by batteries alone would quickly enter an impregnable wall.
So is there another approach to decarbonization that might work? With nuclear blocked by the same environmentalists who oppose all fossil fuel use, there are few options. The most sensible would be to use hydrogen as a storage medium to balance the random variability of wind and solar power production.
It’s not like no one thought of this until now. Indeed, for politicians and activists who can freely articulate theoretical solutions without worrying about practical obstacles or costs, hydrogen seems unlikely. easier. With hydrogen, you can completely cut carbon out of the energy cycle: make hydrogen out of water, store it until you need it, and then when you need it, burn it to generate energy with just water. is a by-product.
Back in 2003, Then-President George W. Bush proposed exactly such a system in his State of the Union speech.:
During his 2003 State of the Union Address, President Bush launched his Hydrogen Fuel Initiative. The goal of this initiative is to work with the private sector to accelerate the research and development needed for the hydrogen economy. The Presidential Hydrogen Fuel Initiative and FreedomCAR Partners are providing nearly $1.72 billion to develop hydrogen-powered fuel cells, hydrogen infrastructure technology, and advanced automotive technology. The President’s initiative will enable the commercialization of fuel cell vehicles within the 2020 timeframe.
Fuel cell cars (that is, hydrogen fuel) in 2020. Nothing for it!
You probably didn’t see any large numbers of hydrogen-fueled cars on the roads here in 2022. Evolution of the project to produce hydrogen by carbon-free electrolysis of water (double) when called “blue hydrogen”) ? This is the word JP Morgan Wealth Management Annual Energy Report 2022 (page 39):
Current green hydrogen production is negligible. . . .
The solution seems too obvious, but no one does it. What’s wrong with everyone?
Summarizing the answer is that hydrogen in the free gas form is much more expensive than good old natural gas (aka methane or CH4), and once you have it, it is inferior in every way to natural gas like a fuel to run the energy system (aside from carbon emissions, if you think that’s a problem). Hydrogen is much more difficult and expensive than natural gas to transport, store, and process. It is much more dangerous and can explode. It is much less dense in mass, which makes it particularly less useful for transportation applications such as automobiles and aircraft.
And of course there are no large-scale demonstration projects to show how a hydrogen-based power system works or its cost after including all the extras and current unknowns. at not only to manufacture it but also to transport and handle it. safe.
Here are just some of the problems that arise when considering hydrogen as a way to decarbonize:
- The cost of “green” hydrogen compared to natural gas. In recent years, before a few months ago, Natural gas prices have fluctuated from about $2 to $6 per million BTU in the U.S. The price spike over the past few months has brought the price of natural gas to around $9/MMBTUs. Meanwhile, according to December 2020 piece at Seeking Alpha, the price of “green” hydrogen generated by electrolysis of water ranges from $4 to $6 per kilogram which, according to Seeking Alpha, means $32 to $48 per MMBTU. In other words, even with the recent dramatic increase in the price of natural gas, it is still three to five times cheaper to obtain “green” hydrogen. There are some who predict the price of “green” hydrogen will plummet in the future, and the price of natural gas will also continue to rise. Probably. But at current prices or anywhere near it, no one is going to buy big “green” hydrogen as a backup fuel for intermittent renewables; and if there were no buyers, no one would mass produce those things.
- How much solar/wind generating capacity is needed to produce “green” hydrogen? It really takes a surprisingly large amount of solar panels and/or wind turbines to generate enough “green” hydrogen to be a meaningful factor in supporting the largely powered grid. by the sun and the wind. The work Seeking Alpha calculated how much power the solar panel on the nameplate would take to produce enough “green” hydrogen to power a small (288 MW) GE turbine generator. The answer is, the solar panel capacity to do the work would be roughly ten times the capacity of the plant using hydrogen: “Consider the widely deployed GE 9F.04 gas turbine, which produces 288 MW of electricity. With 100% hydrogen fuel, GE says that this turbine will use about 9.3 million CF or 22,400 kg of hydrogen per hour. With an 80% efficient electrolytic energy cost of 49.3 kWh/kg, to produce that one hour supply of hydrogen would require 1,104 MWh of electricity for electrolysis. To generate hydrogen to run a turbine for 12 hours (from dusk to dawn) would require 12 x 1,104 MWh, or 13.2 GWh. With a typical solar power factor of 20%, that would require about 2.6 GW of solar nameplate capacity dedicated to generating hydrogen to fuel this 288 MW generator overnight. “. Given the enormous losses involved in producing hydrogen and then converting it back into electricity, it is almost impossible to think that the process could be cost-competitive with just burning natural gas.
- Creating enough “green” hydrogen to power the country means electrolysis of the oceans. The ocean is a truly unlimited source of water, but the supply of fresh water is limited. If you electrolyze salt water, you will get large amounts of very toxic chlorine. There are people working on solutions to this huge problem, but right now all are in the laboratory stage. The added cost of getting your “green” hydrogen from the ocean is a complete wild card.
- Hydrogen has a much lower energy density than gasoline by volume. For many purposes, and especially for fuel transportation purposes, it is relevant that hydrogen has a much lower density than gasoline by volume. Even liquid hydrogen has an energy density by volume of only 1/4 of gasoline (8 MJ/L vs 32 MJ/L), which means a much larger fuel tank; and liquid hydrogen needs to be kept at the extremely cold temperature of -253 degrees Celsius. Alternatively, you can compress the gas, but then you’re talking like a 10x energy density disadvantage. Compressing the gas or converting it to a liquid would require a large amount of additional energy, which is an additional cost that has not been included in the calculations.
- Hydrogen makes steel pipes more brittle. Hydrogen is much more difficult to transport and handle than natural gas. Most current gas pipelines are made of steel, and hydrogen has an effect on steel known as “settlement,” which causes pipes to develop cracks and leaks over time. Cracks and leaks can lead to explosions. In addition, because of the issue of volumetric energy density, existing natural gas pipelines can carry less energy if used to carry hydrogen.
I don’t know how much more our energy would cost if we were forced to get rid of all the hydrocarbons and switch to wind and sun powered by “green” hydrogen – and so would anyone else. An educated guess would be that the total cost of energy would multiply by something in the five to ten range.
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