As talked about within the final publish, my new power storage report, The Power Storage Conundrum, principally offers with points which have beforehand been mentioned on this weblog; however the Report goes into appreciable additional element on a few of them.
One challenge the place the Report comprises a lot further element is the difficulty of hydrogen as a substitute for batteries because the medium of power storage. For examples of earlier dialogue on this weblog of hydrogen because the medium of storage to again up {an electrical} grid see, for instance, “The Fool’s Reply To International Warming: Hydrogen” from August 12, 2021, and “Hydrogen Is Unlikely Ever To Be A Viable Resolution To The Power Storage Conundrum” from June 13, 2022.
At first blush, hydrogen could appear to supply the apparent answer to essentially the most troublesome problems with power storage for backing up intermittent renewable era. Particularly, the seasonal patterns of era from wind and solar require a storage answer that may obtain extra energy manufacturing regularly for months in a row, after which discharge the saved power over the course of so long as a 12 months. No current battery know-how can do something like that, largely as a result of a lot of the saved power will merely dissipate whether it is left in a battery for a 12 months earlier than being referred to as upon. But when you can also make hydrogen from some supply, you’ll be able to retailer it someplace for a 12 months and even longer with out important loss. Downside solved!
Properly, there have to be some drawback with hydrogen, or in any other case individuals would already be utilizing it extensively. And certainly, the issues with hydrogen, whereas completely different from these of battery storage, are nonetheless equivalently big. Principally, to supply massive quantities of hydrogen with out producing the very greenhouse fuel emissions you might be looking for to keep away from, seems to be enormously expensive. After which, after getting the hydrogen, distributing it and dealing with it are very difficult.
In contrast to, say, oxygen or nitrogen, that are ubiquitous as free gases within the environment, there may be virtually no free hydrogen out there for the taking. It’s all certain up both in hydrocarbons (aka fossil fuels — coal, oil and pure fuel), carbohydrates (aka vegetation and animals), or water. To acquire free hydrogen, it have to be separated from one or one other of those substances by the enter of power. The simplest and least expensive solution to get free hydrogen is to separate it from the carbon in pure fuel. That is generally completed by a course of referred to as “steam reformation,” which ends up in the carbon from the pure fuel getting emitted into the environment within the type of CO2. In different phrases, acquiring hydrogen from pure fuel by the cheap strategy of steam reformation provides no advantages by way of carbon emissions over simply burning the pure fuel. So, in case you insist on getting free hydrogen with out carbon emissions, you will must get it from water by a strategy of electrolysis. Hydrogen obtained from water by electrolysis is thought by environmental cognoscenti as “inexperienced hydrogen,” due to the avoidance of carbon emissions. Sadly, the electrolysis course of requires a really massive enter of power.
How a lot is it going to value to supply inexperienced hydrogen because the storage medium for a primarily wind/photo voltaic grid? My Report first notes that as of right now there may be virtually no manufacturing of this inexperienced hydrogen factor:
Thus far, there was virtually no industrial manufacturing of inexperienced hydrogen, as a result of electrolysis is far more costly than steam reformation of pure fuel, and is due to this fact uneconomic with out authorities subsidy. The JP Morgan Asset Administration 2022 Annual Power Paper states that ‘Present inexperienced hydrogen manufacturing is negligible…’
So we don’t have any massive functioning initiatives from which we will get figures for a way costly inexperienced hydrogen goes to be. Within the absence of that, I believed to undertake an train to calculate how a lot capability of photo voltaic panels it could take to supply 288 MW of agency energy for some jurisdiction, the place the panels may both present electrical energy on to the customers or alternatively produce hydrogen by electrolysis that could possibly be saved after which burned in an influence plant to supply electrical energy. (The 288 MW determine was chosen as a result of GE produces a turbine for pure fuel energy vegetation with this capability, and says that it may possibly convert the turbine to be used of hydrogen because the gasoline.). Right here is that train as written up in my Report:
Take into account a jurisdiction with regular electrical energy demand of 288 MW. . . . The electrical energy wants of our jurisdiction might be absolutely equipped by burning pure fuel within the plant. However now suppose we wish to use photo voltaic panels to offer the electrical energy and/or hydrogen for the plant ample to produce the 288 MW agency all year long. What capability of photo voltaic panels should we construct? Here’s a calculation:
• Over the course of the 12 months, the jurisdiction will use 288 MW × 8760 hours = 2,522,880 MWh of electrical energy.
• We begin by constructing 288 MW of photo voltaic panels. We’ll assume that the photo voltaic panels produce at a 20% capability issue over the course of a 12 months. (Very sunny locations such because the California desert might method a 25% capability issue from photo voltaic panels, however cloudy locations such because the Jap US and all of Europe get far lower than 20% of capability; within the UK, typical annualised photo voltaic capability components are below 15%). That signifies that the 288 MW of photo voltaic panels will solely produce 288 × 8760 × 0.2 = 504,576 MWh in a 12 months.
• Due to this fact, along with the 288MW of photo voltaic panels instantly producing electrical energy, we’d like further photo voltaic panels to supply hydrogen to burn within the energy plant ample to generate the remaining 2,018,304 MWh.
• At 80% effectivity within the electrolysis course of, it takes 49.3 kWh of electrical energy to supply 1 kilogram of hydrogen. GE says that its 288 MW plant will burn 22,400 kilograms of hydrogen per hour to supply the complete capability. Due to this fact, it takes 49.3 × 22,400 = 1,104,320 kWh, or roughly 1,104 MWh of electrical energy to acquire the hydrogen to run the plant for one hour. For the 1,104 MWh of electrical energy enter, we get again 288 MWh of electrical energy output from the GE plant.
• Because of the 20% capability issue of the photo voltaic panels, we might want to run the plant for 8760 × 0.8 = 7008 hours throughout the 12 months. That signifies that we’d like photo voltaic panels ample to supply 7008 × 1104 = 7,736,832 MWh of electrical energy.
• Once more due to the 20% capability issue, to generate the 7,736,832MWh of electrical energy utilizing photo voltaic panels, we are going to want panels with capability to supply 5 instances that a lot, or 38,684,160 MWh. Dividing by 8760 hours in a 12 months, we are going to want photo voltaic panels with capability of 4,416 MW to generate the hydrogen that we’d like for backup.
• Plus the 288MW of photo voltaic panels that we started with. So the entire capability of photo voltaic panels we might want to present the 288MW agency energy utilizing inexperienced hydrogen as backup is 4,704 MW.
Or in different phrases, to make use of pure fuel, you simply want the 288 MW plant to offer 288 MW of agency energy all year long. However to make use of photo voltaic panels plus inexperienced hydrogen backup, you want the identical 288MW plant to burn the hydrogen, plus greater than 16 instances that a lot, or 4,704 MW of capability of photo voltaic panels, to offer electrical energy instantly and to generate ample hydrogen for the backup.
That calculation assumed a 20% capability issue of manufacturing from the photo voltaic panels over the course of a 12 months. It seems that precise photo voltaic capability components are extra like 10-13% for Germany, 10-11% for the UK, and about 12.6% in New York. (California, with few clouds, will get capability components considerably in extra of 25%.). Doing the identical sequence of calculations utilizing a ten% capability issue for the photo voltaic panels, you will want one thing like 9,936 MW of photo voltaic panels to offer your 288 MW of agency energy for the 12 months, with the inexperienced hydrogen as your storage medium.
In different phrases, you will want about 35 instances the capability of photo voltaic panels as the quantity of agency energy that you’re dedicated to offer. The explanations for the huge differential embrace: the solar doesn’t shine absolutely half the time; more often than not when the solar does shine it’s low within the sky; locations just like the UK, Germany and New York are cloudy most of the time; and there are important losses of power each in electrolyzing the water after which once more in burning the hydrogen.
Anybody and everybody ought to be at liberty to verify my arithmetic right here. I’m absolutely able to making errors. Nonetheless, a number of individuals have already checked this.
My Report then takes a stab at translating the large incremental capital value of all these photo voltaic panels into a really tough value comparability of attempting to generate the 288 MW of agency energy from photo voltaic panels and inexperienced hydrogen versus merely burning pure fuel within the plant. I received value figures for the turbine plant and the photo voltaic panels from a March 2022 report of the U.S. Power Data Company. Utilizing that knowledge:
[T]he value of the 288MW Common Electrical turbine energy plant [would be] round $305 million, and the price of the 4,704 MW of photo voltaic panels [would be] round $6.25 billion.
For those who wanted the 9,936 MW of photo voltaic panels since you stay in a cloudy space, the $6.25 billion would turn out to be about $13 billion.
My very tough calculation within the Report, with the 20% photo voltaic capability issue assumption, is that electrical energy from photo voltaic panels plus inexperienced hydrogen storage would begin at someplace within the vary of 5 to 10 instances dearer than electrical energy from simply burning the pure fuel. On the 10% photo voltaic capability issue assumption, make that 10 to twenty instances dearer.
And in spite of everything of this we nonetheless haven’t gotten to the very substantial further engineering challenges of working with the very gentle, explosive hydrogen fuel. Just a few examples from the Report:
- Making sufficient inexperienced hydrogen to energy the world means electrolysing the ocean. Contemporary water is of restricted provide, and is especially scarce in the very best locations for solar energy, specifically deserts. While you electrolyse the ocean, you electrolyse not solely the water, but additionally the salt, which then creates massive quantities of extremely poisonous chlorine, which have to be neutralised and disposed of. Alternatively, you’ll be able to desalinise the seawater previous to electrolysis, which might require but further enter of power. There are individuals engaged on fixing these issues, however options are far off and could possibly be very expensive.
- Hydrogen is just about 30% as power dense by quantity as pure fuel. Which means it takes about thrice the pipeline capability to move the identical power content material of hydrogen as of pure fuel. Alternatively, you’ll be able to compress the hydrogen, however that will even be an extra and doubtlessly massive value.
- Hydrogen is far more troublesome to move and deal with than pure fuel. Use of the present pure fuel pipeline infrastructure for hydrogen may be very problematic, as a result of many current fuel pipelines are product of metal, and hydrogen causes metal to crack. The next leaks can result in explosions.
Learn the complete article right here.
