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  • Writer's pictureSol J

Debunking the hydrogen myth

Hydrogen infrastructure provides an excellent case example that explains why we've got it so wrong and how we should be viewing energy movement within our global energy supply chains in a comprehensive, systemic fashion.



Hydrogen has been hailed by politicians and clean-and-greeners as the solution to all our fuel supply problems. But it's not going to cut it.

"A lie gets halfway around the world before the truth has a chance to get its pants on." - Winston Churchill

Hydrogen, the fuel of the future. High tech, leaves only water as emissions and able to be made using only carbon neutral renewable energy and water. Looks good, sounds good, plenty of photo opportunities for everyone and a new multi billion dollar industry with jobs all round. Problem solved, now we can get back to the media team and campaigning for our next role in office.


A politician's dream.


Unfortunately, the spin doctors forgot to call in the scientists first. Yes, those annoying guys in the white coats who always show up wearing socks and sandals and ruining the optics for everyone. No wonder they never get invited. But had they been, they would probably have told a whole bunch of things decision-makers in government and business didn't really want to hear. There are a few reasons for this.


The first one is that basic science can be very difficult for many decision makers to grasp. In the main it's not part of their background. Then, the idea that they might have to balance a reasoned debate grates against the general modality of politics which by it's very nature is prepositioned and adversarial, rather than openly questioning. The third is that to properly understand whether an energy technology actually provides any benefit, we require a view of the entire supply chain and dozens of externalities. This type of systems thinking does not come naturally to many people and even to scientists. It may only come with practice and contact with several different fields.


So usually what results is that when scientists explain why something won't work, expecting that deductive reasoning will prevail they end up walking away bewildered when their advice wasn't heeded. It's a cognitive problem and it's pervasive throughout all forms of governance. Usually scientists start at the wrong end, trying to explain the science rather than identifying the (false) assumptions of the listener before they speak. They lose the listener at the start because you can't train someone to think a certain way in a few sentences. And that's all the time you've got.


We're going to try to get to the heart of the cognitive block in the hydrogen debate, because it has important implications for the replacement of fossil fuels generally.


Combustible fuels such as petroleum, coal and gas, or biomass, are nothing more than chemical batteries. In the case of all fossil fuels, they trace their energy back to photosynthesis in prehistoric plants that captured energy from the sun. We call them fossil fuels because they were once plants and other organisms that were laid down in geological beds and compressed until they formed hydrocarbons that we presently extract as crude oil, gas or coal.


In the case of biofuels, the link back to the sun is more direct, but it is still solar radiation that was converted into high energy chemical bonds in plants, initially in the form of sugars. These chemical bonds are literally the battery that the plant uses to support its biological processes and they are partly released during the night time phases of the plant's living processes. They are digested as food by a grazing animal. They can also be extracted as sugars and oils and burned in a combustion process, say in an engine.


So in essence the industrial revolution and our modern globalised industrial world has been enabled by a huge battery of stored solar energy that is now nearly depleted, in terms of the actual energy we can extract from it.


Hydrogen is produced industrially from from fossil fuels by steam reforming of natural gas, partial oxidation of methane, coal gasification, biomass gasification, methane pyrolysis, or electrolysis of water. In the latter case, electricity is passed through water, splitting it into hydrogen and oxygen. It's a basic law of nature that energy can't be created or destroyed, only converted or moved around, so at its theoretical best we can only get out of hydrogen the same amount of energy we put into it. In practice it's much less than par. Hydrogen is nothing more than an energy storage and energy carrier means. It is not a new energy "source" in the sense that fossil fuels have been for the last few centuries. So why is hydrogen different to fossil fuels or biofuels?


What matters is "net" energy, in other words, when we put energy in, do we get back an energy profit that we can use. Early in the 20th century our total net energy from liquid fossil fuels at the well head was about 35 to 1. In other words, we would burn about about 1 barrel of oil to extract 35 barrels. One calls this the Energy Return on the Energy Investment at the production point (EROIp). By 2010 we were below 10:1. However, what matters is the net amount delivered to us when the oil industry has transported it, refined it, and transported the resulting transport fuels to the petrol stations...


We also have to take into account the energy sunk into making the oil platforms, the pipeline, the refineries, which means also accounting for the energy to mine the iron ore, the coking coal, the steel making, the making of the other metals required by the oil industry, the concrete, and the energy required by the people involved in all of this to live, which we estimate at about 2 billion people. So what matters is not just the EROIp at the well head but the EROIs for the net energy from oil that sustains the whole of society globally. Viewed this way, we estimate that the minimum EROIs for a society to sustain a reasonable standard of living under some austerity regime is 3.3 to 1.


We also estimate that EROIs went down to 1 to 1 by the late 1990s and has declined below that since. In other words, since then the whole of the oil industry, including all that is required to enable it to function, has been a net energy sink: it uses more energy than what it delivers. So, in fact the ongoing operation of the oil industry now depends on drawing energy from other sources than oil, i.e. coal, natural gas, nuclear, and even wind and solar. That is, it drains energy that otherwise would go to powering the end-users in the industrial world.


Think about that for a minute, when you fill a typical family sedan at the pump, with say, 50 litres of fuel, in fact you're pumping the equivalent of perhaps 1,000 litres of petroleum into the tank - every time. It's sobering stuff. And it's possibly even more (actually too scary to print here).


As you can see, you can never get something for nothing, just as it takes money to make money, it takes energy to get energy and it takes oil to get oil. The reason it works for traditional fuels is because there is historical energy stored in those chemical bonds and until recently we have had enough left over after we've extracted and processed it all to power our economy. But this isn't the case with hydrogen. When we produce hydrogen we are storing energy in the fuel but there was none there to start with. This is the difference - there's no way to get back more energy than we have to put in. It's Thermodynamics 101.


To make it worse, a part of what we put in gets lost when the hydrogen is produced and most of the rest of it is lost a second time when the hydrogen is burned. So when we charge the hydrogen "battery" we are throwing most of the energy away (twice), we get less out than we put in and we are going backwards.


But if we're going backwards energy-wise, where is the energy coming from that's making up the gap? Back to our example of filling the car. We saw that when we filled the car with petrol or diesel, the amount of oil that we're actually consuming behind the scenes is pretty daunting. But what's happening when we fill with hydrogen?


At present most hydrogen is produced from fossil fuels, So, the energy you get out of the hydrogen had to go through a whole bunch of steps to get to you. It took a fair bit just to process, pump and transport it. If it was produced directly by processing fossil fuels (steam reforming of natural gas, partial oxidation of methane, coal gasification, biomass gasification, methane pyrolysis), then we have added extra, large, energy costs to what we have seen above about the oil industry: hydrogen from direct processing of fossil fuels is a very large energy sink and a total loss - unviable, even setting aside the CO2 emissions incurred along that supply chain.


If the hydrogen is produced with electricity used to electrolyse water, the outcome is about the same. About 84% fossil fuels, are used to generate electrical power, incurring similar EROIs problems as for transport fuels. That is, most of the primary energy used to generate the electricity was lost as heat. Before that, there was the energy that went into building all the infrastructure (fossil fuels made up most of that gap). We estimate that the net energy, in the form of electricity, reaching the producers of hydrogen is only about 12% of the fossil-based primary energy brought into play. Then there are the losses we note earlier in producing the hydrogen, and then the losses in using it to power a vehicle.


All in all, if we get 5% net out of the primary energy involved to get from A to B we would be lucky. In other words, at best, we would not have changed anything since we estimate that 5% is the order of magnitude for the efficiency of current fossil-based transport. In fact, in many instances it could be worse.


Lets' now look at the case where hydrogen is produced using electricity generated from wind or photovoltaics, the so-called "Green Hydrogen". We face exactly the same problem. We have to take into account all the losses in the renewable infrastructure (about 80% for solar and about 65-80% for wind), shed off as heat to the environment. Then before that, there was all the energy to mine, build and install all the renewable infrastructure, again almost all covered by fossil fuels. The outcome is basically the same as for fossil fuels. At best 12% overall efficacy, mostly well below this, and in the process a large amount of CO2 emitted, throughout the mine-to-grave processes involved in building up the "renewables" capacity, operating it, maintaining it, endlessly upgrading it, recycling what can be recycled, and disposing of what can't be recycled (over a third of it all).


At every stage in the supply chain we find fossil fuels making up the gap, in transport, infrastructure, mining, maintenance - and the reason for that is simple, they are the only energy source we have that can generate a (by now small) total net energy return from all fossil fuels.


As you can see, every new "energy solution" we build that does not deliver a net return is driving fossil fuel depletion further and further, increasing emissions and wasting more precious energy reserves to deliver less energy for our survival.


More energy wasting, fancy solutions layered on top of previous energy wasting, fancy solutions are not the right answer in fact they are at the core of the problem. Each new layer or step that consumes more energy than it delivers incurs a shortfall that is being made up somewhere by the only energy source that presently delivers a net return: fossil fuels. Our focus should be on the following principles to attain energy independence:

  • Shortening energy supply chains, to minimise the energy costs of transporting energy

  • Reducing the number of steps in the energy supply chain to reduce the number of lossy processes

  • Ensuring that the usable energy we receive exceeds what we need to put in to access it. This can only be done by using, leveraging, high grade energy to access large amounts of low grade heat for uses such as cooking, baking, hot water production, air conditioning, refrigeration, and freezing

  • Looking at fuels like any other form of energy that just moves through the supply chain, in other words, in terms of flows and stores so that we think in terms of Energy Return on Energy Invested (EROI), in other words, energy efficiency

The nGeni technology applies these principles from the ground up in the following fashion:

  • Capture energy at the point of use, reducing the transport distance

  • Capture solar radiation directly as an incoming flow, rather than relying on secondary mechanisms such as wind or stored energy in chemical battery mechanisms

  • Capture solar radiation in the form of a high grade form of energy

  • Use that high grade energy only for noble uses requiring such high grades (motive power, lighting, computing, telecoms, etc.); and also

  • Use small amounts of that high grade energy to access large amounts of low grade forms for uses only requiring such low grades such as cooking, baking, hot water production, air conditioning, refrigeration, and freezing

  • Recycling heat that would otherwise be wasted so that it can be reused, again using small amounts of energy to move larger amounts of energy to where it is needed, when it is needed

  • Storing energy as high temperature heat as much as possible and only converting it into more convenient, high energy density, portable forms such as hydrogen or liquid fuels only as required

Hydrogen vehicles could still have a place in a Fourth Transition future, however the massive, centralised infrastructure that is being embarked upon to imitate our existing fuel supply chains is illusory, and if generalised would become lethal. It would be better to have small, household sized community sustainable, novel liquid fuels or hydrogen charging stations powered by solar thermal power, which would allow simple retrofitting of existing vehicles without the environmental impact of replacing an entire global fleet.


nGeni technology can enable such a transition, easily, profitably and without the ongoing environmental threat implied by existing strategies.

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