The Renewable Gas Ask : Part F

Synthetic and renewable fuels are likely to be able to answer both climate change and air pollution concerns, to a greater or lesser extent.

Which gases are best to use for which purpose ? Gases good for combustion release a lot of heat when oxidised. Gases good for trade by liquefaction have boiling points closer to 0° C than further away from it. Simple covalently-bound molecules are most appropriate for reactor chemistry – where transformational reactions are fostered.

Which liquids are best for which application ? Liquids for cleaner combustion are likely to be oxygenate – have oxygen in their formula; and when their thermochemical properties suit the engines they are to be burned in.

Here is a first pass at summarising some of the molecules being investigated – molecules that can be synthesised from basic input chemical feedstocks.


Table : A Selection of Compounds in Industrial Gas and Fuels Chemistry

Note : STP = Standard Temperature and Pressure (20° C to 25° C, at 1 atmosphere of pressure).

Note : DME is here used for Dimethyl ether, and not Dimethoxyethane.

Note : Oxymethylene Dimethyl Ethers are also known as PODE, Polyoxymethylene dimethyl ethers; POMDME or OMDME.

CompoundFormula Boiling Point
(° C)
State (STP)Use
HydrogenH2 -252.87GasFuel, Feedstock
WaterH2O +100LiquidFeedstock
OxygenO2 -182.95GasCombustion
Carbon monoxideCO -191.5GasFuel, Feedstock
Carbon dioxideCO2 -57GasExhaust, Feedstock
AmmoniaNH3 -33.34GasProduct
NitrogenN2 -195.8GasFeedstock
Nitrous oxideN2O -88.46GasExhaust
Nitrogen dioxideNO2 +21.15Liquid/GasExhaust
Nitric oxide, nitrogen monoxideNO -152GasExhaust
MethaneCH4 -161.50GasFuel, Feedstock
EthaneC2H6; H3C-CH3 -88.5GasFuel, Feedstock
PropaneC3H8; H3C-CH2-CH3 -42GasFuel, Feedstock
Butane, n-ButaneC4H10; H3C-CH2-CH2-CH3 -0.5GasFuel, Feedstock
isoButane, 2-MethylpropaneC4H10; H3C-CH(-CH3)-CH3 -11.7GasFuel, Feedstock
Ethene, EthyleneC2H4; H2C=CH2 -103.7GasFeedstock
Propene, Propylene, Methyl ethyleneC3H6; H2C=CH(-CH3) -185.2GasFeedstock
Butene, Butylene, as alpha-ButyleneC4H8; H2C=CH(-CH2CH3) -6.3GasFeedstock
Butene, Butylene, as cis-beta-ButyleneC4H8; H3C-CH=(CH(-CH3)) +2.25, +3.72…GasFeedstock
Butene, Butylene, as trans-beta-ButyleneC4H8; H3C-CH=(CH(-CH3)) +2.25, +3.73…GasFeedstock
Butene, Butylene, as isoButyleneC4H8; H2C=C(-CH3)CH3 -6.9GasFeedstock
Methanol, MeOHCH3OH; H3C-OH +64.7LiquidFuel, Feedstock
Ethanol, EtOHC2H6O; H3C-CH2-OH +78.24LiquidFuel, Feedstock
Propanol, 1-PropanolC3H8O; H3C-CH2-CH2-OH +97 to +98LiquidFuel, Feedstock
isoPropanol, isoPropyl Alcohol, IPA, 2-PropanolC3H8O; H3C-CH(-OH)-CH3 82.6LiquidFuel, Feedstock
Butanol, n-Butanol, 1-Butanol, butan-1-olC4H9OH; H3C-CH2-CH2-CH2-OH +117.6LiquidFuel, Feedstock
sec-Butanol, 2-Butanol, butan-2-olC4H9OH; H3C-CH2-CH(-OH)-CH3 +98 to +100LiquidFuel, Feedstock
isoButanol, 2-methylpropan-1-olC4H9OH; H3C-CH(-CH3)-CH2-OH +107.89LiquidFuel, Feedstock
tert-Butanol, 2-methylpropan-2-olC4H10O; H3C-CH3(-CH3)-OH +82.3LiquidFuel, Feedstock
Methanal, FormaldehydeCH2O; H2C=O +64.7LiquidFeedstock
Dimethyl ether, Methoxymethane, DME, PODE-0, OMDME-0C2H6O; H3C-O-CH3 -24GasFuel, Feedstock
Oxymethylene Dimethyl Ether 1, OME-1, Methylal, Dimethoxymethane,
PODE-1, OMDME-1, DMM
C3H8O2; H3C-O-CH2-O-CH3 +42, +45.2LiquidFuel, Feedstock
Oxymethylene Dimethyl Ether 2, OME-2, PODE-2, OMDME-2C4H10O3; H3C-O-CH2-O-CH2-O-CH3 +105LiquidFuel
Oxymethylene Dimethyl Ether 3, OME-3, PODE-3, OMDME-3C5H12O4; H3C-O-CH2-O-CH2-O-CH2-O-CH3 +156LiquidFuel
Oxymethylene Dimethyl Ether 4, OME-4, PODE-4, OMDME-4C6H14O5; H3C-O-CH2-O-CH2-O-CH2-O-CH2-O-CH3 +202LiquidFuel
Oxymethylene Dimethyl Ether 5, OME-5, PODE-5, OMDME-5C7H16O6; H3C-O-CH2-O-CH2-O-CH2-O-CH2-O-CH2-O-CH3 +242LiquidFuel
TrioxaneC3H6O3; -CH2-O-CH2-O-CH2-O- +114.5LiquidFeedstock
Diethyl ether, Ether, Ethoxyethane, DEE, OMDEE-0C4H10O; H3C-H2C-O-CH2-CH3 +35LiquidFuel
Oxymethylene Diethyl Ether 1, Diethoxymethane,
Ethylal, DEM, OMDEE-1
C5H12O2; H3C-H2C-O-CH2-O-CH2-CH3 +88LiquidFuel, Feedstock
Oxymethylene Diethyl Ether 2, OMDEE-2C6H14O3; H3C-H2C-O-CH2-O-CH2-O-CH2-CH3 +140LiquidFuel
Oxymethylene Diethyl Ether 3, OMDEE-3C7H16O4; H3C-H2C-O-CH2-O-CH2-O-CH2-O-CH2-CH3 +185LiquidFuel
Oxymethylene Diethyl Ether 4, OMDEE-4C8H18O5; H3C-H2C-O-CH2-O-CH2-O-CH2-O-CH2-O-CH2-CH3 +225LiquidFuel
Dibutyl ether, DBEC8H18O; H3C-H2C-H2C-H2C-O-CH2-CH2-CH2-CH3 +140.8LiquidFuel

The Renewable Gas Ask : Part E

Previously, I have been considering what groups of economic actors in what sectors could be influential in calling for the development of Renewable Gas – low net carbon emissions gases, used as energy fuels and chemical feedstocks, thermochemically or biologically synthesised from renewable electricity, water and biomass :-

https://www.joabbess.com/2020/01/08/the-renewable-gas-ask-part-a/
https://www.joabbess.com/2020/01/09/the-renewable-gas-ask-part-b/
https://www.joabbess.com/2020/01/10/the-renewable-gas-ask-part-c/
https://www.joabbess.com/2020/01/11/the-renewable-gas-ask-part-d/

I need to go back a little bit to add some extra thoughts, so these will be paragraphs marked with “Continued”.

1.   The World of Chemical Engineering (Continued)

One key sector in the universe of molecule management is plastics, which are now so essential in trade, commerce and manufacturing. That there is so much ethane coming on-stream from the United States hydraulic fracturing oil rush in the form of high levels of NGLs (Natural Gas Liquids) is good news for petrochemical firms big in polymers. Yet, this bounty is unlikely to continue, so what should happen when fracking uncertainties start to mount ?

Will Big Chemistry start to ask for Renewable Gas ? And will they ask for Renewable Gas from themselves ? This would make sense, as the petrochemical industry will have need of a range of light organic and inorganic molecules, even if these are not being supplied as by-products from the mining and refining of fossil fuels.

Petrochemical plants need to to be able to ride changes in the composition of a barrel of oil, and the “balance of plant” in oil refineries. Here, there would be a huge sink for any Renewable Hydrogen that could be made by any sector. Hydrogen is necessary to synthesise a range of chemistry, for example the production of agricultural chemicals, such as ammonia. If the source of much of the world’s hydrogen continues to be fossil fuels, for example, through the gasification of coals and the steam reforming of the methane from Natural Gas, then Big Chemistry will live with increasing uncertainties about the guarantees of supply.

The agricultural sector could step in themselves and ask for Renewable Gas to underpin their supplies of fertiliser, pesticides and other chemicals feeding the world.

5.   Car Manufacturers (Continued)
6.   Utility Vehicle Manufacturers (Continued)
7.   Freight Vehicle Manufacturers (Continued)

It is anticipated to take a considerable amount of time to replace the current global fleet of internal combustion engine drive (ICE) vehicles, whether car (automobile), light duty vans or heavy duty, heavy goods vehicle trucks/lorries.

Vehicle manufacturing companies have divergent strategies. Many of them have launched electric-only ranges. Some of those serving the freight/haulage markets have brought out gas drive options, intended to be run on CNG, Compressed Natural Gas; in advance of electric models, perhaps because of concerns about power-to-weight ratios, or levels of confidence in batteries. Some automakers have brought out hydrogen fuel cells models, but this only makes sense where there is hydrogen distribution network for fuelling stations. By contrast, power and Natural Gas are distributed widely.

There is a lot of advertising for electric or electric-hybrid vehicles, but this will only impact on the sales of new vehicles – a vast majority of the global “fleet” will remain fuelled by liquids. Whilst sales of electric models pick up, companies will still be selling new ICE cars, vans and so on. As demand for electric models rises, there will likely be situations where production and supply cannot keep up. These imbalances will lead to stress in highly competitive markets.

This dynamic could make the car companies seek to create a levelising factor, to gain back control of sales densities by appealing to oil refiners to bring the net carbon in fuels down. Then customers could have the option to buy combustion engine models, but use “alternative”, “advanced” fuels, which have far lower net carbon emissions.

From the point of view of the economists, this would be preferable : vehicles running on new low carbon fuels would be tested in the market, competing against models driven on electric drive (and hybridised). And in addition, hybrids could use the new fuels too, and become 100% low carbon.

Running two streams of low-to-zero carbon energy to vehicles will also help to document the relative efficiency of power versus low carbon liquid fuels in the whole system.

The theoretical well-to-wheels energy efficiency of electric drive vehicles is significantly better than liquid fuels combustion drive vehicles; however, there is a need to buffer the electricity – running power to filling stations is not optimal. The energy from the electricity should be stored first, awaiting filling demand.

Synthesised gas could act as the buffer to power. This low carbon gas would be stored centrally, and as required, run to the filling stations by pipeline network. Because the gas is packed in the line, it will not be wasted. Fuel cells at the filling stations would convert the gas back to power, as and when needed.

Whilst low mileage/kilometrage electric vehicles might be the right answer for urban environments, particularly from the point of view of air quality, the question of freight – the haulage of food, resources and goods – is one that may be answered by gas drive vehicles rather than electric vehicles. Having a tankable fuel eliminates range anxiety, and means that heavy batteries do not need to be carried along with the merchandise. Any light duty vehicle too that needs to run long distances might be better propelled by liquid or gas fuels – another possible market for Renewable Gas and the liquid fuels that can be synthesised from it.

Besides the carmakers, and the light and heavy goods vehicle manufacturers, the road hauliers as trade bodies might put up the ask for Renewable Gas in the form of Renewable Fuels; traditionally there have been strong trade associations between fuel refiners, fuel distributors, filling station networks and those who run haulage.

11.   The Fossil Oil and Gas Producers

Strange as it may sound, the companies that produce crude petroleum oil and Natural Gas might themselves start to call for Renewable Gas. This would partly be because they are strongly vertically integrated enterprises, with refineries and they also often do distribution of fuels for sale.

Key oil majors have for some time been strategising about becoming gas majors – focussing their business plans on gas instead of oil. If it is true, that Peak Demand for Oil has been reached, oil majors, now gas majors, might begin to consider what would happen when there is a Peak in Demand for Gas, too; if consumers started to desert fossil hydrocarbons and head towards Renewable Electricity for their energy.

The ex-oil, now-gas majors would therefore need to have a plan to keep up their levels of income, and keep their shareholders happy. A good way to do that would be to enter into the field of providing energy services, and making and providing low carbon electricity – some companies such as Shell have been very overt about doing this.

If these companies go the next logical step and also get into energy storage, the wheel will have come full circle, as power storage is perhaps best as synthetic gas production and storage.

And so, Renewable Gas would be a strategy for ex-oil, now-gas majors to keep from contracting, to keep up sales of energy, whilst dropping the carbon from it.

Renewable Gas : The Energy Calculus Caucus

The major oil and gas companies, along with a range of other organisations and agencies, have ongoing energy modelling projects, building scenarios to paint projections in energy, technology and the wider economy.

Table : A Selection of Organisations Working On Energy Models, Data, Statistics and Projections

Inputs to the world’s energy systems are usually considered immutable – wood is the principal biomass; crude petroleum oil is going to remain the primary feedstock for liquid hydrocarbon fuels; Natural Gas is the majority source of energy gases; and solid fuels are considered to be fossil coal-derived.

The projections into the future are mostly done on a “lasts until” basis, that is there are underlying assumptions that all the fossil fuels that can be economically mined will be, right up to steep depletion, and that nothing can substitute for them as primary energy resources.

Alternative energy resources are considered entirely separately from fossil fuels, and are only projected to form thin slivers of contribution on energy projection graphs. There is an unwritten code that alternative primary energy resources must be forced to compete economically, and that deployments of alternative primary energy will only be commissioned if scarcity is experienced elsewhere. Fossil fuels are thought to prop up the energy system, and be dependable; to remain cost-efficient and cost-competitive under any conditions. We will only build renewable energy production when we need it, being the major thread.

Where admissions are made, for example, where modelling suggests that depletion, economic pressure and policy could affect the levels of fossil fuels mined and brought into the economy, there is a default view generally that this might stimulate alternatives, but from a very low starting point, and with marginal growth.

Emerging technologies and biomass-based feeds into the fossil fuel refining and distribution systems are considered opportunistic, blighted by cost and reliability issues, and are expected to suffer negative economic stimulus, to such an extent that they are not expected to make much more than a sliver of contribution; although in some cases they are trusted to “take up the slack” where fossil fuels fail.

In such projections, where fossil fuels can and will speak for most of the world’s energy demand, without significant economic and political change, the necessary rate of new technology deployment is fractional.

This paradigm is expressed in a number of different ways by different actors, and creates an impression that fossil fuels are failsafe, and naturally dominant. Fossil fuels and alternative energy resources are considered to be chalk and cheese – not of a kind. This belies the opportunities for substitution of fossil fuel feedstocks by biomass-, water- and green electricity-sourced streams.

The major failing in many energy models is that no consideration is given to active transition – that is, how to turn around the downward trendlines of fossil fuel production and sales into upwards shares of alternative fuels production and sales, through molecular and electron substitution from renewable sources.

If alternative technologies and fuels were actively encouraged to displace fossil fuels, according to core strategy within the energy system, this would cause greater levels of deployment, and so accelerate transition. Alternative resources would constitute a larger slice of the overall total, and show what higher decarbonisation potentials exist.

For example, every extra modelling for hydrogen use, for example, the hydrogen increasingly used for in liquid fuels refining and synthesis, written as renewable hydrogen production and use, which will necessitate higher levels of renewable elecricity production/generation and use.

The production of liquid hydrocarbon fuels and chemical feedstocks will be needed for decades to come, but these don’t need to come from crude petroleum oil, Natural Gas and coal. With synthesis, the source of the hydrogen and carbon (and oxygen) landing in the liquid fuel products is not relevant, except it should conform to the requirements of protecting a liveable climate.

With liquid fuel synthesis, we can rest from thinking about complex hydrocarbon primary resources, stop looking at the molecular level of organisation, and start to look at the individual streams of elements : where does the hydrogen flow from ? Where, the carbon ?

With synthesis, the source of the hydrogen and carbon (and oxygen) coming into the energy system is not relevant. What matters is how many of the H, C (and O) are coming from renewable resources. We “3D print” the molecules we need, and we don’t need to dispose of the carbon, oxygen (and sulfur) we don’t use.

The biggest problem is where we get the Young Carbon from : Renewable Carbon needed for liquid fuels needs to come from recently-living biological organisms in order not to tamper with the global long-term carbon cycle.

In systems for Renewable Gas-to-Power-to-Gas, renewable electricity is used to make gas for long-term storage, offsetting electricity generation to times when the wind is not blowing and the sun is not shining, and it’s cold. These systems can be centralised, and contained, so the carbon used in the system to lock hydrogen into methane for long-term energy storage, never needs to leave the plant. However, for producing liquid transport fuels, carbon will flow through the supply chain, and so needs to be sourced from renewable, young resources.

With time, it is likely that transport options will mostly become electric, and quite often public, in urban settlements. Freight transportation, and industrial and agricultural machinery fuelling will mostly likely be a combination of light gaseous fuels and electric power. But that time is more than a few decades away, as it will take that long to replace all the vehicles and fuel supply systems. In the meantime, we need renewable liquid fuels.

Energy modelling does not presently include much in the way of molecular and electronic substitution for fossil fuel primary energy resources; is not conscious of the multiplier effect of going beyond the small percentages of substitution by first/second generation biofuels and biomethane.

Since we need to produce liquid fuels for several decades to come – fuels that automatically need to have higher boiling points, and so need to have carbon in them – in order to see the possible speed of the low carbon transition, we need to model every way that fossil carbon and fossil hydrogen can be swapped out for Renewable Carbon and Renewable Hydrogen.