Renewable Gas : Big Problems in Energy Transition

There are a number of difficult problems in the transition to low carbon energy. One of the early barriers to change was denial of the science and evidence of dangerous global warming. And when that stance crumpled, the next hurdle was a denial of the responsibility to act in a short timeframe. Energy enterprises appeared to think that low carbon energy transition would consist of familiar low pace investment and operations lifecycles, simply substituting high carbon investments for low carbon investments at the normal end of plant or equipment life.

And then there was the postulated problem with the economics of new technologies, where companies wanted to attract tax breaks, subsidies and grants in order to underwrite their low carbon transition, rather than spending their own capital. All the while, companies were lobbying for their preferred solutions, such as Carbon Capture and Storage, that would entail less of their own expenditure, change less of their normal business practices, and supply chains, and justify government support.

Thankfully, pragmatism seems to have trumped dogmatism, and there is a lot of movement in the energy sector, witnessed by massive additions in wind power and solar power.

However, there are two really weighty and thorny problems with energy transition that have very long lead times for resolution, and need a strong focus. The first of these is inefficiency in energy conversion, particularly centralised electrical power generation through combustion. The second is the inertia in the transition to low carbon transport and transportation.

1.   Combustion is Inefficient

Combustion, or oxidation of fuels, particularly at lower temperatures, where heat is not captured for further use, is very inefficient.

Much electricity production is still through the burning of fuels in centralised power plants, where much of the input energy is lost to unusable heat. Losses are very significant, and form a substantial wedge of energy flows.

For example data, taking the IEA Global Energy flow Sankey Diagram :-

 Energy input to Power stations

   Hydro input to power stations   14697 PJ
   Nuclear input to power stations   28783 PJ
   Solar/tide/wind   5830 PJ
   Geothermal   3027 PJ
   Biofuels and waste   8391 PJ
   Natural gas   52907 PJ
   Oil   1703 PJ
   Oil products   7733 PJ
   Coal to power stations =   145441 – 46051 = 99390 PJ

   Calculated Total =    222461 PJ
   Reported Total =    222461 PJ

 Energy output from Power stations

   Electricity   92182 PJ
   Heat   14287 PJ
   Losses (such as heat that cannot be used)   116060 PJ

   Calculated Total =    222529 PJ
   Difference between output and input energy =    68 PJ

The losses from electricity generation mean that efficiency is :-

Useful energy output divided by total input energy = 106479 / 222461 = 47.86 %

Although power station fuels such as coal and Natural Gas are dirt cheap at present, this situation might not continue, and within a couple of decades the inefficiencies of present day electricity production could place significant cost burden on the economy.

A major goal would therefore usefully be to ramp up the amount of renewable electricity provided to the system, to drastically reduce energy losses. In addition to the efficiencies drawn from not burning anything, wind power and solar power can offset centralised generation by being used close to where they are produced.

The variability of wind power and solar power needs addressing, but thankfully, Renewable Gas technologies can step into the breach here : using spare renewable power to produce Renewable Hydrogen and Renewable Methane, which can be stored, and later on, substitute for Natural Gas in backup power generation when the wind calms and the sun sets.

2.   Transport Slow To Transition

Transport requires a large segment of the energy in the global economy : according to the IEA World Balance 2017 figures, the energy wasted in power generation is of a similar order of magnitude to the energy value of refined petroleum oil products entering the economy as fuels for transport = 108376 PJ.

Most energy projections suggest that the Global South (or East) countries will continue to increase their use of refined petroleum liquid transport fuels for the next few decades. Even though the Global North (or West) will reduce demand growth, the total liquid fuels required is expected to stay roughly level out to 2040 or even 2050.

Barring a genuine revolution in the systems for vehicle manufacture, sales and recycling, there will continue to be high levels of ICE internal combustion energy drive vehicles on the roads compared to electric vehicles and hybrids, and other alternative drive models. Despite the fact that a significant proportion of car advertisements are now for electric and hybrid vehicles, these form only a few percent of current sales.

Patterns of vehicle turnover – replacement unlikely to be done simply to “go electric” – may change. If the average lifespan of vehicles increases, transition will take even longer.

Transport is proving slow in transition, and there are few genuine disruptions that can be envisaged to speed this up.

This means that liquid transport fuels will continue to be needed for many decades to come. The global economy is locked in to vehicles using liquid fuels, and crude petroleum oil production and refining companies feel secure enough about future demand to cast long term business plans.

But there remains the need to decarbonise this significant sector. And apart from planting trees, there is no practical way to implement Carbon Capture and Storage for transport emissions.

And this means that there is really only one sensible proposal for decarbonising transport, and that is to decarbonise the fuels.

Renewable Fuels development therefore becomes a major goal.

Here again, Renewable Gas comes to the rescue, as many chemical engineering routes to Renewable Fuels can use Renewable Hydrogen and Renewable Methane.

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