Gasification of Fossil Fuels

Fossil fuels have been the source of energy for the industrial revolution and continue to be at the center of global energy supply with electrical and thermal energy. Fossil fuels like anthracite, lignite, coal coke or brown-coal briquettes have also been used in gas-generation through gasification. And just as is the case with biomass the chemical composition of coal types does differ a lot.

The following table shows three simple examples of coal characteristics:

 

TestresultsWest-German
Brown-Coal
Coal CokeBrown Coal Briquetts
Heating Value

19,2 MJ/kg

27,5 MJ/kg

19,47 MJ/kg

Moisture

17 %

7 %

19 %

Gas CombinationCO

16,62 %

25,0 %

25,3 %

CO2

14,06 %

4,0 %

5,3 %

H2

12,56 %

3,9 %

16,95 %

CH4

1,33 %

0,11 %

2,45 %

Calorific Value
of the Gas

992 MJ/kg

860 MJ/kg

1.225 MJ/kg

 

With over 200 years of energy supply from coal it is absolute inevitable that technical innovations will lead to a long-term replacement of this source of energy. This expectation is supported by the high amount of greenhouse gases emitted when burning coal in conventional power-plants as well as the severe environmental impacts with dust and particulate matter causing SMOG and severe health issues as can currently be witnessed in China.

Yet unlike biomass and other raw-materials and residual wastes which could be used for energy production, coal does have a global logistics network which grew and got optimized by market-forces for decades. Along this a vast number of jobs has been created in coal-production, processing and logistics. Therefore an end to coal-based energy production cannot happen in one technical step since this would overwhelm the economic and moreover the social systems of societies. Therefore the first step in a future-orientated use of a fossil fuel like coal lies in the more efficient use of the feedstock. One way to achieve this is the use of coal in decentralized gasification power-plants.

 

 

 Combustion of Coal Gasification of Coal 
 Efficiency

Up to 46 percent  in the most modern centralized plants with little or no use of the thermal energy generated due to the large distances between power-plants and consumers.

Up to 90 percent of total energy efficiency because the decentralized technology with its low emisions allows for local energy production in a CHP-setting where electrical and thermal energy can be successfully sold.

 

The advantage of a concept based on a decentralized technology for energy generation from coal lies within the distribution of emissions all over the land rather than concentrating them in one single community which is then forced to carry the social and environmental costs of the energy demand by others. Moving the production of electricity and heat closer to consumers allows those to influence the volume of emissions in their region by saving energy and investing into energy-efficiency themselves. With huge centralized power-plants energy-consumers lose all power in the market for clean air leading to a loss of incentive to invest in energy efficiency.

Changing energy production to a localized concept where energy-generation and the emissions caused by it are moved closer to energy-consumers must take into account that globally the acceptance of energy from coal is actually in decline. This is largely due to the fact that energy from coal is associated with huge, old and outdated, centralized power-plants which are highly inefficient and are being seen as a major cause of climate change, the emission of greenhouse-gases and air-pollution. The much lower emissions and much lower environmental impacts when using coal with the more efficient gasification technology are being ignored by interest groups lobbying against the use of coal, politicians and the population in general.

As a sad consequence of interest group behavior and the lack of technical and chemical understanding in the general public the more climate-friendly and more environmentally friendly use of coal as a source of electrical and thermal energy via gasification technology is so far being halted. As a result of this blockade on all levels, targets for the reduction of greenhouse gas emissions as well as targets for cleaner air are being missed out at the costs of all people.

But it is exactly this use of coal for energy supply within gasification which will pave the way away from coal-based energy supply to an all renewable-energy based economy, which will provide businesses and private households with electrical and thermal energy. This transition can be majorly supported by gasification technology. In a first step gas-generators for the gasification of coal would form the heart of a fossil-fuel gasification plant which is locally based, close to energy consumes.

Such a plant from A.H.T. Progas can be refurbished to work with biomass or other locally available raw materials or residual wastes within a revision process which takes about eight weeks. While large centralized coal-fired power-plants in Europe nowadays need over 40 years until the investments have paid-off, decentralized gasification plants can reach this point within ten years. This would allow financing the refurbishment from the cash-flow generated by coal-gasification once the supply-logistics for local or regional feedstock have been established.

These very logistics are the key-disadvantage renewable energy sources have when competing against coal as a fuel. This disadvantage can only be overcome in a long-term strategic approach which takes time to establish especially since this supply should be sustainable. Until this supply has been established the gasification of coal for the production of electricity and heat will be already one step ahead towards better climate-protection through the reduction of greenhouse-gas emissions as well as local air pollutants. 

However if prejudices continue to be the fertile soil on which the demand for a radical end to coal-based energy is growing then the goals for climate protection and the reduction of greenhouse-gas emissions will be further at risk. As long as there are no working alternatives to gasification in the supply of base-load as well as peak-load energy, the old outdated coal-power-plants will stay connected to the grid keeping air pollution and greenhouse-gas emissions at the current high levels because new large coal-fired power-plants cannot be built against local will or economic reasoning.

Coal as a fossil fuel is not unlimited in supply and will come to a foreseeable end through technological innovation. This switch away from this high-pollution, climate-endangering energy source is set to fail if special interest groups fighting coal-based energy in general, political populism and local people initiatives (against bearing their fair share of the burden of their energy consumption) prevent the only technology – the gasification technology – from making the first step to a sustainable energy future by using energy generated from the gasification of coal in a more efficient, more environmentally friendly and less climate-endangering way.