By:Lars Engvik
Why is energy knowledge important?
A lot of the public debate is centred around energy, energy availability, energy efficiency and the consequences of using energy.
Energy availability has for decades been a key issue.
The debate occasionally reaches very high “temperatures”.
This only confirms that energy is something that concerns many people and that there sometimes are strong and often biased opinions being communicated.
This is in particular visible in various social media.
Even wars have taken place to secure access to and control of energy sources.
Establishing diversity in respect of energy provision and finding alternative energy sources has, at least since the 1970s been high on the agenda.
The focus on alternative energy sources is still there, but nowadays the concern is much more towards environmental issues, such as avoiding release of greenhouse gases and other harmful substances.
There is an ongoing debate, if and how society could move away from extracting and using fossil fuels to provide energy.
Since this is a global debate, signified by many different agendas and preferences it is not always easy to take a stand on all the matters concerned.
Therefore it might be wise and also useful to have basic knowledge and obtaining some unbiased facts related to energy matters, enabling formation of our own opinions and to be able to recognise the most colored statements
I fully appreciate that we as humans do have different preferences and that everybody will not have the same opinion on what is the best way of resolving important matters.
However I strongly believe in using factual information as a basis of forming our opinions and reaching our conclusions, whatever they might be.
Here are some simple examples of situations where possessing some basic knowledge could turn out helpful to avoid being fooled by somebody promoting strongly their own views without being too concerned about the facts:
1. Somebody claims that Hydrogen means zero emission.
Then it is good to know that the only emissions caused by using Hydrogen to produce electricity in a fuel cell is water.
However hydrogen is in most cases generated from steam reforming of methane, which is causing a considerable amount of CO2.
If Carbon Capture and Storage (CCS) is not used the CO2 is released into the atmosphere.
Hydrogen could also be generated through water electrolysis. The amount of hydrogen produced by this method is steadily increasing.
Water electrolysis uses a large amount of electricity for producing hydrogen, around 50 – 65 Kwh/Kg H2 and if clean, potable water is used the only byproduct is oxygen.
Since a large amount of electrical power is necessary, the environmental impact of this method is largely depending on how the electricity used, is generated (the actual energy mix).
2. Somebody claims that the use of fossil fuel is low cost and efficient.
Then it might be good to know that the cost issue is very much depending on where you are, local policies, taxes and tarifs, refining capacity and of course the current price levels of natural gas and crude oil and the carbon emission fees and taxes.
In general it is true that most of the time fossil fuels have been very cost competitive compared to other energy sources or energy carriers.
It is also worth noting that the energy efficiency when using fossil fuels is not always very high.
A modern dual cycle natural gas fuelled power plant (also utilising the heat from the exhaust for generating power) could reach an efficiency close to 60%.
On the other side of the scale the energy efficiency of an internal combustion engine fuelled by gasoline in many cases would be as low as 25% – 30%. The efficiency of a diesel engine would be a little higher 35% – 50%.
Read more about gas turbines here
Read more about internal combustion engines here
3. Somebody claims that biofuel is emission free.
Then it is good to know that combustion of biofuels emits CO2 and depending on the fuel and the use, may also emit other harmful substances such as carbon particulates, carbon monoxide and NOx (various nitrous gases).
However, combustion of biofuel is considered less harmful to the environment than combustion of fossil fuels.
The amount of carbon dioxide emitted when biofuel is combusted is regarded similar to the amount of carbon dioxide that already has been captured and stored through the photosynthesis and growth of the plants, provided the biofuel is produced from trees or other plant material.
Further it is considered that a similar amount of the carbon dioxide emitted when biomass or biofuel is combusted would have been released anyway, had the biomass undergone natural decomposition.
Also the emissions of carbon particulates, carbon monoxide, NOx and sulphur compounds in some cases may be reduced compared to fossil fuels.
These are the main reasons why biofuel often is regarded as carbon or climate neutral.
Since the use of biofuel is considered replacing some of the fossil fuel that otherwise would have been used it is sometimes even considered as emission negative.
Biofuel is made from biomass. Examples of biomass used for biofuel production would include:
- Wood and forestry residues
- Various food and animal feed crops
- Cereal straw
- Oil palms
- Algae
- Vegetable oils, fish oils and animal fats.
Be aware that biofuel is not always regarded as more environmental friendly than fossil fuels.
The main reason for this is that using (food) crops for fuel production may indirectly or directly lead to deforestation and drainage of marshlands, which in many cases would cause increased emissions of greenhouse gases into the atmosphere.
Whether land needs to be cleared to replace “lost” food or animal feed crop (indirect) or it is needed to actually make space for the new crops meant for biomass production itself (direct), such land use change could and in many cases will be the reason for increased greenhouse gas emissions into the atmosphere.
This would of course be the case for whatever reason deforestation and drainage is done and not only when this is done as a consequence of biofuel production.
This effect is called, either Indirect Land Use Change, ILUC. or if new land areas needs to be cultivated as a direct consequence of the biomass production, Direct Land Use Change, DLUC.
This is less of a problem with biogas since Biogas is normally generated through biological digestion of various organic materials from animal farming, sewage and landfills.