Tuesday, 15 May 2012

Farewell Fossil Fuels

Despite the frantic and sometimes violent attempts by activists to curtail or even stop the use of fossil fuels, that is, coal, oil and natural gas, the fond farewell seems to be far in the future. The activists efforts have not been in vain though as there have been enormous advances in cleaning up and reducing harmful emissions from coal fired furnaces, vehicles and so on.
The obvious affects of smog and acid rain on the population allowed clean air bills to be passed easily in many industrialised countries, but the use of fossil fuels has become so deeply entrenched in our society that the only way it will stop is when the fuels run out. For those not aware of what it was like to live in severe air pollution here is a short BBC film clip from China.

The question that is often asked is ‘Why do we have to stop using fossil fuels when they are so convenient?’. After trawling the internet for a definitive answer I realized that the answers given depended on the respondent’s politics. The main theme running through all the arguments was pollution of one kind or another. Fossil fuel pollution can occur during three phases: extraction, transport, and use/burning.
  • During extraction coal mining destroys farming land, oil-well accidents pollute the sea and gas extraction pollutes artesian fresh water sources.
  • During transport there is the problem of dust, gas explosions, and sea wrecks.
  • During usage there is the oh so familiar air pollution and the not so familiar problems associated with manufacture of oil based products.

The hardest question to answer is 'What are the alternatives to fossil fuels?'
Lets look at electric power generation first:

Nuclear energy? 
France produces 75% of its electricity from nuclear energy, but Japan, Russia and the U.S.A have had very unpleasant melt-down incidents. Nuclear energy would be the best type of baseline generation, but the number of nuclear power stations being decommissioned in the world seems to say loudly 'Not in my backyard!'

There are many successful dams in the world, but a reluctance by people to build new dams to stop the flooding of arable land and other environmental issues, not to mention squabbles over water rights. Unfortunately it doesn't always rain in the dams catchment area. The general opinion is no dams in my backyard!

Tidal energy? 
This was once seen as the Moons gift to mankind, but seems to have lost traction over the years probably because of the high cost, high maintenance, environmental issues and objections from people that rely on the sea for a living. It is also unsuitable for baseline generation. 

Solar panels?  
These are often seen as a quick and easy way for energy companies and governments to pay lip service to renewable energy requirements placed upon them. The reality is that solar panels cannot compete with existing energy supplies without large subsidies and are unsuitable for baseline generation. The obvious use for solar panels is for small applications where it is not possible/economical to provide any other power source, or, make a statement.

Wind turbines? 
Wind turbines seem to be the flavour of the decade, with over forty manufacturers in the market. Competition is quite brisk at the moment but the cost at the date of writing is still stated to be about $1.36 million per megawatt. Unfortunately the wind doesn't always blow when you need it, or it blows too much. The pros and cons of wind turbines are widely publicised, but many see them as the only viable renewable energy source and have staked their reputations on buying them.

Geothermal energy?
Geothermal energy supplies more than 10,000 MW to 24 countries worldwide and now produces enough electricity to meet the needs of 60 million people. In addition to large power generation, geothermal is also used for direct use purposes worldwide. In 2005, 72 countries reported using geothermal energy for direct heating, providing more than 16,000 MW of geothermal energy. Geothermal energy is used directly for a variety of purposes, including space heating, snow melting, aquaculture, greenhouse production, and more. There are environmental and land stability issues associated with extracting thermal energy, plus the possibility of triggering earthquakes. The capacity of each geothermal well is not unlimited and care must be taken in not over-extracting, unfortunately there are some very bad and unsustainable thermal extraction methods where the operator seems to be driven on short term bonuses rather than long term income.

The next biggest polluter is the internal combustion engine (ICE), the successor to the steam engine. What alternatives are available here. 

Electric Engines?
The electric engine seems to be the successor to the ICE at least for the city commuter, and China is now producing thousands of electric bicycles for mass suburban personal transport. Electric cars are now just as sporty as the ICE variety and actually have more impressive acceleration, but, only a range of about 140km with the current batteries. The most efficient battery at the moment is the lithium ion battery, but there are hopes to produce a much cheaper and greater capacity sodium ion battery in the near future. Because the battery still has to be charged it could be said that the pollution problem has been shifted from one place to another, but that's another story.

Ethanol Biofuel?
Ethanol is seen as the most favourable replacement for fossil fuels and many countries now mandate 20% of ethanol in non-diesel motor fuels. The idea is not new and I can remember 50 years ago oil companies promoting ethanol mixtures as being a big improvement (DISCOL). The most efficient way of producing ethanol is said to be sugar cane, as the crushed cane is used to fuel the boilers. There has been world over-production of sugar in the past, but now any excess can be used to make bio-fuels instead of rum.

Diesel engines can run on almost anything that will burn, and the larger the engine the more its fuel looks like tar. Bunkering oil for ships is so thick that it often has to be warmed up before it will flow. Before heavy mechanisation took over, many farmers grew oil producing trees such as olives to keep the farm tractor going. There are many grades and types of bio-diesel but high performance engines generally use fuel made by chemically reacting lipids (re-cycled cooking oil and tallow) with ethanol and producing a mixture of 5% to 20% with petro-diesel. Most diesel engines have to be modified to use 100% vegetable oil. Many countries are now mandating the use of bio-diesel petro-diesel mixtures.

Like diesel engines, jet engines can run on almost anything that can burn, even powdered coal emulsified in water. High performance jet engines are tuned for a specific fuel, usually aviation kerosene. Tests are currently being undertaken with commercial airlines with bio-jet fuels, mainly a blend of kerosene and used cooking oils at the moment, but with other fuels looking for an opportunity. On the Jetstar test the pilot reported that the bio-fuel was better than the standard fuel.


Those populations that have hydro-electricity with a seemingly unlimited source of water seem to be the luckiest, with only industrial and vehicle pollution to worry about. Those populations dependent on fossil fuel for electricity generation do not have a reliable and economic alternative as the renewable energy industry is far too immature and riddled with get rich quick merchants. What choices would a small Pacific island population have?
The amount of land required to produce bio-fuels at the rate we are consuming fossil fuels is more than the size of the U.S.A., and there seems to be competition between bio-fuel and food production in some poorer countries. Trials using sea algae have proved promising, but then we will see negative competition with fisheries. 
It is extremely unlikely that we will be fare-welling fossil fuels unless we have a change of paradigm in our attitude to resource consumption. The continual insistence by company boardrooms for a 10% or more annual increase in profits is both obstructive and unsustainable in the long run and encourages short term gain at any cost.

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