Tag Archives: renewable energy

Dream machine

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Painting by Katy Gibson

Painting by Katy Gibson

A machine that can do work indefinitely without any external input of energy.  It would solve the world’s energy problems, eliminate global warming and make the inventor very rich.  There have been so many attempts to design such a machine that a classification system has been established.  My machine, that does work indefinitely with no energy input, would be a perpetual motion machine of the first type because energy is not conserved – a contradiction of the first law of thermodynamics.  The second type contravene the second law of thermodynamics, usually by spontaneously converting heat into work, and the third type eliminates friction and, or other dissipative forces.

I said ‘my machine’ in the sense that I have an on-going sporadic correspondence with the inventor of a machine that is claimed to produce ‘power above the primary power that drives it’.  It is an epistemic impossibility, which means that it cannot exist within our current understanding of the real world.  In other words, if a perpetual motion machine was to be proven to exist then the laws of thermodynamics would have to be rewritten.  This would probably lead to an invitation to Stockholm to collect a Nobel prize.

Such arguments make no difference to inventors of perpetual motion machines.  Many appear to start from the premise that the laws of thermodynamics have not been proven and hence they must not be universally applicable, i.e. there is space for their invention.  Whereas the laws of thermodynamics form part of our current understanding of the world because no one has demonstrated their falsity despite many attempts over the last two hundred years.  This is consistent with the philosophical ideas introduced by Karl Popper in the middle of the last century.  He proposed that a hypothesis cannot be proven to be correct using observational evidence but its falsity can be demonstrated.

So, inventors need to build and demonstrate their perpetual motion machines in order to falsify the relevant law of science.  At this stage money as an input usually becomes an issue rather than energy!

 

The painting by Katy Gibson is from a series made as part from an art and engine collaboration between Okemos High School Art Program and the Department of Mechanical Engineering at Michigan State University.

 

 

Small is beautiful and affordable in nuclear power-stations

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Most of you will have domestic carbon footprints that are similar to mine, i.e. dominated by energy consumption, probably mainly your car and climate control in your home, and you will struggle to reduce your footprint [see my post entitled ‘New Year Resolution’ on December 31st, 2014]. We live in a fossil fuel economy and so even if you make your home entirely powered by electricity and buy a plug-in car then your utility provider is still very likely to use fossil fuel to generate the electricity supplied to you and your carbon emissions will have been simply moved elsewhere. If you are lucky enough to live in a suitable location then installing geothermal, solar or wind power for your home might be viable; but otherwise the majority of us are dependent on power-stations for our electricity.

I discussed the impossibility, with today’s technology, of providing all of our electrical power needs using renewable sources in my post entitled ‘Energy Blending‘ on May 22nd, 2013. The alternatives are either to reduce our power consumption dramatically, which seems unlikely to happen given that everyone would like to enjoy the lifestyle of typical readers of blogs, or to build a very large number of nuclear power stations.  The scale of the problem facing China was the topic of my post entitled ‘Mass-produced nuclear power plants‘ on November 12th, 2014 and it is many times large on a global scale.

A major obstacle to building nuclear power-stations is their exorbitant capital cost, e.g. £24 billion for the planned Hinckley Point C reactor in the UK. This level of investment is beyond the reach of most companies and the construction of a fleet of such power-stations to provide national needs is beyond the budget of most national governments. Small modular reactors (SMR), whose components could be mass-produced and assembled on-site, have been proposed and both their small size and the manufacturing approach would lead to considerable reductions in unit costs. Although many designs for SMRs are under development, with mature designs in China and India, progress towards implementation and mass-production is slow so that the situation is ripe for a disruptive technology from another industrial sector to transform the nuclear power landscape. One possible candidate is the fusion reactor being developed by Lockheed Martin’s Skunk works [see my post entitled ‘Mass-produced nuclear power plants‘ on November 12th, 2014] or the Travelling Wave Reactor being developed by the spin-out company TerraPower.

We need to think big about small affordable solutions instead of thinking and spending big money on massive projects that tend towards a big unaffordable solution.

Also see Bill Gates on Energy-Miracles

Tidal energy

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Photo credit: Tom

Photo credit: Tom

The world is slowing down! According to Max Tegmark, in his book ‘Our Mathematical Universe’, the rotational velocity of the Earth is being reduced as some of its kinetic energy is dissipated as tidal energy. It is possible to estimate the age of planet from the rate of slow down by assuming that at its birth it was spinning as fast as possible without the centrifugal forces pulling it apart. The answer turns out to be about 4 to 5 billion years which roughly agrees with radioactive dating of the oldest rocks in Western Australia and bits of meteorites that imply the solar system came into being about 4.5 billion years ago.

So does this imply that tidal energy is not really a renewable energy source? I think it is just an issue of timescale. Fossil fuels are seen as non-renewable because the formation of coal and oil substrates happens on geological timescales. Biomass is a bit quicker because we skip the fossilisation process and renewal is measured in months. Fossil fuels and biomass are both ways of storing solar energy in chemical bonds. Nature is much better at converting and storing solar energy than mankind. But, solar energy would appear to be the ultimate renewable energy source. Every morning its there, though often hidden by cloud where I live. The sun will eventually die but again this won’t happen anytime soon but on a long geological timescale.

Clean fossil fuel?

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The amount of energy stored in methane hydrate could be twice that of all other fossil fuel reserves based on data from the US Geological Survey, the New Scientist reported on 31st August, 2013 in an article entitled ‘Buried Treasure’.  At this point, most of you are probably wondering what methane hydrate is and where it is stored.  Microbes on the seabed eating organic matter produce methane molecules that at high pressure and low temperature combine with the water to form a hydrate, which is white crystal.  Large deposits of methane hydrate deposits are believed to lie along continental margins, mostly in ocean sediments.

Natural gas and shale gas (‘Fracking’ on August 28th, 2013) are also methane, which releases less carbon dioxide when it is burned than coal or gas and hence is regarded as cleaner.  However, methane hydrate deposits might have an additional advantage because some research has shown that the methane molecule trapped in the hydrate crystal can be replaced by a carbon dioxide one.  So we might be able to extract methane and simultaneously store carbon dioxide.  Sounds too good to be true and the second law of thermodynamics will ensure that there is a price to be paid somewhere and somehow (see post entitled ‘Sonic Screwdriver’ on April 17th, 2013 for more the 2nd law).

http://www.newscientist.com/article/mg21929320.800-frozen-fuel-the-giant-methane-bonanza.html

https://www.llnl.gov/str/Durham.html

http://www.jogmec.go.jp/english/oil/technology_015.html?recommend=1