Tag Archives: batteries

Horsepower driving ambition

A photograph of 'Physical Energy' in Kensington Gardens - a sculpture of a man on a horseWalking across Kensington Gardens in London last week, on my way to attend a conference on Carbon, I came across the sculpture in the picture.  It is ‘Physical Energy’ by George Frederick Watts (1817 – 1904), which really confused me because I automatically started thinking about the sort of energy that is associated with horsepower.  Horsepower is a unit of power (energy per unit time) developed by James Watt (1736 – 1819) to evaluate the output of his steam engines.  The plaque below the sculpture calls it a ‘sculptural masterpiece; a universal embodiment of the dynamic force of ambition’ and states that the artist described it as a ‘symbol of that restless physical impulse to seek the still unachieved in the domain of physical things.’  So, while the connections seemed obvious to me, it would appear that Watts was not inspired by Watt.

The conference was interesting too.  There were delegates from all over the world presenting research on a wide range of topics from new designs of batteries to using carbon as an sorbent for toxins, carbon-based composites and self-assembly of metal-organic meso-crystals.  Two students that I have supervised were presenting their research on establishing credibility for models of the graphite core in nuclear power plants and on algorithms for identifying the surface morphology in samples of graphite.

Hot air is good for balloons but cold air is better for cars

photograph of a MDI Airpod 2.0Cars that run on air might seem like a fairy tale or an April Fools story; but it is possible to use air as a medium for storing energy by compressing it or liquifying it at -196°C.  The MDI company in Luxembourg has been developing and building a compressed air engine which powers a small car, or Airpod 2.0 and a new industrial vehicle, the Air‘Volution.  When the compressed air is allowed to expand, the energy stored in it is released and can be used to power the vehicle.  The Airpod 2.0 weighs only 350 kg, has seats for two people, 400 litres of luggage space and an urban cycle range of 100 to 120 km at a top speed of 80 km/h.  So, it is an urban runabout with zero emissions and no requirement for lithium, nickel or cobalt for batteries but a limited range.  A couple of years ago I tasked an MSc student with a project to consider the practicalities of a car running on liquid air, based on the premise that it should be possible to store a higher density of energy in liquified air (about 290 kJ/litre) than in compressed air (about 100 kJ/litre).  His concept design used a rolling piston engine to power a family car capable of carrying 5 passengers and 346 litres of luggage over a 160 km.  So, his design carried a bigger payload for further than the Airpod 2.0; however, like the electric charging system described a few weeks ago [see ‘Innovative design too far ahead of the market’ on May 5th, 2021], the design never the left the drawing board.