Month: May 2014

Are electric cars back?

roadchaosDid you know that before Henry Ford developed the Model T Ford motorcar, the nearly 40% of automobiles on US roads were electric vehicles? I think we will be heading back in this direction if we are to have any hope of achieving reductions in carbon dioxide emissions. The implications for the national electricity grid of a major shift to plug-in cars would be very serious and has been the subject of several recent studies including a third year undergraduate dissertation that I have been supervising and from which came the opening factoid.

It is relatively easy, through not without obstacles, to envision a shift to all-electric cars; after all there are several models on the market now. However, an all-electric aircraft seems further in the future, if only because of the weight of the batteries required. Engineers would talk about the energy density, i.e. the amount of energy that can be extracted from a kilogram of kerosene compared to a kilogram battery. However, perhaps the future is not far away because the New Scientist reported earlier in the month [3rd May, 2014] that Airbus had completed the test flight of an electric plane, the E-fan. It is a two-seater plane with a pair of 65 kilogram lithium battery packs driving a pair of 30 kilowatt motors attached to the fans. The E-fan will cruise at 185 kilometres per hour and flies for an hour. Relative to a modern computer jet, this performance is similar to the early plug-in cars relative to their internal-combustion-engined rivals. But, it is an indication of bigger things to come. In the meantime, if you want an E-fan then a new division of Airbus called Voltair will be producing them by 2017.

I mentioned undergraduate dissertations because they have filled a sizeable chunk of my waking hours for a few weeks. This is an annual ritual in the UK during May when final-year undergraduate students are busy submitting and defending their dissertations. I had a pile of twelve dissertations to read and assess. Eight of them belonged to students that I have supervising in weekly one-to-one meetings since last October and the remainder were dissertations for which I was the assessor. All of the students that I supervised were studying either Mechanical or Aerospace Engineering and so the topics of their projects were associated mainly with energy and, or transportation. Some of these projects are provided by engineering companies (those with an asterisk in the list below), which guarantees their topicality and relevance, while others spin-out from my interests and research activities. So many of the topics in the list below will come as no surprise to regular readers of this blog.

Dissertation projects supervised during 2013-14:

Investigation into a redesign of graphite re-entrant seals for a nuclear power station*

Conceptual design for a carbon sequestration system for automobiles

Recommendations for achieving a low carbon airline industry

Strain-based defect analysis of industrial pipe-work*

Investigation of random frequency excitation of an aerospace body panel

Assessment of preload control of threaded fasteners in motorcycle production*

Recommendations for technology-based approaches to reduced ecological footprints

Investigation of low carbon power for plug-in electric vehicles

Advertisements

No bots here

nantucket lightThe number of comments, likes and followers of this blog remains modest, which at times can be disheartening, but then many would consider that I am writing about a boring subject under an uninspiring title.  Thumbing through the back copies of the International New York Times that had accumulated during my trip to China, I found two articles that seemed relevant.  One by John Grossman on April 25th, implied that I should use a risqué or funny name, such as the scaffolding company in Toronto called Mammoth Erections, but I suspect that this might attract the wrong sort of attention!   I was encouraged by a second article, on April 21st by Nick Bilton, to abandon the competition for ‘likes’, ‘page views’ etc., since Nick reported buying 4000 new followers for $5.  These new followers are not real people but pieces of virtual engineering, known as ‘bots’.  They are pieces of computer code designed to mimic the behaviour of people on the internet and they are getting better and better at it so that they are harder to spot.  The internet is populated by millions of them inflating the popularity of many celebrities and companies, and perhaps most worryingly political parties.  You can buy software for less than $1000 to create and control your swarms of bots.

This is one type of virtual engineering that I will not be espousing.  Instead, I am resigning myself to perpetually low statistics for this blog by attempting to keep it a Bot-free zone.

 

70,000 trees needed

 

backyard‘70,000 trees needed to print graduation papers’.  This was a headline that I spotted in the China Daily (Thursday 24th April, 2014) while I was travelling in China last moth.  The article reported that the trees would be cut down to provide the graduation papers for this year’s 7.27 million university graduates in China.  Superficially, these are very large numbers, both of trees and graduates.  However,  China has a population of 1.38 billion, which is almost 20% of the global population, so the annual graduation rate is only about 0.5% of the population compared to about 1% in England.  There are concerns in China that there are insufficient graduate-level jobs for all of the students graduating this year, which is a familiar situation in the UK.  The idea of following the Finnish approach to higher education, with more universities of applied sciences than multi-disciplinary universities, is gaining ground in China.  In the UK, EngineeringUK has estimated the number of engineering graduates needs to double by 2020 in order to sustain our engineering industry whose turnover was £1.1 trillion in 2011-12, or 24.5% of UK turnover. The shortage of engineering graduates is reflected in average starting salaries that are 20% higher than for all graduate.

Back to those 70,000 trees; they would absorb between 2 and 20 kg of carbon dioxide per tree per year if they were not felled for the graduation papers.  Carbon dioxide sequestration by trees depends on their size, age and species, see for example the sources below.  The CO2 emissions in China are currently about 7  tonnes per capita, which is about the same as the UK and about 40% of the per capita emissions in the USA, according to the EDGAR or the World Bank, so that means that 70,000 trees might balance the emissions of between 20 and 200 graduates, i.e not many of the 7.27 million!

Sources:

http://www.forestry.gov.uk/pdf/6_planting_more_trees.pdf/$FILE/6_planting_more_trees.pdf

http://www.nature.com/news/carbon-sequestration-managing-forests-in-uncertain-times-1.14687

http://sustainability.tufts.edu/carbon-sequestration/

Lost at sea

leaving usa

Loading our shipping container to leave USA

Our inability to find flight MH370 was still very prominent in the national media when I was in China last month.  The search for the aircraft and the false alarms caused by floating rubbish at sea has raised awareness about the amount of junk floating around our oceans, for instance 10,000 shipping containers are lost at sea every year,  or more than 1 every hour.  However, there are about 17 million containers in the world, so we only lose about 0.05% per annum which is a negligible amount unless its the one containing all your household goods as you move continents!

I was interested to find a high level of environmental awareness in China.  Alongside the reports on the search for flight MH370 the China Daily had a centre-page spread on Thursday 24th April, 2014 about ‘How pollution affects marine life’ with a focus on the garbage patches in the Pacific and North Atlantic oceans.  The North Atlantic Garbage Patch is more than 100 kilometres in diameter with about 200,000 pieces of debris per square kilometre trapped in the gyre. These are big numbers and if you break it down to small areas then it is one piece of debris per five square metres, which a box 2.24 x 2.24m or 7 x 7 ft.  This doesn’t sound so bad until you consider the impact on wildlife, for instance 86% of all sea turtles are affected by entanglement or ingestion of marine debris and an autopsy on a sperm whale found dead in Spanish waters concluded that the cause of death was ingestion of 24 meters of plastic.  About 300 million tonnes of plastic are produced globally per year of which it is estimated about 6 million tonnes (2%) ends up in the oceans, with 80% being washed into the sea from rivers or blown by the wind from rubbish dumps.

The second law of thermodynamics [see my post on June 5th, 2013 on Impossible Perfection] limits the efficiency of all processes with the result that engineers are used to not worrying about losses of 10% or less so that the losses to the ocean of 0.05% and 2% mentioned above would be considered negligible but the enormous scale of human processes mean that the losses are having a significant impact on the fauna of the planet.  Engineers need to lead society towards a more harmonious and protective relationship with the rest of the planet.

Source: http://www.billiebox.co.uk/facts-about-shipping-containers/