Einstein’s famous equation, E=mc², does not influence everyday interactions of energy, E and mass, m. The speed of light, c is 299 792 458 m/s which is very big number and implies a huge amount of energy is required to create a small amount of mass. This means that energy and mass are independently conserved. For energy, this is the first law of thermodynamics while the law of conservation of mass is usually attributed to Antoine Lavoisier. On a planetary scale, the conservation of mass implies that we can assume that the quantity of matter is constant. Can we apply the second law of thermodynamics to matter as well as energy? One interpretaton of the second law is that Gibbs energy, or the energy available to do useful work, must decrease in all real processes. This also applies when matter moves through our economic system. For instance, we must do work to convert mineral ores into useful products which gradually degrade through use and natural processes, such as corrosion, until they become scrap and we must expend more resources to recycle them and make them useful again. The sun provides us with a steady supply of useful energy, so that in energy terms planet Earth can be considered an open system with energy flows in and out. Conversely in mass terms, planet Earth is effectively a closed system with negligible mass flow in or out, so that we do not have a steady supply of new matter from which to manufacture goods. However, most of us behave with open-world mindset and throw away matter (goods) that are no longer useful to us when we should be repairing and recycling [see my post entitled ‘Old is beautiful‘ on May 1st 2013]. Maybe we can’t reach the zero-waste status aimed at by people like Bea Johnson, but most of us could do better than the 2.2 kg of solid waste produced each day by each of us in OECD countries. That’s 2.1 tonnes per year for an average OECD household (2.63 people)!
The New Sustainable Frontier – principles of sustainable development, GSA Office of Governmentwide Policy, September 2009.
Daniel Hoornweq & Perinaz Bhada-Tata, What a Waste: A Global Review of Solid Waste Management, World Bank No.15, 2012.
Eann, please define a “REAL PROCESS”. Surely, all processes are real, in which case there is no need to label them as such. I really look forward to this clarification
Sorry, I am still in thermodynamics teaching mode. I meant ‘real’ as opposed to ”ideal’ processes that just satisfy the second law.
Here in South Australia we have had for over 20 years a 5 cent deposit on bottles and cans.
Its now 10 cents also our waste facilities are charging you for sorted trailers of rubbish or pay higher amounts for unsorted rubbish.
I know not perfect but getting there.
Pity rest of Australia does not support this drive ???
In South Australia I have amny arguments on WHY !!!!!! do we build houses on FARMLAND???
Then push farming out to the Goiuder Line where nothing can grow?
Once concrete slabs go in roads pipes runoff there goes good farm land forever!
U.S.A. is number one in waste according to the 2012 Economist link, .>2.5 kg per person per day (5.5 pounds)! I think a large component of this must be fast food waste, which is enormous. My town investigated a recycling program, but decided it was economically unfeasible, so each household is on their own. A local plant will purchase aluminum and most metals for recycling, but other than that the choices are mainly to reduce use, compost and re-tool. A popular crime throughout the U.S. is for thieves to steal outside air conditioning units for their copper content, which can be recycled for around $2.50/pound! A tragedy in recycling to me is the U.S. shipping its discarded electronics back to China and Asia where children smelt out the metals in toxic open fires.
Thank you Eann for the clarification. Now I need to know; when you say “ideal”, are you referring to “reversible” processes, i.e., to infinitesimal changes?