A fundamental question .... and runs right into the idea that we are VERY unlikely to have everyone be self sufficient so long as there are some economies of scale. (The idea of a "backyard furnace" for example is trumped by the efficiency of the large scale steel mill.) Sure, we could be using less (zero? ... I don't think so) energy, but there are benefits from large scale activity which are exploited. In addition, we gain further benefits from agglomeration effects. The positive spillover from one activity to another.... would you want to give that up?
I know a lot of people want to look the other way, but if really focusing on sustainability and reducing GHG emissions, we need to take a look at a less popular area to consider: what we eat. It is incredibly inefficient to grow food or use energy in catching food to feed to animals and call them food. Transportation is huge, but agriculture, especially animal agriculture, is the cow in the room. Livestock does have a long shadow even if we don't want to talk about it.
Reducing transportation to zero isn't sustainable for human sanity, it's prison.
Thanks for your replies . It is very difficult for the business community to give up current approach to management. The idea of sustainability will require much of the management philosophy to be re written, however this will be gradual and will not be achieved over night. Accounting for green capability by counting GHG emissions if done accurately might show us how wrong we are in making the choices for certain products and services. Our supply chains are currently too complex in some areas and staff therein not well trained to achieve the task of accurate GHG emissions.
Researching the sustainability reports of the large supermarkets in UK I see that every supermarket tries to use a different benchmark year to start the process of reduction of resources in packaging and other wastes. However there is some activity where all supermarkets have come together to achieve a common goal . The Courtauld commitment I quote the focus of part of the accord "Phase 2 (2010-2012) built on Phase 1, still aiming to reduce primary packaging and household food and drink waste, but also included secondary and tertiary packaging, and supply chain waste. It moved from reducing weight to reducing the carbon impact of packaging."
It is possible through these initiatives that there is a change in thinking which will achieve the objective of sustainability