Oils volatile price.

Oil is a diminishing resource with a volatile price and we need to be using much more of our abundant renewable energy for our transport system. The current price of $30 per barrel will not be good news in the long term as the world does not like volatility with the important resource. 
​http://ourfiniteworld.com/2016/01/19/why-oil-under-30-per-barrel-is-a-major-problem/

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