If there was a war on perhaps the government would bring back posters like this one from World War II asking the public not use public transport unless it was absolutely essential. Petrol was rationed, so the price was irrelevant.
Changing the subject for a minute think about these two scenarios :
(no frogs were harmed during this thought experiment)
So as fuel, food and water (making and supplying fresh water is very energy intensive) gradually rise, we just grumble a bit and hope the government will sort it out for us. Contrast this with “Any society is only three meals away from revolution” (Rimmer from Red Dwarf?) and you see why I mentioned frogs.
This is the problem with all the hype about the environment , it’s difficult to see how your behavior affect the problem, and although I agree with Steve and James about the need for sustainable societies, I am not sure that anything will change much unless there is a shorter term benefit in all of this at a personal, business and political level.
So you realise it might be much better to work from home one or two days a week. The environment benefits, someone else can use your seat on the train or your parking space, but is your user community happy about that, and does your manager trust you to do the right thing when your not under their nose?
Better yet if you can leverage some technology to enable your users to work flexibly like we do at Microsoft. Is that investment OK with the board, trustees etc and what’s in it for them? You probably wouldn’t get far saying it would save a few tons of carbon, but you could reasonably argue that the benefit is a better motivated workforce, and a more attractive place to work (which helps with recruitment and retention) and reduce the need for as much office space into the bargain.
So my advice is to try a side on approach and like any good IT idea you have imagine you are asking the questions in Dragon’s Den!