Rations are actually not fair, but will be initiated in the early days of the energy crisis...As the crisis worsen it will lead to all out shortage..then to a sort of black market.
I expect rations to happen in the US around 2010-2011 time...and shortages starting around 2012. If the US-Israel coalition of the willing really does strike Iran..We can see shortages not long after the attack.
I think shortages is the key..Long gas lines ect...Rations are only a bandaid to the problem and wont last.