If you are dead certain convinced that natural gas prices are rising faster than most people anticipate, then purchase some futures contracts to a) hedge the price increase and b) profit handsomely. Here is a historical chart of the closing price of NYMEX Natural Gas contracts. Here is the Energy Information Administration's weekly report. Some history on the NYMEX contracts; from this page, you can also click around for all contracts, current open interest on each contract, and closing prices. A rise is indicated, but not "triple". If you are correct, and put your money where your convictions lay, you would walk away an extremely wealthy individual.
I've learned to respect the futures markets. They tend to be fairly accurate price discrimination tools. Not perfect, of course. But what you are linking to is not positing some outlier event, which is what these markets are relatively poor at accomodating, but structural issues, which is exactly the type of issues these markets tend to price in fairly accurately. Please share any information you have that indicates a 3X price increase is dialed in, I just don't see the evidence.
Take your chart back 3 years. Now show me another energy source that had even 70% of the average increase. BTW I have made some very good money from Natural Gas Futures. I've lost a little now and then, but I've kept far more than I've lost. This problem keeps getting worse. Go look at the spot market for winters between 94 and 96. These prices drove some new pipeline building (the industry in which I work). The US seems to only respond to crisis.
Since 1987, there has been a strong push (and a good one I think) to move new electric generation to using Natural Gas for lower emissions and lesser dependence on foreign oil. At the same time, environmentalist have been shutting us out of our own natural gas resources. An forced increased demand and a forced decreased supply result in the current pricing.