Peak gas
According to M. King Hubbert's Hubbert peak theory, peak gas is the point in time at which the maximum global natural gas (fossil gas) production rate will be reached, after which the rate of production will enter its terminal decline. Natural gas is a fossil fuel formed from plant matter over the course of millions of years. It is a finite resource and thus considered to be a non-renewable energy source.
The concept of peak gas follows from Hubbert peak theory, which is most commonly associated with peak oil. Hubbert saw gas, coal and oil as natural resources, each of which would peak in production and eventually run out for a region, a country, or the world. Since Hubbert's initial predictions in 1956, "the proper application of ever more powerful statistical techniques has reduced much of the uncertainty about the supply of oil and natural gas". One view in 1997 was that Hubbert's use of an exponential decline model was statistically adequate in explaining real world data. However, longer-term experience has shown the predictions to be incorrect.
The world gets almost one quarter of its energy from natural gas. The consumption of natural gas has nearly doubled in the last 30 years. The most important energy agencies in the world are forecasting increases in natural gas demand in the next 20 years. The largest increments in future gas demand are expected to come from developing countries.
Of the three peaks, Hubbert found the peak in discoveries most difficult to define, because of large year-to-year scatter, and the phenomenon of ñreserve growth.ò Initial estimates of a discovery are usually much lower than ultimate recovery, especially if the conservative estimate of proven reserves is the measure. As the discovery is drilled out, estimates rise. Sometimes estimates of recoverable oil and gas in a discovery continue to rise for many years after the discovery. To find the peak in discoveries, Hubbert backdated reserve growth to the date of field discovery.
Despite the reported fall in new-field discoveries, world proved reserves of natural gas have continued to grow, from 19 billion cubic meters (bcm) in 1960, 45 bcm in 1970 and 84 bcm in 1980, to a record high 200 bcm in 2012. A researcher for the US Energy Information Administration pointed out that after the first wave of discoveries in an area, most oil and natural gas reserve growth comes not from discoveries of new fields, but from extensions and additional gas found within existing fields.
