Page added on April 14, 2013
While we are currently experiencing a glut of natural gas that has brought the price down from around $13 to around $3 per million BTUs, there are questions as to how long our natural gas supplies will last.
The debate that has caught people’s attention is over whether we should export natural gas, as LNG to Asia and Europe.
The president of DOW Chemical has said we shouldn’t, while many others have said we should. Both views have facts on their side.
On one side, there are projections that we have 100-year supply of natural gas based on current consumption. The other side says that the estimates of natural gas reserves are overstated and that exporting natural gas will drive its cost up and prevent industry from creating new chemical industry jobs in the United States.
Here are some facts that need to be taken into consideration as each of us contemplates the best course of action for the United States.
The highly respected Potential Gas Committee1 (PGC) estimates that there are 2,384 trillion cubic feet (Tcf) of technically recoverable reserves of natural gas. Much of this is from shale where fracking has released natural gas previously locked in shale.
Based on current usage of 22.34 Tcf, there is a 98 year supply of natural gas2.
A few other experts estimate larger reserves than does the PGC3.
There are other experts, however, who say that the amount of shale-gas is overstated, perhaps by twice that which will actually be produced.
In addition to the supply issue, there are questions about how much additional demand will be created by new uses.
For example, new demand could come from:
Each of these usages impact supply differently.
Converting coal-fired power plants to natural gas
It’s very likely that 25% of existing coal-fired power plants will be converted to natural gas. It’s less likely, though possible, especially if there is a carbon tax, that 50% will be converted to natural gas.
Exporting LNG.
FERC is reviewing licenses for 19 export terminals, which, if approved, would have an export capacity of approximately 10.4 Tcf per year.
FERC List of Possible LNG Export Terminals

Long haul trucking
Long haul trucks use approximately 54 billion gallons of diesel fuel6 annually. Replacing this with natural gas would use 7.3 Tcf of natural gas.
It’s possible that natural gas will replace a significant amount of diesel fuel, but not all of it. Even so, if natural gas replaced all diesel fuel and this was added to current consumption, it would result in a 74-year supply.
Usage summary:
Combining each of these usages, summarized here, together with current usage, and then using the PGC’s estimate of 2,384 Tcf of supply to determine the number of years of supply, results in a 48-year supply of natural gas.
Since it’s not likely that 50% of coal-fired power plants will be converted, or that all proposed export terminals will be built, or that all diesel fuel will be replaced by natural gas, the number of years supply is probably greater than 48 years, possibly 60 or more years when these three new uses are added to current usage.
For example, huge supplies of LNG are being developed in Australia and the Mideast. These could reduce the opportunity to export LNG from the United States. Export terminals with two trains cost around $8 billion, so that investments won’t be made without solid contracts from importing countries. Only one of the 19 proposed LNG export terminals has been approved thus far. In addition, shale gas in China and India could reduce demand for LNG.
Significant automobile usage of natural gas or significant use of fuel cells in homes would also reduce years of supply, but both are unlikely.
This discussion doesn’t include the very large quantities of natural gas found, or expected to be found, in Canada’s shale.
If North America is viewed as an integrated market, the number of years supply would be greater than the 60 mentioned here.
The critical issue is whether the supply of natural gas, as estimated by the PGC, is reasonably accurate.
There is legitimate concern whether the wells producing shale gas will produce as much as is currently estimated. Decline rates, for example, are far more rapid than from traditional wells.
Two additional critical issues could affect supply and demand.
Significantly curtailing fracking would eliminate any of the possible new uses outlined here.
A carbon tax could increase demand by forcing the closure of more coal-fired power plants, while, at the same time, reducing supply by making drilling, processing and transporting natural gas more expensive.
There‘s no simple answer as to whether natural gas should be exported or whether greater usage for other purposes will significantly increase the price of natural gas, from around $3, to, say, $5 per million BTU, which might deter investment in chemical plants.
It should be noted that the above calculations represent estimates, and are not absolutes.
For example, in calculating the amount of natural gas needed to replace coal, the relative thermal efficiencies of coal-fired power plants and natural gas combined cycle power plants, 33% and 55% respectively, were used.
Not included in this discussion is whether new supplies can be found, such as methane hydrates that would vastly increase the supply of natural gas.
These estimates do however; provide a framework for understanding the issue and for making decisions.
Notes:
6 Comments on "Do We Have Enough Natural Gas?"
BillT on Sun, 14th Apr 2013 12:14 pm
Well, the best holes already have straws in them sucking out so much that it is collapsing the price and many companies along with it. Next step is a massive jump in price as the excess is gone and there is a slow resumption in drilling new holes. The quick jump in price will likely stop and conversion and make another go at it much harder.
All ideas to export the stuff is plain stupid but greed will probably make a stab at it. I wonder what is going to happen to the investments when these terminals are finally built and the world economy crashes taking the possible markets with it?
mo on Sun, 14th Apr 2013 2:52 pm
Whats not stated is that 100 year estimate includes small pockets of gas(not economicly worth drilling) . Methal hydrates and new discoveries (speculative)?. Shale wells deplete so rapidly there’s no way they can come up with a total reserve number for these plays. Ive seen other estimates of 22 years. And some as low as 11 years. All this infromation and misinfromation gets confusing at times!!!!!
DC on Sun, 14th Apr 2013 3:37 pm
Q/Long haul trucking
Long haul trucks use approximately 54 billion gallons of diesel fuel6 annually. Replacing this with natural gas would use 7.3 Tcf of natural gas.
RoFL! How about getting rid of long-haul trucking all-together, the least efficient form of transport ever devised, outside jet cargo that is, with TRAINS. And electrified ones at that. Think of all the diesel and N.G. we’d be saving, not to mention the staggering pollution and other forms of damage those ‘rigs’ do. Think powering them with NG will do much about any of that? LoL!
Oh, but we dont want to do that do we, too ‘expensive’. However the search for a slightly different toxic fuel to shove in the tanks of all those ‘rigs’ is cheap and will occur seamlessly, on time, and under budget, right?
Idiots…
Bob Wallace on Mon, 15th Apr 2013 4:35 am
Just some tidbits to toss in the stew…
In 2010 the US generated 988 TWh (Terawatt hours) of electricity using natural gas. In 2012 that number increased to around 1,470 TWh. A 49% increase in burn rate. Almost certainly 2013 will show another rise.
I wonder how much Canadian tar sand NG use has climbed since 2010?
In January 2012 the US Department of Energy lowered the 842 tcf ‘known and proven’ to 482 tcf based on more detailed information provided by gas explorations in shale deposits in the preceding year. Wells are slowing production much faster than was expected. That’s a 43% drop.
At the end of 2012 the Potential Gas Committee (PGC) increased their estimate to 2,384 tcf, 25% (486 tcf) more than the previous record-high assessment 2 years earlier.
Previously in 2010 the EIA and PGC estimates had been very similar. There’s some work that needs to be done here. We’ve got rising burn rates and confusing reserve numbers.
econ101 on Mon, 15th Apr 2013 6:55 pm
The best holes have yet to be drilled. The gas potential is phenominal. There is a very interesting article about that right now on Seeking Alpha and I quote:
Last month, WPX commented that the well indicated 20-30 Tcf resource potential on its acreage in the play, a staggering amount. According to WPX, the Niobrara and Mancos tests showed “hydrocarbon saturation across tremendous thickness in a highly over-pressurized environment… The potential of this new resource is huge…”
this is in the Piceance Basin in Colorado. There are several other huge discoveries opening up in the west too. These developments are significant and will add tremendously to our long term supply. They will also be very valuable to the western states because they are located in a central area. Its tough to ship gas all over the country from back east in PA.
econ101 on Mon, 15th Apr 2013 7:01 pm
Trains are already electrified. They just dont use electricity from a third rail. An almost impossibly expensive and inefficient endeavor. Besides if we didnt have trucks what would you do with the stuff once it got to the train station?
Trains haul in bulk very efficiently. The more handling the less efficient. Its cheaper and less handling to ship say frozen turkeys and deli product by truck. They arrive directly at their intended location without an addition load/unload to truck. Also the delay in the process caused by the extra stop takes time and product can get old.