Natural gas hit $5/mmBTU on the NYMEX for the first time in over 3 years last week, over concern about supply and a increase in demand due to to continuing frigid temperatures throughout the country. As of Jan 30, prices have backed off some but the underlying supply issues behind the spike may still play a relevant role in Nat Gas volatility going forward.
The spike involved inventory reports showing Nat Gas storage 13% below the 5 year average which raised some supply concerns. Additionally, production can be affected by extreme cold by what are referred to as "freeze offs" - pipes become constricted from frozen liquid, diminishing their output capacity. Analysts speculated that if the cold extends well into February, we may not see the anticipated price corrections as continually high demand will push prices up further. Again, prices have backed off a little bit, but with another cold snap we could be having deja vu on the issue.
Natural Gas has been touted as a cheaper, more efficient way to heat than using heating oil (the EIA estimates 50% of Americans use Nat Gas as their primary heating source, compared to roughly 6% on heating oil, the majority of which are in the North East). A major selling point when heat prices skyrocketed was that Natural Gas prices were less volatile - but as Natural Gas conversions to homes and buildings happen left and right, and Nat Gas spikes on the NYMEX is that really true anymore?
Looking at prices for Nat Gas versus Heat isn't apples to apples given the way each is measured, but if you convert the cost for Natural Gas versus Heating Oil per therm you can get an idea of the comparison.
You get about 35% more BTUs out of oil, so basically if Nat Gas ends up landing at a spot where its not at least 40% cheaper than oil, the price advantage breaks down. Additionally, thats product cost alone, not factoring utility fees and the like.
Currently Natural Gas still strongly holds the price advantage, but without serious pipeline and transport fixes, supply crunches will likely continue - particularly in the Northeast where spot prices are incredibly higher than the national average. It will be interesting to see how prices settle out (or not) over the coming months.