Consumers are sometimes surprised when they open their natural gas bills. The rate that their local utility charged this month could be 25 percent higher than it was just last month. That same rate, however, could at the same time be 30 percent lower than it was last year. This leads some consumers to wonder what is going on at the utility. The fact is that natural gas price changes are driven by several different factors, some of which the utility has control over, and others it does not. Some of these costs are subject to regulatory oversight while others are not. Some of these factors change infrequently and in small increments, while others swing widely from month to month. Still others vary by the season.
Changes in natural gas prices are caused by five principal factors. Natural gas rates change when there are:
The price of gas at the site of production is referred to as the commodity price or wellhead price. Of all the cost components, natural gas commodity prices are by far the most unstable and the least predictable. Figure 1 shows monthly wellhead prices of natural gas from 1999 to 2009. It is clear that these prices move around quite a bit from month to month and from year to year. Natural gas price volatility is among the highest of all commodities that are traded on major market exchanges. The price can unexpectedly double in a matter of months. It can also tumble by 50 percent just as fast.
The natural gas commodity price is so volatile because it is a market price, not a regulated price. Market forces reflect the underlying supply and demand situations. Since there is no regulatory oversight a sudden unexpected cold snap can send prices soaring. Conversely, an unexpected decline in the price of competing fuels, such as oil, can cause industrial customers to use much less gas than expected and the price of natural gas can decline precipitously. Figure 1 shows monthly prices. The daily prices are even more volatile.
Interstate pipeline costs represent the space (capacity) on the pipes, that transport natural gas. Pipeline costs are much more stable than are commodity prices. The overall level of pipeline charges changes very little from year to year. Occasionally, the FERC sets new pipeline rates that must be flowed through to consumers, but in most years the pipeline rates are fairly constant.
Generally no. The PSC requires most of the state’s gas utilities to recover more of its charges for pipeline service in the winter than in the summer. Why does the Commission do this? Increased demand in the winter, not the summer, determines whether the utility must contract for new pipeline capacity. There is plenty of space available on the pipeline in the summer so that even if everyone installs natural gas fired grills for summer barbecues, the utility simply runs more gas through its space on the pipe. So customers who increase usage in the summer cause the utility to incur commodity costs, but not pipeline capacity costs.
The same cannot be said of customers who increase their winter usage. If numerous customers convert from, say, fuel oil to natural gas for home heating, the utility must make sure that it has enough space on the pipeline to meet the increased demand. If it does not, it will have to arrange for more space on the pipe. Who should pay for the increased pipe capacity, the customers who installed gas grills for summer usage or the customers who installed gas furnaces? Those that installed the furnaces clearly caused the need for the new capacity, so from a cost-causer / cost-payer perspective, those customers should pay for that capacity. To link cost-causer with cost-payer, the PSC requires utilities to use a seasonal pricing approach to collect pipeline costs. The concept is shown in Figure 2 below. The winter period runs from November through either March or April, depending on the utility. The important point to note is that pipeline charges increase by about $0.10 per therm on November 1. This is a hefty increase for most consumers. This means that even if commodity costs are stable from October to November, gas bills are likely to rise noticeably once October ends.
Natural gas rates can change due to reasons that occur irregularly. For example, in recent years several Wisconsin utilities were required to pass back to customers a refund of pipeline costs. Other utilities might be allowed to or required to pass on to consumers slight surcharges or credits based on their performance under gas cost incentive mechanisms. It is difficult to know when and if these types of costs might be incurred. In any event, they tend to be quite small relative to the commodity, interstate pipeline, and distribution service costs.
These rates reflect the utility's cost of maintaining and operating its local system for distributing natural gas to homes and business. It is surprising to many consumers that the portion of the business fully regulated by the PSC, namely the basic distribution business, is usually not the culprit when it comes to significant natural gas price changes. These costs are, like interstate pipeline rates, fairly stable from year to year. Unlike interstate pipeline rates, however, local distribution rates do not vary by season. These rates change only when the PSC has a formal rate proceeding for the utility. In most cases, these rates are not changed more frequently than once every two years.
**There are many factors that cause natural gas price changes