With, a propane supply glut that could keep prices down for several years, farriers can likely trim the expenses for fueling their gas forges for shoemaking and modification work. In fact, the price of this gaseous byproduct has already plunged 18% so far this year.

The Wall Street Journal has reported that propane production has surged to an all-time high amid a boom in U.S. energy production. For the last year or so, relatively high propane prices have helped energy companies offset the impact of a decline in natural gas and crude oil prices. But that time is over, as propane prices tumbled to a 13-year low earlier this month.

Propane supplies are rising so fast that energy traders maintain there’s a chance that available storage could run out before winter, the time of year when propane inventories usually decline due to increased residential heating needs. Mid-June supplies were at their highest level in more than 45 years.

The U.S. Energy Department says retail propane prices averaged $2.93 per gallon in April, and are expected to remain weak throughout the summer.