In a musical context, ELP stands for Emerson, Lake, and Palmer. Emerson, Lake and Palmer was a British progressive rock band that played in the 1970s. Their most famous songs include "Lucky Man" and "From the Beginning." Carl Palmer played the drum in the band, making him the ELP drummer. In this context, an ELP drum might refer to a drum that Carl Palmer played while in the band, or the drum instrumentation of an Emerson, Lake and Palmer song.
ELP drum can also refer to a strategy for reducing the cost a family spends on gas. In this context, ELP stands for Economize, Localize and Produce, and drum refers to the oil drum that gas is produced in. The Economize portion of the plan suggest that families voluntary reduce their spending. Localize suggests that people involve themselves in their local community and reduce their commute. Produce suggests that families focus on production rather than consumption, such as growing a garden rather than buying a bagged salad.