A turlough is a unique type of seasonal lake found in Irish karst areas which are formed through the annual welling-up of water from the underground water system. Water supplies from wells in karst topography may be unsafe, as the water may have run unimpeded from a sinkhole in a cattle pasture, through a cave and to the well, bypassing the normal filtering that occurs in a porous aquifer.
A battery rated at 180 amp-hours over 6 hours might be rated at 220 AH at the 20-hour rate, and 260 AH at the 48-hour rate. Much of this loss of efficiency is due to higher internal resistance at higher amperage rates-internal resistance is not a constant-kind of like the more you push, the more it pushes back.
Technically a battery has a certain number of joules of energy available but no one specifies them that way. What is usually specified is the ampere-hour capaciity. Ampere-hour capacity is the product of the current drawn from the battery and the time (in hours) over which that current is drawn. It is important to know the specific load the battery is experiencing when these numbers are being determined.