Allow about 10 mins

Dissipation occurs when, over time, mechanical systems interact with each other and frictional forces tend to increase the thermal store of the interacting objects. This thermal store is less usable,

It is sometimes tricky to express ideas about dissipation without contravening the idea that energy is conserved. It is important not to follow up discussions about energy being conserved with representations that suggest it is used up. Instead, refer to energy resources or useful sources of energy being used up.

Employ phrases like: 

“the fuel is used up”,
“the energy resource is used up”.

 Avoid phrases like:    

“energy is running out”,
"energy is consumed”,
"energy is used”,
"energy is used up”,
"energy is lost”.