11.   In the next two years, Shell Technology Ventures hopes to sell technology that produces heat from natural gas without a flame.

12.   Instead of maintaining a preset temperature by switching on and off throughout the day, however, a tankless hot water heater produces heat only when water is flowing.

13.   Jones and Stano probably lost consciousness within milliseconds when the initial surge hit, presuming the corresponding amperage -- which produces the heat -- was sufficient, Sperry said.

14.   Minutes later, a low-power laser beam that produces no heat is aimed at the retina.

15.   Muscle produces more heat than fat, she says.

16.   Natural gas generally produces heat more inexpensively than electricity, but gas prices are rising, so the gap is narrowing.

17.   One theory is that a contaminant in one of the drums reacted with the nuclear waste, producing heat.

18.   Recessed light fixtures in the ceilings of rooms produce enough heat to be dangerous if insulating materials get too close.

19.   Seventy such flowers produce the heat of a human being at rest reading a newspaper.

20.   Starch inside metabolizes quickly, producing heat, which melts the chemicals.