The heat -- no matter what the source -- is normally used to heat water to the boiling point and produce steam.
(The heat -- no matter; is normally used; to heat water to the boiling point and produce steam) (The heat -- no matter; to heat; water; to the boiling point)
The heat -- no matter The heat -- no matter
is normally used to heat
to heat water to the boiling point and produce steam
water to the boiling point