chuck wrote:
So is energy without power really impossible, Cecil?

Roy has already answered the basic question from an engineering
viewpoint. Physicists often consider "power" to have a different
definition than the engineering definition.

From the IEEE Dictionary: "power - The rate of generating,
transferring, or using energy." (agrees with Roy)

From "University Physics" by Young and Freedman: "power is the
time rate at which work is done." i.e. only the "using energy"
portion of the engineering definition.

A certain physicist I know will argue that no work is being done
in a lossless transmission line so there is no power there. He will
say the existence of 100 watts at 1000 points along the line means
there must be 100,000 watts in the line. He will say that a Bird
wattmeter doesn't measure watts. He will say that a power
generating plant doesn't generate power and a transmission line
doesn't transfer power. He will also say that reflected power
doesn't exist because it is not doing any work. He will say that
for an EM wave in free space, ExH has the dimensions of watts
but it isn't power because no work is being done.

As Roy indicated, engineers have a wider definition of "power".
Energy without power is certainly possible, e.g. a DC battery
with zero current. However, for a constant steady-state power
level associated with an EM wave, energy and power are inseparable.

I like to use a one-second long lossless transmission line in
some of my examples because it is impossible to hide the joules.
A one-second long line with 200 watts forward power and 100 watts
reflected power contains 300 joules that have been generated but
have not reached the load. Since EM wave energy cannot stand still
(or slosh around side to side) it is only logical to assume that
200 of those joules are in the forward wave and 100 of those joules
are in the reflected wave both traveling at the speed of light.
--
73, Cecil http://www.qsl.net/w5dxp