Dave wrote:
so roy has correctly calculated the standing wave 'power' to be zero at two
points on the line. i am sure that yuri will take great exception to this
result showing there is no power in the standing wave.

Power is the measure of the energy flow past a measurement
point. There is no net energy flow in pure standing waves.
Since the standing wave current phasor is always 90 degrees
different from the standing wave voltage phasor,

Power = V*I*cos(90) = 0 watts Note that V and I do not
have to be zero. There is simply no real power in a pure
standing wave. However, there are plenty of joules in
standing waves that can be converted to real power at
the expense of the standing waves after key-up.

All of the standing wave energy is contained in

Reactive Power = V*I*sin(90) in units of VARS

From the IEEE Dictionary:

"reactive power - For sinusoidal quantities in a two-wire
circuit, reactive power is the product of the voltage,
the current, and the sine of the phase angle between them."
--
73, Cecil http://www.w5dxp.com