The trans in D whilst stationary and foot on brake renders a 1% load on the engine, only the torque converter is slipping at this point which is perfectly normal as its built for this.
Infact while you drive your torque converter is always slipping slightly until you hit the range where the torque converter clutch locks up.
If you are concerned abt saving 2 drops of fuel - best stop driving the car and take a bus.
