The red stack number when adding all the sub-components together is approximately 111 kWh per day per person. Multiplying this by the population of Hong Kong, 7 million, gives 777 million kWh per day total.
Next, I assume that the average power of the sunlight per meter squared in Hong Kong is 110 W/m2 and that each one of the PV panels are 10 percent since the cheapest kind would be implemented in mass productions. By using the formula (110 W/m2)(.10)(x m2)(1 kW/1000 W)(24 hours/1 day) = 777,000,000 and solving for x, it is computed that 2.94 billion m2 area covered by PV panels are necessary to produce the red stack energy amount.
