My calculations.50m x 50m building footprint. 10 stories high at...

My calculations.

50m x 50m building footprint. 10 stories high at 3.6 per floor = 36m. This gives the 25000m2 of letable floor space.
North, East and West walls with CPV = 5400m2 of windows.
Extra cost for the windows $60 per m2 = $324,000
Extra cost for electrics to windows = (a guess) $150,000
That's a total of $474,000 to add the tech to the building. Probably would be higher than this figure.

I used the cost of power in Perth .283272c per kWh (average may be better to use?) but lets use the 34c as per Chippy. The Government are telling us power prices are going to come down, and large buildings don't pay what we pay, they get a discounted rate. so I think 5% a year upwards is a bit much.
Take into account the degradation of the tech over time. CPV say 20 year lifespan possibly 25. Lets say the lose 1% a year of power production.
Extra cost to keep windows clean at all times. They work on light so need to be clean to get optimised power.
Outside temp doesn't matter does it? as they work of light not heat. 12 degrees, 20 degrees what does that matter.
Savings as per Chippy over 20 years (life span of product = $432,840

To me this is a break even at best. Why would you go to all the trouble.