> 50¢/m² is 50¢/kWp in a solar concentrator, or 0.05¢/Wp, which is noticeably cheaper than photovoltaic cells, currently around 18¢/Wp, 360 times more expensive.

A photovoltaic cell is a solar panel, and a piece of aluminium does nothing, am I missing something here?

https://en.wikipedia.org/wiki/Concentrated_solar_power

I think the implication is you can use it to reflect additional light onto your photocell, improving the power output for a smaller cost than purchasing an additional cell.