We can now calculate a lot. There are countless climate models, including theoretical assumptions, if we built 20% -50% of the Sahara with photovoltaics, the temperature in the Sahara would increase significantly due to the much darker surface of the photovoltaic modules. Less radiation will be reflected back into space by the bright desert sand, in short the albedo would decrease and the earth energy imbalance would increase. It’s up to 2 degrees Celsius more. Conversely, we could cool the earth regionally and globally with more surfaces radiating into space.
Photovoltaics shouldn’t face a headwind now, on the contrary: I think we should rethink power plants. We lost millions of square kilometers of albedo to the melting of ice. Our earth is getting darker and therefore attracts more heat from the sun and thus heats up additionally.
Harvard’s calculations of Meer: Reflection, according to, mirrors placed horizontally on the surface are able to reflect up to 90% of the heat radiation back into space. That is up to 300 watts per square meter. Compared to ice, which we lose as albedo, about 3 times as much. It can also be expected that mirrors are around 10-20 times more effective in cooling the planet than freshly planted forests.
Also this Takling Climate Change through Radiative CoolingPIIS254243511930354X is suggesting, that only a relative small space is needed to mitigate earth energy imbalance through CO2 rise.
This is where the model calculation of vertically mounted double-sided modules (VMBM) comes into play. The result was that large parts of the earth due to their high albedo, they realize that this term seems to play an important role, to be suitable for this assembly. The yield is even the same as with other types of installation, but significantly higher in the morning and in the evening.
Therefore, it is obvious in the future to equip dark surfaces such as bodies of water and seas with floating mirrors and to be able to finance them better, to install photovoltaic modules standing between them.
Also maybe we should use plastic free materials like hemp and concrete(aka ferrocement) to build structures that are elevated from the water surface with floating pillars, like the off-shore wind or oil Plattform do to reduce the movement between the Pontons.
There are already some subsidies for this dual use of photovoltaics. So if you have a little money available, please contact me and I will calculate such a pilot system for you.
CO2 Off-Set with Solar Radiation Management(SRM)
How many Watt per Square-meter should be compensated:
Albedo(1 für 100%)
the space of Austria: