Build once, use forever (BOUF). That’s a desirable property solar power has.
Here are some real world examples to illustrate this:
The Suez Canal was opened in 1869 and is still in use today, 144 years later. The final cost of building that was more than double the original estimate, and the Suez Canal Company was in financial difficulties for the first couple of years after the opening, since traffic was less than expected.
Does anyone today care what the cost of building that project was in the 19th Century? Isn’t it evident that this piece of global infrastructure that has dramatically increased World trade has paid its cost back to humanity many times over?
Another example would be the Itaipu dam, the World’s largest hydro power plant by electricity generated per year (94.68 TWh in 2008, supplying 90 percent of electricity consumed in Paraguay and 19 percent of electricity consumed in Brasil).
It was built in a joint effort between these two countries between 1966 and 1984. Construction cost was 19.6 billion dollars.
And like the Suez Canal, it will very likely be used for centuries to come. That’s important when discussing costs. For such a project, the real cost per kWh for society is extremely low. The calculated cost for the company building this infrastructure of course needs to reflect the fact that they must break even in a reasonable amount of time. They can’t wait centuries to pay back their capital.
But that doesn’t change the fact that energy from such a BOUF project is basically free after the capital investment has been paid back after a couple of decades. The turbines may need to be replaced every once in a while, since they have moving parts. But the dam follows the BOUF principle. Build once, use forever.
The same is probably true for solar power. Solar panels have no moving parts. Therefore I expect them to be useful for centuries, just like dams and canals. That in turn obviously means that if you place a large number of solar panels in the deserts in Africa and Mongolia, the cost of doing so as calculated per kWh generated over a couple of centuries would be basically zero.
The same is true for the mirrors used for concentrated solar power. A mirror will reflect sunlight for centuries, just like a dam will collect water for centuries. Like with the dam, you need to replace the turbines every once in a while, but you get a source of energy to power them for free, if you take this long-term view.
The same is true for the towers built to mount wind turbines on. While the turbines will only work for decades, the towers may be used for centuries.
In contrast, fossil fuel is ruled by the principle “Burn Once, Lose Forever” (BOLF).
Fossil fuel is basically only very old biomass. Humanity is burning through stocks of biomass stored in 5.3 millions of years every year. The only reason fossil fuel looks so cheap as it does now is that no one considers the cost of replacing it once its gone. Once that little cost factor enters the equation, people would be crazy to burn this treasure just to get a bit of heat.
And that’s before global warming costs even get mentioned.