The True Cost Of The Global Energy Transition

[Meredith Poor + 894]

...Referencing blog post with same title.

"$15 trillion: this is the amount of money to be invested in new power capacity globally over the next three decades." Dividing by 3 is $5 trillion per decade, or $500 billion per year. In power plant terms, this would be like building 500 1-Gigawatt plants per year. Since the US alone might need 2400 of these (600 megawatts x 4.8) perhaps half of these dollars is for power storage.

"Most of this—80 percent—will be poured into renewables." Unless some sort of hydrogen (or other light element) fusion goes well beyond 'breakeven'. The minimum useful would probably be 3x, so that 100Mw input would produce 300Mw of thermal output. If the resulting thermal energy is converted to electricity at 30% efficiency, we're back to 100Mw of power. Peer reviewed papers on state of the art projects are speculating that yield could be as high as 10x.

"Under a worst-case scenario, demand for silver could top 700,000 tons." A ton of silver (atomic weight 107.8) weighs 10.49 grams per cubic CM. A 'metric ton' of water is a cubic meter, so a ton of silver occupies less than 1/10th of a cubic meter. Such a cube would be 46cm on a side. The cube root of 700,000 is 89, so 89 x 46cm would be a cube 40.5 meters on a side, or roughly 122 feet. This would be 3 40' shipping containers on one side x 15 shipping containers next to each other on another side and shipping containers stacked 15 high.

A 'standard' solar cell is 156mm x 156mm x .2 mm (200 microns). This works out to a weight of 11 grams of silicon per solar cell. If the silver represented 10% of this weight (which is a generous assumption), then each cell needs 1.1 grams of silver.

A metric ton = 1000 KG, or 1,000,000 grams. So 700,000 x 1 million solar cells is 700,000,000,000 cells. Current conversion efficiencies are about 5 watts per cell, so this is 3,500,000,000,000 watts, or 3.5 terawatts, of cell production per year. Assuming an expected lifespan of 25 years, this is 87.5 terawatts of solar panels at any one moment. Dividing this by 7.8 billion people yields 11Kw of generating capacity per person. Most residential installations are generally sized at 6Kw per person (in the United States), so while this is quite a bit higher than a purely residential user, it isn't unrealistic.

A US dime weighs 2.3 grams, although this is made up largely of nickel and copper. It's unlikely that a volume of silver roughly half that of a dime goes into each solar cell. As the ratio of silver to silicon shrinks, the wattage increases proportionally, and the total production looks progressively more outlandish.