Using 82 Terawatts of solar and wind to Green the Sahara as a side effect would cost at least $82 trillion
Researchers simulated the effects of around 79 terawatts of solar panels and 3 terawatts of wind turbines. Computer modeling looked at the effect of covering 20 percent of the largest desert on the planet in solar panels and installing three million wind turbines.
There would be 16X the rain in the aridest parts of the Sahara, and double that of the Sahel.
It should be noted that massive amounts of solar and wind power does directly alter the climate.
The researchers are claiming that this energy side effect would be a net positive for the world. The extra rain going to the Sahara would not be more dryness elsewhere.
Global investment in renewable energy (Solar, Wind, Hydro and biofuel) edged up 2% in 2017 to$279.8 billion, taking cumulative investment since 2010 to $2.2 trillion.
Solar alone accounted for 98GW, or 38% of the net new power capacity coming on stream during 2017. China 53GW installed with solar investment of $86.5 billion, up 58%. Renewable energy investment in the U.S. was down 6% at $40.5 billion. Europe had a decline of 36% to $40.9 billion. $154 billion was spent on solar and $100 billion was spent on wind power in 2017.
52.6 GW of wind power were installed. Wind Power Capacity reached 539 GW in 2017.
Let us assume that it only costs $100 billion to install 100GW of solar power. Instead of the $157 billion.
Let us assume it only costs $50 billion to install 50 GW of wind instead of $100 billion.
79 terawatts of solar panels would cost at least $79 trillion.
3 terawatt of wind power would cost $3 at least trillion.
This would not include costs for the land and power grid improvements and backup power or power storage.
It would cost about $2 trillion a year to replace the 2 terawatts of solar and wind that would wear out every year.
the build rate would need to be about 4 terawatts per year in order to complete in 20 years before the major annual replacement would begin. This would be about 40 times more global solar than in 2017 and about three times as much wind power.
The installed renewable gigawatts are for peak power. There is only 20% capacity factor for solar. Solar and wind have to be replaced every 15 to 30 years.
$15 trillion for 1.591 terawatts of constant power from solar and wind
There was an analysis that 1.591 Terawatts of constant solar and wind power built over four decades would cost about $15.2 trillion. Constant power requires a 5X buildout of solar and 3X buildout of wind compared to the prior analysis.
Over the conservative 60-year life of a nuclear reactor, the wind and solar for US Roadmap would need 36 billion square meters of high-performance 160-watt panels. Here is the calculation for that number:
• Utility PV: 14.5 billion
• Residential: 2 billion
• Commercial: 1.5 billion
• Sub-total: 18 billion
• With one panel replacement: 18 + 18 = 36 Billion m2 of panels
Even with factoring in NREL’s future cost discounts – which partially depend upon improved panel conversion efficiency – the 60-year cost for PV would still be $7.6 Trillion.
The Roadmap’s utility PV solar breaks down as follows:
• 14.5 billion m2 of panels
• Initial installation: $4.1 Trillion
• With one panel replacement and three inverter replacements: $7.4 Trillion
• Minus 28% (NREL’s utility PV future discount), 60-year cost = $5.3 Trillion
According to the 100% Roadmap, utility PV farms in 2050 would deliver 488.9 GWs average, or 30.7% of the 1,591-GW grid, for 34.9% of total cost.
Utility PV quick numbers:
• 490 GWs
• 31% of grid
• 35% of cost
By Brian Wang