The solar power sector would have to grow by 684 times before it would offset the CO2 emissions attributable to coal, more specifically, to offset 15.0 billion tons of CO2 emissions annually based on 1.0 ton of CO2 per 1.0 megawatt-hour of coal-fired electricity. Given the miniscule accomplishments of solar energy so far in the global power equation, and given that global energy output has to double as soon as possible, if the price keeps coming down solar energy as a sector has the potential to experience 50%+ annual growth for a very long time. How much would it cost today to install enough solar energy to offset 15 billion tons of CO2 emissions?Unlike Romm, who is constitutionally adverse to any real world discussion of the cost of coal replacement, Ring is willing to set down the numbers, and the numbers Ring give us are breath taking. During the last election cycle in California, voters were offered Proposition 7, an initive that would have increased the California renewables generated electricity goals to 50% of all electricity generated in California by 2025. Ring made clear both the implication of Proposition 7 and its cost:
An all-in installed price of $5.00 per watt is still low by today’s standards, but probably represents the high end of eventual costs as technology and productivity improves in the solar sector. Increasing the 10 gigawatts of installed solar power worldwide by 684 times means installing a 6.8 terawatt distributed array producing 15 million gigawatt-hours of power per year, which at $5.00 per watt would cost 34 trillion dollars. For the perhaps 1.0 billion lucky residents of the fully developed, industrialized world to pay for this via offset fees and taxes and the like over 20 years, zero interest, would amount to $1,700 per household per year. Adding the grid and storage infrastructure should easily raise that price to $2,000 each - something like $7,500 per average household per year. And this sort of accomplishment is a vital pillar of Gore’s pledge. No more coal - twenty years. Shave a few more points on future cost and call it twenty years, twenty trillion, a trillion per year. Using these same assumptions, it would cost America $6.8 trillion to replace 100% of coal fired electricity with solar power, or about $23,000 for every person in the country.
Shaving costs any further on the future price of solar is a dangerous assumption, however. Even at a cost of $34 trillion to replace coal worldwide with solar, our calculations are based on a collection of very optimistic givens; $5.00 per watt installed including storage and distribution upgrades, a 25% yield, and 20 year zero-interest financing; resulting in $2.3 billion per gigawatt-hour or 2.3 cents per kilowatt-hour for future solar. We are nowhere near this, yet to precipitously phase out coal or to participate in a doubling of global energy production, or both, this is probably what the solar sector is going to have to do.
since Californians by 2025 are going to be consuming about 1,000 gigawatt-hours per day, if proposition 7 is enacted, 500 gWh per day will have to come from wind and solar power.Ring is not an enemy of renewables, far from it. Ring also wrote:
Solar power, installed - not including transmission or storage infrastructure - costs about $7.0 million per megawatt of output; this equates to $7.0 billion per gigawatt. If this sounds expensive, it is, but to get a truly accurate price you have to also take into account yield. Even in sunny California, solar energy (in terms of full-sun-equivalent hours), can only be harvested on average for 4.5 hours per day, which means to get 500 gWh of solar generated electricity each day in California, you would need to install 111 gigawatts of solar arrays (500/4.5), which would cost $777 billion dollars.
It is inspiring to hope California can eventually reach a 50% renewables standard, or more.Now Joe Romm who has a PhD in Physics surely possess the math skills to preform the same sort of simple calculations Ring employs. If Romm disagreed with Ring's numbers, he has kept awful quiet about it. Ring is not nearly as fashionable a figure as Romm, and therefore his numbers do not get nearly as much attention as Romm's pretentious boasts. Romm knows that people, including politicians do not like to hear words like, "the numbers don't add up." Joe Romm is never going to say about solar thermal that "the numbers don't add up," even if there is overwelming evidence that this is the case. The question then is why does Joe Romm not tell the truth about the cost of solar thermal power?