Sunday, November 17, 2013

Solar Power, Not the Answer

7 Reasons Why Solar Power is NOT the Answer

Don’t get me wrong. I love solar power. I use solar power. If I could afford it I would be off the grid. But when people start talking about replacing our current methods of electrical generating capacity with government financed solar power I get nervous. I don’t think anyone has taken a proper snapshot of the enormity of what a project like this would entail. So that is what I did, using simple math I have laid out the details of what an undertaking of this scale would cost in dollars, the size of the needed array, storage (for when the sun isn’t shining), and possible environmental impact.  Here are the 7 reasons to consider:
The Sun delivers 1,000 watts per square meter of energy to the earth. While great from an individual’s perspective, when you put it into the context of the generating capacity of the United States the problem becomes enormous. The electrical generating capacity of the United States is 1.2 Terawatts. At face value it would require a solar panel 463 square miles in area, but things can’t be taken at face value.

Efficiency. Even the best solar panels, the very best, are 40% efficient. Most commercial grade solar panels convert less than 25% of the sun’s energy to electricity. For the sake of this article, let’s say the panels we install are 40% efficient. The 463 square mile solar array just jumped to 1157 square miles, or just about the size of Rhode Island
The Sun doesn’t shine 24 hours per day. Not only does the sun not shine 24 hours per day but we receive less energy at different times of the year. Typical Coal, Gas, and Nuclear generation has to work all day, every day. In the American Southwest (southern California and Arizona) where the sun’s energy most abundantly reaches the surface, each square meter receives an average of 6.8Kwh per square meter of sunlight every day. Again, assuming that we need to replace the current generating capacity of the United States over a 24 hour period (28.8TW/day) we would now need an array 4088 square miles in area, roughly 80% the size of Connecticut.

Cost. The current cost of 1 watt of solar power generation purchased in industrial quantities is about $0.60USD (2013). That one dollar accounts for just the panel. There is no infrastructure behind that number, no land purchases, no tracking mounts to aim the panels at the sun, no wiring, no transmission, and no labor. There are no numbers available on the cost of such a large scale installation. Again, for the sake of this article let’s assume economies of scale would bring the cost down to $.60USD per watt installed. This number is a staggering $2.541 trillion dollars or $8,094 for every man, woman, and child in the United States.
Storage. We have accounted for the generation of electricity, but remember, the sun doesn’t shine 24 hours a day. We would need to store this energy for when the sun isn’t shining. There is currently no feasible method to store this much energy. The closest method that is technologically feasible is pumped storage. During the day when the arrays are generating extra capacity the electricity is used to pump water from a lower elevation to a higher elevation, typically a reservoir. When the power is needed the potential energy of the stored water is converted using hydroelectric turbines. Using a current pumped storage facility like the Ludington Pumped Storage Facility in Ludinton, MI, some simple math shows us 1 gallon of water can provide .95 watts of electricity. Using a generalization that we have to store half of the electricity generated for later use we would need to store just over 15 trillion gallons of water. Since we need an elevated point to start with, maybe we could drain and refill a third of Lake Tahoe every day?

Transmission. If we installed our array in the Southwest we would still need part of this electricity to travel all of the way to Maine. While not impossible it would require us to generate even more electricity due to typical line losses.
Environmental Impact. Ah, the law of unintended consequences. What happens when you take 40% of the Sun’s energy and suck it out of the atmosphere over a 4000 square mile area? I don’t think anyone knows. One thing I can tell you is that the general area would be much colder, the air denser, and any moisture in it would condense. Maybe there would be a vicious fog/sun cycle over the array? What would happen to all of the desert animals, plants, etc?

Again, I am not trying to say that solar power is bad. What I am trying to say is solar power is not feasible to replace all of the generating capacity we currently utilize. Like it or not we couldn’t afford this as a country, even the United States credit card doesn’t have a limit this high. Clean energy is not the government’s responsibility, it is an individual responsibility. For what it is worth coal, natural gas, oil, and nuclear are here to stay until the individual decides it is time to change.
Source: Tin Hat Ranch, tinhatranch.com

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