Thursday, March 06, 2008

Calculations

Everywhere you go and most anyone you talk to, the conversation inevitably turns to the massive, Bush-Cheney-oil/gas/coal/nuke industry conspiracy that keeps us from making the switch to pure renewable energy. Inevitably, a simple (-minded) solution is offered, like the Prius, or LED light bulbs in your home. ("If every household in the United States replaced one incandecent light bulb with an LED equivalent, we would save the equivalent output of one whole nuke plant!") So I thought I would do a little exercise in figuring out just what are we talking about in terms of scale for replacing all electricity with solar. I picked solar because it is the most proven, most reliable, most durable way we have of creating electricity that does not involve burning dead dinosaurs or playing with nukes.

Before I start, a note on methodology. I'm lazy, so I used Google to find various facts and figures. The numbers come from whatever was in the first four or five search results. I went for TLD's in the following order: .edu (typically universities) .org (anything from fronts for the oil companies to fronts for back-to-the-jungle greenies to legitimate research sites) and lastly, .com if I had no choice. I don't even bother with .gov sites for this sort of thing. The math was done with a caffeine-addled, sleep-deprived, work-stressed brain and a free Office Depot calculator. I may get the number of zero's wrong at one or more points, but I'm sure that they will not have a material effect on the outcome.

Every assumption I made was in favor of solar:

I assumed that a 200-watt solar panel actually produces 200 watts when put in natural sunlight. As the ratings are based on lab conditions using artificial light, no panel has ever produced its rated wattage sitting outside in the sun. Installers de-rate panels by 20% or more when calculating how many will be needed. But by some miracle, our panels will produce their full power.

Anywhere on earth receives an average of 12 hours of sun a day over the course of a year. I assumed that our miraculous panels will be able to harness the entire twelve hours of daylight. Currently, installers assume only 8 hours of sunlight is usable. The rest of the time, the sun is too low in the sky and is being filtered through too much air/water vapor/dust to deliver anything useful to a solar panel.

Cost figures are for the panels only. Our miracle panels do not require mounting frames, wiring, inverters, batteries, etc. to actually do something useful. Just prop them up in a field and it all Just Works. And our panels will last forever, will never need maintenance or cleaning, and will arrive at the installation site defect free.

Anytime I get tired of typing out long strings of digits, I reserve the right to round. All rounding will be in favor of solar energy.

Let's begin:

The United States consumes 3,386 billion kilowatt-hours of electricity a year. Each of our 200-watt miracle panels will produce 876 kilowatt-hours of electricity a year. That means we need approximately 3.86 billion panels.

Currently, a 200-watt panel costs $1,000. We will assume that our miracle panels cost half that. There are reasons that we will get to in a moment why our panels will actually end up costing more than $1,000 apiece, but we are trying to be optimistic. After all, despair is a sin. At the $1,000 price point, that's a cool $3.86 trillion. For comparison, the proposed 2008 federal budget is around $3 trillion. Our rose-colored scenario would cost $1.93 trillion.

A 200-watt panel is roughly 4.5 x 3 feet, which translates into 1,869 square miles, or the state of Delaware for our little project. This doesn't include the spacing required between each panel for expansion, because our miracle panels do not expand in direct sunlight.

Current production is somewhere around 500 megawatts of panels a year in the United States. I wasn't able to find exact numbers, but I was able to find several proxies (blah, blah, n-megawatts a year, half/twice/10% of total panel production in the US last year, blah, blah). The 500 megawatts number is likely a gross over-estimate. The actual number is likely much lower. In any case, at the rate of 500 megawatts per year (2.5 million 200-watt panels), it would take around 1,500 years to manufacture our panels. Obviously, we need to increase production capacity, but even at current levels, feedstocks are running tight. This is what I was talking about when I said that our panels were going to cost far more that the current $1,000 price tag because we would have to build an entire new industry to support the level of production needed to complete this project in a reasonable time frame. It's probably safe to say that some feedstocks just don't exist on this planet in the quantities that we would need, so add in the cost of moving asteroids around or some such.

So if we want to, we certainly can replace all existing sources of electricity with solar panels at a cost of a couple trillion dollars, using up an area equivalent to the state of Delaware, and taking 300 generations to complete the project.

So what's stopping us? Lets just do it!! Our children's children's children's [insert another 297 "children's" here] children are depending on us! The journey of 1,500 years starts with a single step!

Exercise for the reader: repeat the above calculations using any renewable source of electricity you care to use: wind, solar, biomass (Just how big of a cow poop pile do you need to generate 3,386 billion kilowatts? And whose back yard do you plan on putting all that poop into? I also think someone got seriously confused on units as I doubt some farmer is producing 3 megawatt hours a day from a pile of cow shit. That's the output of a fair-sized nuke plant every month.), tidal, deep ocean currents, whatever you want in whatever combination.

Go!

OK; I've had some sleep, so now I can finish what I was going to say. I probably shouldn't blog at 3am. I've also made some minor corrections and completed a couple sentences that I finished in my brain, but my fingers didn't get the memo.

Anytime you see a list of sources for electricity, coal is king by a large margin, followed by natural gas, nuclear, hydro, etc. Down at the bottom of the list, you will find 2.5-3% from renewable sources. And even that is being generous when you consider that the Department of Energy considers burning garbage to be a renewable source of electricity, which, in a way, it is. But when people think of clean renewable energy, burning trash isn't the first thing that leaps to mind. Unfortunately, that makes up the bulk of renewables; wind and solar contribute only a fraction of a percent of all electricity. Even taking on a much smaller task, say replacing all the electricity generated by petroleum (less than 2% or 61.558 gigawatt-hours) would be a monumental task.

Of course, if we concern ourselves with just eliminating CO2, we can follow the example of the French and revive the moribund nuclear industry. But if there is one thing the greenies hate more than coal, it's nuclear. And, as we have seen from the King Green himself, Al Gore, it isn't about accomplishing anything; it's about getting your mug in front of the TV camera and trying to meddle in other people's lives, all the while congratulating yourself on how superior you are to the rest of the human race.

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