Some thoughts on energy

Wednesday, December 19, 2007 

I recently rediscovered an email discussion I was having about global warming and solar power. I kind of enjoyed it…

Global warming not really open to reasonable debate. There’s a collection of industry flacks who spit out pseudo-science refutations of the real science of climatology, harping on any admission of statistical or projection error as a fatal flaw in the whole concept. It’s disingenuous, but effective given the ultra-right’s iron grip on the media.

The basic fact is we’re pushing the environment very quickly into a new regime which will cause significant changes and bring unexpected hardship to much of humanity, at the extreme threatening the viability of the planet for supporting humans in comfort. It might well be the sort of change that brings about that 2/3rds reduction you seek [in population], but it is unlikely to be a means that most people find optimal.

Is it avoidable? Yes, literally effortlessly and without any meaningful sacrifice to the overall population in terms of lifestyle, economy or employment. BUT the people who profit from the current energy economy will not under a renewable economy and so, obviously, they will resist. Given such people control the politics of this country (and many others) and sit on the choke points of the global economy as it currently operates, we’re not likely to embrace any such changes until we’re forced to.

Those that have such power and wealth are very unlikely to give it up willingly. Historically, in such situations force has been necessary and there’s no reason to think it won’t be this time. That’s the liberal dilemma: embracing peace and reason as a weapon against such conflict is very unlikely to be successful. And, of course, everyone with the education and resources to be effective in the fight for change has an undeniable vested interest in the system maintaining the privilege that granted them their education and the leisure time to worry about global problems, a life they’re unlikely to risk on a fight to protect the welfare of future generations or those unable to afford the mobility or imported food or air conditioning (or heat) that a changed global environment will make their new survival issues.

Those struggling to survive due to the new environment are unlikely to have the resources to do anything about it. Plows and water Buffalo aren’t going to make much of an invasion force against Washington.

It is trivially possible to avert this disaster. We will not until it’s too late, but we could if we wanted to. There are far better means by which we might make use of combinations of renewable and, when most efficient, some non-renewable resources to live within a reasonable per-capita planetary carbon (and other pollutant) and energy budget, but if we take an extreme case we could convert the entire global energy budget to photovoltaics. To do so would be reasonably affordable, and could be done without risk, and easily.

Here’s the basic math.

Lets say the whole world wants to use as much power per capita as the US does (and they do, and will if they aren’t bombed into submission). If we continue to use all the carbon based fuels in the planet, including methane hydrates, we have enough for 60 years. If we use all the uranium, it adds 6 months. Uh oh.

Best case is that we safely burn all the methane and oil to bring everyone up to the living standards we enjoy:about 20Tonne CO2 equivalent per capita for the US. The world average is now 4.2T per capita per year, though the world seems to be able to absorb only about 1E10T of CO2 per year. That means the world can support only about 500,000,000 (5E8) people on a carbon economy at our current US standard of living (or twice that at the European standard of living). Somehow we would have to convince 5,600,000,000 (5.6E9) people that for the good of the remaining 500,000,000 (5E8) they have to shuffle off this mortal coil so we may continue a carbon economy. (Or 95% must continue to live poor so we can continue to live rich – which has been the professed principle of US foreign policy since before WWII, not surprising since the math is pretty straightforward).

We sure are damned if we do.

A 16kWh/day (5.8E3 kWh/y) complete grid tie system costs $15k (these work out to 12% efficiency panels). 2E10 of these systems would power the whole world (volume discount?) or $3.1E14 which is roughly the GDP of the world for 7.5 years.

Now figure you’re asking BP to manufacture 4E11 solar panels… that’s 400,000,000,000 panels. Perhaps there’d be a volume discount. Perhaps there’d be some competition for the business? Prices would probably drop.

So lets assume typical cost reductions for volume manufacture and a combination of PV and solar heating: the world uses 1.2E14 total kwh/year for all purposes, but only 1.3E13 kWh global consumption of electricity. So if we replaced only electricity consumption for the whole world with PV at RETAIL prices it would cost only 70% of the world GDP for one year, and require only 4E10 panels, or 5.6E10 square meters of land area – out of 1.3E14 square meters of land area available in the world or 0.04% of the planet (0.4% to replace all energy consumed for all reasons with PV). So much for covering the planet.

The US used 2.8E13 kWh total energy in all forms last year (3.6E12 kWh electricity) which would require 9.6E10 solar panels or 1.3E11 square meters and $7.2E13 at retail. This would occupy 1.4% of our land area of 9.4E12 square meters.. We’ve paved 1.6E11 square meters: that is we’ve already given 1.7% of the total area of our country to our cars, more than it would take to be entirely energy independent. No more wars in the Middle East.

Continuing the car comparison, our roadways, all taxpayer financed at a cost of about $2E6/lane mile, or roughly $340/sq meter, cost $1.9E13 in today’s dollars (spent over the last roughly 80 years), compared to $7.2E13 to convert the entire country’s entire energy use to PV. Realistically we’d only convert the all the electrical consumption of 3.6E12 kWh at only $9.3E12 at RETAIL prices for TODAY’s Panels. Can we convert to solar by federal fiat? We spent 10x as much to push people off trains and trolleys and into cars at the behest of Ford and Goodyear.

Are damned if we don’t (or do solar instead?)

Perhaps the effect of covering a percentage of the planet with solar panels would be a problem? Taking all that sunlight out of the heat stream to generate power (as some suggest)? Or adding dark panels that heat up in the sun rather than cool green trees (as others do)?

The first contention is absurd since solar power as proposed is a steady state system so the net effect is limited to the difference in the albedo of the world as a consequence of putting up solar cells (the 90% of incident energy NOT converted to electricity). If we converted all that energy to hydrogen and thereby took it out of the global energy stream, we would sequester about 1/2 the amount of energy all plants do. Global warming is currently adding about .04W/M^2/year to the captured energy load which is in increase of 1.7E14kWh/year. If we diverted all the captured solar energy into storage, the net environmental effect would be about the same as the difference between now and four years ago due to increased greenhouse capture.

The effect of the second concern, the albedo change, would be about half the consequences of the paving we’ve already done. We’d add 1.5E12 square meters of cells, adding 2.2E15 kWh/year heat load due to albedo changes, compared to 1.1E16 kWh/year heat load added by global warming since 1850, a net 80% reduction for 20X the power we’re already using worldwide, and thereby bringing the entire population to US per capita standards.

No, we would not be damned by converting to solar.

As I said, converting the whole planet to PV doesn’t really make sense. Some areas have easy access to wave power, others to wind power, some are better suited to thermo-voltaic towers, others to extracting heat from deep, dry rocks, others to extracting heat from geothermal vents, but this only amplifies the argument. There are no net penalties for the planet to stop using oil. The penalties only accrue to those who profit from the $4.4E11 the world will spend on oil this year.

It is just too bad that those people are in charge…

Posted at 03:35:10 UTC

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