An addendum to my original panicking-about-climate-change post: If we really are to reduce the presence of greenhouse gases in the way we may have to, it may take turning our cities into true concrete jungles. On to weaning ourselves off fossil fuels. I gave up on a couple of fronts Friday without making any real recommendations, but I'm doing no giving up today.
As in my last post, I begin with some notes from the EPA report cited in that post. First, some notes on fossil fuels in general. T. Boone Pickens is right about one thing: natural gas is less carbon-producing than oil. Natural gas has 45% less carbon than coal, compared to 25% for oil. Problem is, at every stage of natural gas' journey from the ground to the pump it leaks methane, as mentioned above, a problem that also exists to a lesser extent with oil. As we'll see, there's a good reason Pickens wants to fuel our cars with gas while proposing powering America with wind. The vast majority of fossil-fuel-burning electricity plants are coal plants, although there are a number of natural gas plants as well.
In addition to using fossil fuels, this Wikipedia article lists the following methods of generating electricity: nuclear (fission and theoretical fusion), wind, solar, wave/tidal, geothermal, biomass, and hydropower. Any or all are feasible for generating electricity to some extent or another.
Nuclear power, proponents claim, doesn't have any carbon emissions and isn't going to tie us down to countries that don't like us. Unfortunately, it is VERY controversial. The spectre of Chernobyl and Three Mile Island still hovers over many Americans, and even discounting the idea of a cataclysmic disaster, there is still the problem of waste disposal. Nuclear waste will likely remain deadly radioactive for thousands of years, and it's damn near impossible to keep people from cracking it open in the meantime. Nuclear reprocessing is an iffy technology at best. And then you have to make sure the uranium doesn't get into the wrong hands. And it's not completely non-carbon-producing either. Oh, and the uranium will eventually run out. Basically, way way way too many concerns here. But if we can get fusion going, it should be accident-free, with very little risk of weapons proliferation, any radioactive products would be radioactive for far shorter spans of time, with no global warming risk, only a need to contain tritium byproducts.
Wind power is clean and safe, will go on as long as there's wind, and the only real resources used are in construction of the turbine itself. It does need to be placed in windy environments, doesn't look like the best thing in the world, and could pose a threat to birds, but at 2006 rates would cost only a teensy bit more than coal and gas (and nuclear a bit higher than that). The downside is that the capacity of an individual wind turbine is half a megawatt or less, but they're typically combined over a wide area. You can see why T. Boone Pickens is high on wind power, and it could be a rather simple proposition.
Solar is similar to wind. There's no emissions and the only resources used are in construction of the panels themselves, and if the sun ever stopped sending energy down to us, losing our source of electricity is the least of our problems. Again, it would work best in areas that get a lot of sun year-round and not a lot of clouds, which mostly means tropical areas. The main knock on solar is its expense (far more than for anything covered to this point), but the price keeps coming down. (To a lesser extent, proper power storage for nights is a bigger problem.) Often it's possible to get solar panels for your house, which - especially if instituted in the building process - doesn't have to look unsightly, and which has been known to pump electricity back into the power grid.
What would be cheaper than standard solar panels is using an ordinary (albeit gigantic) parabolic mirror to concentrate solar energy at a focal point (or a bunch of ordinary mirrors all focused on that point) where the pure heat generated can be harnessed somehow (possibly, indeed probably, in a way that also solves the storage problem - but could require continued resource use). There are people who think a few concentrated-solar fields in the middle of the desert could solve all the world's energy needs at little cost or global warming contribution. We almost don't need to move on to the other sources!
(Although it might cost a mite too much to build and maintain a transmission grid to bring that energy to every corner of the continent... and it might make the countries that house the solar plants disproportionately powerful, bringing us "OPEC rules the world" all over again. Fortunately, one of those could be the California desert, which is already a center for the technology. And it's worth noting that standard solar panels can similarly benefit from being placed in the desert. Slap some solar panels on enough buildings in cities like Los Angeles, Las Vegas and Phoenix and you could be powering much of the West Coast.)
Wave power is basically trying to harness the power of ocean waves, and obviously are limited in where they can be located, as they need to be placed out at sea, preferably in temperate zones. They're also currently expensive and woefully inefficient, but the only resource use is in construction. As technology progresses, wave power might be a viable option, and should remain available as long as there's wind. Tidal power is similar in many ways, and often resemble undersea wind operations. It's a very new technology that's still being worked on. (There is an older form but it's become rather controversial. I don't know, however, how the current technology might affect fish populations.)
Geothermal power looks to tap the earth's internal heat to generate power, and is perhaps third only to solar and wind in enthusiasm among renewable-energy pushers. Unfortunately, it has a number of problems, foremost among them for our purposes being that it still emits greenhouse gases, albeit fewer than fossil fuels. They can be pumped back into the earth but it still results in more emissions than the "none" from wind, solar, wave, and tidal. Also, it's by nature inefficient, it runs the risk of contaminating nearby water with dangerous substances, and it's not truly renewable, as overworking the site may require it to scale down production eventually. So that's not good enough.
Biofuels are not talked about much for electricity generation, but it's worth talking about them anyway. Biofuels still emit carbon dioxide when used as fuel, but it's carbon dioxide that would have gone into the atmosphere anyway (possibly with methane along for the ride). It's also carbon that the plant attained throughout its life, helping offset its own later release. (However, there may be concerns regarding whether it really is a net wash or gain.) For most plants, there are concerns that food prices could go up (which may already be happening), especially with how high population levels are rising, and the famed Brazilian sugarcane-ethanol program has raised concerns that rain forests could be chopped down to make room for cane fields.
The ideal solution would be to engage in a form of biofuel that wouldn't rob the food supply and possibly wouldn't require any new production at all. (If we made biofuel from a plant that wasn't fit for human consumption, do you plant the food crops or the fuel crops? This is a problem with the much-ballyhooed "cellulosic ethanol".) There's some interest in using biomass waste to produce energy (which would also stop the waste from being dumped into landfills), but is there enough of it to meet our energy needs? Harvesting algae for fuel also shouldn't rob our food supply, at least too much. So that's an idea with promise, although once again it's a ways from reaching the market, and there is some significant strain involved as demand rises.
Finally, hydropower dams don't use any resources but are location-dependent. More importantly, they can do a whole mess of harm to local ecosystems, and floods from reservoir creation can cause plants to give off methane and carbon dioxide, not to mention displace local populations. Also, dam failures can be catastrophic. If a wind or solar installation is the target of a terrorist attack, the only impact is the loss of power. If a dam is destroyed by terrorist attack, there's a bit bigger problem to deal with.
What about "clean coal"? To hear most environmentalists speak of it, it's little more than a con, woefully inefficient and vulnerable to the slightest failure.
So, solar energy alone can take care of most of our energy (here = electricity) needs with a clear conscience, with the rest to be taken care of by wave and tidal installations offshore (pending those technologies getting further developed) and wind farms in the heartland and in mountainous areas. We can get cracking on solar and wind installations right now, and we should. So we can meet our electricity needs without relying on fossil fuels or otherwise belching greenhouse gases into the atmosphere - there's a tremendous chunk of global warming emissions right there. (And if there are any criticisms I missed I welcome any challenges to my assumptions and will freely change my opinions if there is any new information.)
Can these same sources reduce our use of fossil fuels in other areas?
According to the EPA report I linked to Friday the main use of direct fossil fuel combustion in industry is to produce steam or heat that can then be channeled to other purposes. Residential and commercial uses are primarily for heating and cooking. We also still have transportation to get to.
The easiest thing to take care of could be heating homes and businesses - in addition to store-bought insulation you've probably heard of, solar energy can be channeled to warm any home, and an "earth-sheltered home" can also help protect you from the elements. Of course, an ounce of prevention is worth a pound of cure, so living in naturally warm climates and designing houses to let in maximal sunlight are also desirable options. (Of course, living in places like LA, Phoenix and Las Vegas also means draining dwindling water supplies.) With our new green electricity future, it's now okay to use an electric stove and/or oven to cook, which leaves gas/propane/charcoal grills (and, if you're concerned enough about ecological impacts or the theoretically-offset carbon emissions, wood-fired stoves). Solar power can help us here as well, it turns out, at least if you're outdoors. Industry could be one of the toughest challenges - beyond electricity, fossil fuels are used in all sorts of applications - but most uses of combustion not already coming from electricity could, I imagine, be replaced by electricity, old-fashioned wind or water mills, or solar power. Or biomass if you consider that to be okay.
But transportation... how to fuel our cars and trucks... that could be a problem. It's possible to drive solar, but it's unlikely you could use it to carry any sort of load, and I don't know how possible it would be to drive at night. Basically, it's probably infeasible and looks silly. Wind cars sound nice, but because wind power works best at certain locations it would be way too unreliable. Wave, tidal, and hydroelectric power are obviously out of the question. What about previously rejected approaches? I'm not allowing millions of miniature nuclear reactors without workers ready to prevent meltdown on the roads, geothermal is obviously too tied down to a specific point, and biofuel has been covered above, with the conclusion that the only biofuel I'm not skeptical about is algae-based fuel, and even then I have some misgivings about the amount of land required to grow algae.
Hydrogen, in my view, is overhyped. It may be the most abundant element in the universe but most of the hydrogen on Earth is already in water; extracting hydrogen from water in order to turn it back into water is inherently inefficient and results in a net loss of energy, it's just simple thermodynamics. Its main competitor has long been to extract it from hydrocarbons, which requires more fossil fuel use and produces carbon monoxide, which then gets converted to carbon dioxide, which would then contribute to global warming. It may be possible to generate hydrogen from certain chemical reactions or from biological processes, though, but it may be way too far away from being market ready. After George W. Bush voiced his support for hydrogen at the 2003 State of the Union address, it's basically fallen out of favor and off the radar. And even beyond the difficulty of setting up the hydrogen economy, there's the much-ballyhooed "it only gives off water" argument that undercuts itself: It turns out that water vapor is itself a greenhouse gas that mostly isn't counted in emissions totals because it has unique properties that make it hard to accurately measure its impact on global warming.
So we can't use solar, wind, or water power, we might be able to use biofuel but only a specific kind that might be a ways away from being ready and even that's iffy, and hydrogen is for next century if ever. I give General Motors credit for putting out its plug-in hybrid Chevy Volt, which will allow us to take full advantage of the "greening" of the electrical grid to power our cars, and which won't need to use any oil within 40 miles. Only super-long commutes and long-distance trips would need to use an oil engine, and having electric-charging stations every 40 miles or so along major routes could solve that problem. But it looks to cost over $30,000 and possibly close to $40,000 (before government tax credits) - a fully-electric vehicle might be cheaper but might also substantially increase the load on our new green electric grid, requiring more solar power generators, more wind farms, more offshore wave/tidal facilities.
What if there was a form of transportation that would use almost zero resources on a per-person basis? One that would be clean for the environment and won't tie us to hostile nations, while also saving us loads of money? Sound overly optimistic? It's possible, and in some places it's already here... but it might require a substantial rethinking of the way we live and the way we perceive American cities.
I'll reveal what it is later in the week and possibly (probably?) as soon as tomorrow.
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