[URBAN NOTE] "The Mismatch Between Population and Mass Transit In the San Francisco Bay Area"

[rfmcdpei]

Geocurrents' Martin Lewis has a post up that takes a look at population density in the San Francisco Bay Area and its intersections with mass transit. I thought it worthwhile to highlight it given the critical importance of population density in debates on transit in the Greater Toronto Area.

A sound urban system, environmentalists now argue, is

Comments

[mmcirvin]

If that were universally true, rents would be low in center cities. But they're not; they're sky-high, and the real estate there tends to be fabulously expensive, with house prices dropping off in distant ring suburbs. That suggests to me that somebody does want to live in high-density areas, though not everybody does.

I grew up in a suburb and I live pretty far from the center of the metro area now. There are nice aspects to it that I won't deny. But the huge disadvantage is that I spend something like two hours a day just driving around, much of that sitting in freeway traffic jams.

Now, for much of my professional life there was no way out of that, no matter where I lived, because the employers in my industry had, themselves, all moved out to office parks in distant ring suburbs; if I lived in the city, I'd just have to figure out ways to get out of it to go to work.

But these days, tech industry seems to all be moving back into the core, around Kendall Square and in Boston. If you live in Cambridge you can have a 15- or 20-minute commute by subway. That's worth something even apart from any other attractions of urban life.

[robby]

The article seemed to promote high-density blocks of housing surrounding suburban train stations. I'd like to see a future shift to nuclear power, with plenty of hydrogen generated to power internal combustion vehicles. Some of these environmentalists seem to want to limit us, when we presently have the technology to instead provide a high standard of living.

[mmcirvin]

I really like the Do The Math blog's summary of the energy situation:

http://physics.ucsd.edu/do-the-math/2012/02/the-alternative-energy-matrix/

There aren't any really magically good alternatives to fossil fuels, though there are several OK ones. I think thorium-cycle breeder reactors are probably a great possibility for the very long term. But that's a technology that is still in its infancy and will take a lot of time and capital to ramp up. Same with hydrogen cars, electric cars, etc.

The big surprise to me, given my perceptions from the 1970s and 1980s, is that large-scale solar power is actually looking more doable than many of the other options. It has one big problem, which is that it's too intermittent for baseload grid power without some kind of buffering technology, which is a whole matrix of imperfect alternatives in itself. (On the other hand, if what you want is to generate hydrogen to power cars, that is a buffer in itself; intermittency isn't a problem!)

I suspect that the big niche for algae-based or cellulosic biofuels is going to be aviation, because it's hard to get that kind of energy density for a lightweight power plant any other way.

I guess my personal attitude is that there's little reason to reject any plausible approach outright; we may need new energy sources and changes in land use and more efficient devices, etc. Personally, I'm fond of dense development with well-planned mass transit and I don't find that situation unpleasant; currently, in North America, there's actually an undersupply of such places to live relative to demand. So I don't much worry that people are going to have to be tyrannically forced to live that way.

[mindstalk]

It probably takes more than 10x as much energy to generate fuel for cars as it does to provide electricity for mass transit. And car use is already 25% of our energy use, so we'd be talking about not just replacing our existing electricity generation but expanding our total energy use by 2.5 times. The future you want is very expensive. Especially since hydrogen would need new cars and infrastructure. Synthesized hydrocarbons would drop in better, but take more energy.

[robby]

No, with enough of the proper reactors, we can produce massive amounts of cheap hydrogen during non-peak electric demand.

[mindstalk]

"enough reactors" is expensive; you'd still have to overbuild. There's not enough non-peak surplus otherwise. And hydrogen isn't cheap to store or transport.

[robby]

Don't talk about overbuilding when the last reactor in the US was built in 1977. A good goal would be energy independence for the US, and an end to burning fossil fuels. Think of the construction jobs, and the economic effect of a domestic energy industry.

[mindstalk]

You missed the point.

The US uses 3 terawatts of energy. Much of that is wasted in heat engines, especially for making 300 GW of electricity and driving cars. (And what isn't wasted is largely burned directly for heat.) A fully electrified US, using mass transit and heat pumps, could get by on 1 TW of electricity, so we'd have to build 1 TW of nuclear reactors, minus the ones (and the hydropower) we already have. Filling all the cars instead will take another 2.5 TW, maybe down to 2 if you use off-peak power as you suggest.

None of this is about nuclear power being good or bad; the same point would apply to solar or any other clean source. The point is that 100 Joules of electricity makes maybe 33 Joules of fuel which does maybe 10 Joules of work in a car which is itself grossly energy inefficient compared to rail transit.

Independence is great. But independence and keeping those cars will take 3 times as many reactors. And the newly approved nuclear reactor is $7 billion per gigawatt, so we're talking the difference between $21 trillion and $7 trillion.

[robby]

Hydrogen powered internal combustion is an workable, easy substitute for existing technology, and I don't see electric powered rail (or electric cars) as a nationwide solution. It would work in large cities and maybe someday with high speed rail. With enough reactors, we would have plenty of cheap energy, enough to make enough hydrogen to replace gasoline.