Saturday, May 31, 2008

Big Hybrids

GM has had disappoining results selling its Tahoe and Yukon hybrid SUVs. It planned to sell 12,000 this year, but so far has sold only 1,100 through May. Fuel consumption is claimed to be 20 mpg vs. 14 mpg for the gasoline versions. Environmentalists may scoff at the idea of a green SUV, but consider this. At 14 mpg it takes a little over 7 gallons to go 100 miles, at 20 mpg this drops to 5 gallons. To get the same saving relative to a small sedan which does 30 mpg (3.33 gallons per 100 miles) you would have to switch to a scooter doing 85 mpg.

It would be nice if SUV drivers could be persuaded to drive smaller cars. For my part I cannot understand why anyone would want to drive one, for many reasons unrelated to gas mileage. But if for some reason people want them, SUVs are the low hanging fruit when it comes to energy saving. We should see a number of diesel SUVs soon, but in the mean time it is a real shame that hybrid SUVs are not selling better; the Prius drivers among us should encourage the SUV guys to go green rather than looking down their noses at them.

Friday, May 30, 2008

Two New Reports

The first is from the Brookings Institution. The report (click here for PDF) quantifies transportation and residential carbon emissions for the 100 largest U.S. metropolitan areas. Not surprisingly, the report finds that the carbon footprint of the average city dweller is substantially lower than their rural compatriots. More surprisingly perhaps, the carbon footprint of city dwellers is also increasing more slowly than the national average, 7.5% between 2000 and 2005 compared to 9% nationally. The fact that it is still increasing rather than decreasing is depressing though.

The report also found that per capita emissions vary widely between cities, largely due to the availability of public transport and the fuels used for electricity generation. Each of the 10 metro areas with the lowest per capita electricity usage hailed from states with higher-than-average electricity prices. The report also made the following policy recommendations:

  1. Promote more transportation choices to expand transit and compact development options
  2. Introduce more energy-efficient freight operations with regional freight planning
  3. Require home energy cost disclosure when selling and “on-bill” financing to stimulate and scale up energy-efficient retrofitting of residential housing
  4. Use federal housing policy to create incentives for energy- and location-efficient decisions
  5. Issue a metropolitan challenge to develop innovative solutions that integrate multiple policy areas

The second report was released reluctantly (in fact, in response to a court order) by the federal government and is a summary of recently published research on the effects of climate change on American life, including agriculture. Click here to download the full report, which is about 270 pages long. (I found the 2.75MB download very slow, perhaps because it is a popular download, or perhaps because the government deliberately put it on a slow server. The ability to download just the 17-page executive summary would be welcome.)

After reciting the evidence for climate change, the executive summary refers to the conclusions of previous government reports that “it is very likely that temperature increases, increasing carbon dioxide levels, and altered patterns of precipitation are already affecting U.S. water resources, agriculture, land resources, biodiversity, and human health, among other things” and that “it is very likely that climate change will continue to have significant effects on these resources over the next few decades and beyond.” It then goes into more detail about the effects on agriculture, health etc.

The report identifies benefits as well as costs and some of the conclusions are almost laughably obvious; for example the report predicts a decrease in energy used for heating and an increase in the energy used for cooling and that more people will die from the heat while fewer will die from the cold. (The point about energy use is not entirely trivial however, since while we use electricity for cooling we often use natural gas for heating.) While far from alarmist, the overall picture painted by the executive summary gives ample cause for alarm.

The body of the report is packed full of information for those interested in the details, including geographically detailed historical information about changes in precipitation, temperature etc. over the past century.

Monday, May 26, 2008

Pressure Sensing Valve Caps

A few months ago I bought my wife a set of pressure-indicating valve caps from TerraPass. These contain a red LED which flashes when the pressure in the tire is more than 4 pounds below the correct pressure, which is preset the first time you attach them to the valve. I bought them primarily because my wife had suffered two flat tires in a short period. Both times the tire was destroyed and she was convinced she had driven a significant distance with them partially deflated. She says she cannot tell whether they are inflated properly or not, and indeed it is impossible to detect under-inflation visually until it is quite extreme. Modern tires have much firmer sidewalls than the cross-ply tires of old, so the pressure has to get down to about 10 pounds per square inch or less before under-inflation is obvious. This is exacerbated in the case of my wife’s Subaru Legend GT Wagon by its low profile (45 series) tires.

Driving with under-inflated tires is dangerous, and – more important at least in the context of this blog -- even a relatively small loss in pressure increases fuel consumption. Fortunately we have not yet had cause to see the new valve caps in action, though I did test one of them by deliberately deflating the tires. They have the potential to pay for themselves quite quickly in saved gasoline.

Saturday, May 24, 2008

Sign Petition on Gas Tax Holiday

I have blogged before about the gas tax holiday proposed by Clinton and McCain. It sends a bad message but in fact my main objection is that it is stupid; since there is little scope to increase supply, the benefit would go to the oil companies as the price at the pump adjusts to the current price to balance supply and demand. In fact, now would be a good time to increase gas taxes, for the same reason; it would not affect retail prices in the short run, but would send a message that high gas prices are here for the long term.

To sign a petition on this go to

Monday, May 19, 2008

Double Pane Window Update

Just a quick note about the first few weeks with the new windows mentioned last month. The latest electricity bill is 40% less than the average for the same month in the previous 3 years. There is obviously a lot of variability between years due to different weather etc. but I think this is very promising, especially as the bill includes only about 3 weeks with the new windows.

I also think the house is more comfortable; a bigger temperature gradient across the window means smaller temperature gradients inside the house, so the whole house is closer to the temperature at the thermostat.

Wednesday, May 14, 2008

Hollow Victory for Polar Bears?

AP reports that the Interior Department has agreed to list the polar bear as an endangered species. It has been widely thought that such a listing would mandate the department to take action against global warming, but Interior Secretary Dirk Kempthorne does not seem to see it that way. He cited dramatic declines in sea ice over the last three decades and projections of continued losses. These declines, he told a news conference, mean the polar bear is a species likely to be in danger of extinction in the near future.

But he also said that it would be ''inappropriate'' to use the protection of the bear to reduce greenhouse gases, or to broadly address climate change. Reflecting views recently expressed by President Bush, Kempthorne said the Endangered Species Act was ''never meant to regulate global climate change,' and that the decision to list the bear includes administrative actions aimed at limiting the impact of the decision on energy development and other climate related activities. I must say this leaves me confused, and I suspect we will need to wait for the next administration to act.

Nissan Promises Electric Car by 2012

Nissan announced yesterday that it planned to offer electric cars to a small number of fleet users in the US in 2010, followed by full scale sales to the public by 2012. Carlos Ghosn, chief executive of both Nissan and Renault, said that market pressure from consumers for green vehicles was a more powerful influence than government regulation.

Nissan has been perceived to be behind other manufacturers like Toyota and Honda, but no company has made such a clear commitment as Nissan made on Tuesday. It should not be a surprise, though. Nissan’s partner, Renault, had announced its part in an electric car project supported by the government of Israel. (See my posting on February 13th 2008.) The range of the vehicles announced then was only 40 to 70 miles, and the plan was to provide stations where quick battery changes could be made, rather than waiting for them to be charged.

The new news in yesterday’s announcement is therefore that electric cars will be marketed in the US. There was no mention of the range, which I think would need to be quite a bit better than 70 miles for the cars to be generally viable.

Tuesday, May 13, 2008

Climate Skepticism Increases

On April 25th I posted a comment about how it was going to be difficult to sustain belief in climate change over the next few years because of potential short-term cooling effects due to cyclic factors, namely La Nina and sun spot activity. Today the NYT reports that a recent Pew survey showed belief in global warming slipped from 77% in January 2007 to 71% in April 2007. I am not sure they asked the right question, however. An informed person might well say that he did not believe there was “solid evidence that the earth is warming,” precisely because of the short term effects already mentioned. A better question would be whether there solid evidence that the earth will warm.

Apparently the decline is mainly due to Republicans, among whom affirmative answers to the answer to the question declined from 62 to 49%. I am not sure why this should be a party-political issue, but it is ironic that it came out the same day as John McCain gave his most emphatic support to date for a cap-and-trade system to limit greenhouse gas emissions.

Friday, May 9, 2008


Well, the Offshore Technology Conference finished yesterday and I feel slightly less depressed. Offshore generally refers to offshore exploration and production of oil and gas, but it turns out that a lot of the technology is applicable to offshore wind farms and to hydrokinetic sources from waves, currents and tides. The reason for this is that the biggest challenges are not so much the turbines and whatever but the methods used to plant or tether the equipment at sea, and also getting the electricity (as opposed to the oil or gas) to shore. There were conference sessions on renewable energy, “CO2 security” and CO2 sequestration, but these were very much in the minority.

I went to a breakfast session put on by the UK Trade and Investment group and was impressed at all the ideas out there to harness wave power in particular. The Scots in particular have ideal offshore sites for both wind and wave and seem to see these industries replacing employment in the declining North Sea oil wells. They even have a test site where anyone with an idea can not only test it out but plug into the grid and sell the electricity.

Monday, May 5, 2008

Offshore Technology Conference

It’s OTC time in Houston and everyone in the oil business is in town. I went to a welcome reception last night which was preceded by five industry presentations. Most of the presenters started off paying lip-service to climate change and the need for conservation and for renewable energy sources, and also for Houston to become the “Energy Capital” of the world instead of just the “Oil and Gas Capital,” and then went on to say how many billions of barrels of oil there was left to exploit. Quite depressing, and maybe I should give them some slack in view of their target audience, but I have to think the current guard at the oil companies needs to retire.

One presenter described how the next phase in the Gulf of Mexico is Tertiary deposits which are not on the continental shelf but way off shore in water which is 15,000 feet deep and the oil itself another 35,000 below that. It is also at 400 degrees (Fahrenheit or Celsius?) and under unprecedentedly high pressure. In spite of this pressure, they would still need pumps to get it to the surface because of its depth, and all this presented enormous technical problems. For example, new materials will be needed to withstand the temperature and pressure. Then of course there are the hurricanes. One has to wonder whether the billions which will be spent on this technology could be better spent on renewables.

The experience reminded me that high oil prices are a 3-edge sword. On the first two hands, it encourages consumers to conserve and entrepreneurs to come up with alternatives, but on the third hand it makes it economic to pursue more and more inaccessible sources of fossil fuels. Next time someone tells you that wind power is capital intensive, remind them that oil is getting increasing so too.

Saturday, May 3, 2008

Voinovich Bill

Senator George Voinovich has introduced a bill to the senate which purports to be a global warming measure but which is a lot weaker than most people think necessary. For more details and to take action see

Thursday, May 1, 2008

Why Tax Holiday Won't Work

Both McCain and Clinton have proposed a gasoline tax holiday for the summer. Fortunately for the environment, it won't work.

McCain, whose idea it was first, admits he does not understand economics, but Clinton should know better. There is very little short-term elasticity on the supply side, so the price at the pump is determined by demand. This price won't change much if there is no tax; rather the money which would have gone to the government will go to the oil companies. Which is ironic, given Clinton's idea of a windfall tax on these companies.

So, it's bad for the federal deficit, makes the oil companies richer, and has little or no effect on he price at the pump. And to the extent that it does reduce prices at the pump, it is bad for the environment.