Back in the ’70s, we experienced what I’ve been snidely calling the Energy Crisis Lite. A small group of oil suppliers stopped selling us their stuff, and we went into such a panic that we even started buying fuel-efficient cars. Then those suppliers decided our money was as green as anybody else’s, so they resumed selling us all the oil we wanted.

Choosing a gas station to attempt to control the source of your gas is moot:

Can I Tell Which Companies Purchase Imported Crude Oil or Gasoline?
While EIA cannot identify which companies are selling imported gasoline, we do collect data on which companies import crude oil and refined products. However, the fact that a given company imported crude oil or gasoline does not mean that those particular imports will end up being sold to motorists as that company’s brand of gasoline. This is because gasoline from different refineries is often combined for shipment by pipeline, and different companies owning service stations in the same area may be purchasing gasoline at the same bulk terminal.
—US Energy Information Administration, “Oil Imports and Exports – Energy Explained, Your Guide To Understanding Energy”

Oil is a fungible commodity, so what matters to price is the world demand. (And world oil futures speculation and local distribution costs…)

Since the forwarded message makes such a point about not supporting Saudi Arabia: ~8.7% of oil used in the US is from the Persian Gulf, including ~5.3% from Saudi Arabia. The top sources of oil used in the US are:

The numbers in the email for which companies import oil from the Middle East are also wrong. For example, it lists Valero as importing no Middle Eastern oil, when in fact the Persian Gulf is the source of 24% of their oil. BP is also quoted as 0%, when it is actually 10 or 44% depending on the region. The email also lists Amoco as an importer from the Persian Gulf, when it is a division of BP, which it lists as not an importer from the Persian Gulf. Several others on the list of 0% each only supply fractions of a percent of US oil. Besides, as shown above, the original source of the oil doesn’t matter to price. Even if we could shift where we get our oil, that just shifts who is buying from where, with the total sold remaining constant.

What matters is the total oil used. A quick calculation shows that to decrease the amount of oil used in the US by the amount we import from Saudi Arabia, all you have to do is increase average fuel economy by a bit over one mile per gallon. Most people can improve their mileage by more than that by just learning to drive their current car slightly better. In fact, we may get there before most people learn to drive properly: last year’s update to the CAFE standards finally started us back on track to improve fuel economy by more than this amount.

Remember, the solution is efficiency, not which gas station you buy from!

After I wrote this, I found that a variant of this particular email has been around for years, and that Snopes debunked it six years ago.

Hmm… maybe I should debunk some of The Heritage Foundation’s claims about oil prices too…

A gallon of gas contains an average of 36.6 kWh. So, if a car gets 25 miles a gallon, it uses 1.46 kWh per mile. So, driving a car one mile is equivalent to keeping a 60 W light bulb on for 24.4 hours. Over one lightbulb-day per mile!

Next, I plotted this equivalency for a wide range of fuel economies, highlighting three locally common cars:

Of course, we (mostly) switched to compact fluorescent bulbs years ago. CFLs use less than a quarter of the energy of an incandescent bulb, and my car does better than 25 mpg; so, for me, driving a car a mile is more like keeping a bulb lit for over five days. Woah.

Anyway, it is an interesting paper showing that many people underestimate the energy consumption of power hungry devices, and overestimate the power consumption of small devices. It’s open access, so you should read it.

Suggested reading: ‘Public perceptions of energy consumption and savings’ (doi:10.1073/pnas.1001509107)

The the definition of light truck in the CAFE standard includes many SUVs and vans. Pickup trucks, SUVs, and vans made up around half of the passenger vehicles sold in recent years. The orange line shows the expected average fuel economy for the current mixture of trucks and cars. Keeping this mix of light trucks and cars will result in the average fuel economy only reaching 33.7 miles per gallon. Reaching the target of 35.5 mpg requires the fraction of new vehicles sold classified as light trucks to drop from one half to around one third. This is shown by the pink line.

From my estimate of the total number of cars and miles driven, I can estimate the gasoline burned, giving the CO₂ produced by all cars and light trucks on the road:

This shows the expected change with and without the new CAFE standard. For the base scenario (without the CAFE update), I included the expected change in the fraction of trucks sold. Notice that after the CAFE standard is constant, the expected CO₂ output resumes its climb. This is due to the predicted population increase, with the number of cars per capita remaining constant. The CAFE update will bring the expected CO₂ production from cars to below 2000 levels for nearly three decades, when population growth catches up with efficiency improvements.

Since I found the expected gasoline consumption with and without the CAFE update, it is easy to find the expected savings in CO₂ emissions:

Notes: The numbers from 2005 to 2010 are estimated based on 2004 levels. These years are estimated because accurate statistics are released a few years late. The scenarios not labled ‘current trucks’ include a decrease in the truck to car ratio starting with 1:1 in 2008 and reaching 1:2 in 2016. The data before 1979 isn’t as accurate as the 1979 to 2004 data, but the effect is negligible after the early ’80s due to the high turnover rate of miles driven.

Together, EPA and NHTSA estimate that the average cost increase for a model year 2016 vehicle due to the National Program will be less than $1,000…. over the lifetime of a model year 2016 vehicle, the consumer’s net savings could be more than $3,000. –EPA.

Here is a plot of historic US fuel economy along with the new standards. The historic data is based on the efficiency of cars sold each year and car survivability and miles driven by age. The plot shows all cars on the road each year, not just those sold that year. The future lines are directly from the new standards. Because the number of new cars sold is large, and new cars are driven more than older cars, the plot ignores the small hysteresis for future fuel economy. Data from 2005 to 2010 is estimated.

The various documents related to the ruling contain lots of interesting and useful information. For example, a good compilation of existing technologies that improve fuel economy, with an analysis of cost and efficiency changes. Some of these changes reduce manufacturing cost and improve fuel economy. I’ll probably use these reports frequently. They contains lots of information that I previously had gathered from many sources, as well as some I had calculated or planned to calculate.

This is certainly nicer than the standard three phase light, but I’m not convinced that it is practically better than a four phase light. I prefer the simplicity and reliability of a four phase signal to the extra complication and unneeded detail of the Stanković signal. Still, it is good to see someone else promoting the idea of better traffic signals. I’m not sure how many American drivers are alert and courteous enough to take advantage of better signals, but there are probably enough that we could still see some improvement in traffic flow, saving gas.

Source:
A Better Understanding of Stoplights through A Stoplight for the Progress Bar Generation

The four phase system is superior. The fourth phase gives drivers advance warning before the light turns. This lets everyone know when traffic is going to start moving. Drivers have time to shift into gear, and can start driving almost as soon as the light turns green. This helps eliminate the slinky effect we see at every light in the US. Here the typical situation is: the first driver is not paying attention, and takes a while to start, then the driver behind takes a while to start, and so on. If there is much traffic, these delays can make it so that only the first few cars make it through the intersection. When people are talking and texting on cell phones, it is even worse. In Sweden, everyone can see that the light is about to turn green, so they can be prepared to start before the light turns. Everyone can start at almost the same time, allowing more people through the light. This contributes to a smoother flow of traffic than we are used to in the US.

Smoother traffic flow means that the same speed limit (set by light timing) produces higher average speeds. Hard breaking and hard accelerating with traffic lights leads to lots of time spent stopped. The increased awareness provided by the fourth phase allows everyone in line at a light to start over a much shorter time, lowering the time spent stopped. By lowering the time spent stopped, the average speed of traffic increases. This means you can get where you are headed sooner. This system has the added benefit of saving fuel in two ways. The gas burned while a car is stopped is completely wasted because in isn’t helping you reach your destination. With smoother traffic, less time is spent stopped, so less gas is wasted. The second savings is partially because of driving style. In the US it is common for a light to turn green, and the first and third car to immediately start moving. The second driver isn’t paying attention, and takes a while to start. This causes the third driver to slam his brakes on. The second driver then starts moving, then the third can start again. Driver two’s inattention has cost him gas, but has cost driver three even more gas. The delay also slows all drivers behind, wasting more gas. By giving advance warning the light is about to turn, it is easier for traffic to start smoothly and keep flowing.

A four phase system should also improve safety. With traffic flowing faster and more smoothly, there are fewer chances for a driver to rear-end a car stopped at a green light. There are other potential ways for this to improve safety, but most require an improvement in driver attitudes in addition to better traffic engineering.

Since I began telling people about four phase traffic lights, I learned that there are a few in Maryland and southern Pennsylvania.

It would be really fun to prove that four phase traffic lights are superior, but time is limited, and I’m sure someone else has already done the work. Even without rigorous demonstrations, I’m sure that switching to four phase signals is a simple and inexpensive way to improve the flow of traffic, and will have a short payoff period.

New York Times: China Is Said to Plan Strict Gas Mileage Rules

You should also read Thomas L. Friedman’s latest editorial. It is past time for Americans to get serious about energy efficiency.