Monday, March 31, 2008

Majority favor Energy Conservation

A recent Gallop poll shows that a plurality of Americans continue to favor protecting the environment over economic growth, in spite of the slow down in the economy. Most expect the US to face energy shortages in the next few years, and a solid majority favor conservation as the best way to counter that. Full survey at

Wednesday, March 26, 2008

Green BMW

The BMW 1-series was introduced to the USA recently with 3-liter 6-cylinder engines. Unfortunately we will not get the diesel model, the 118d. As its name suggests, this is powered by a 1.8 liter diesel engine, producing 141 horsepower and 221 pound feet of torque. This is enough to propel it to 60 in 8.8 seconds, which is not exactly blisteringly fast but is fast enough for most people, and a lot better than a Prius. It was also enough to win the World Green Car of the Year award in New York this week.

The car also boasts what BMW calls Efficient Dynamics, which as far as I can ascertain comprises regenerative braking and automatic stop/start. The latter works by switching the engine off when the car is stationary and put in neutral. It restarts when the clutch is disengaged. The regenerative braking is more problematic; the regained energy is used to charge the battery, but since -- unlike a hybrid -- there is no electric motor this can ultimately be used only for the car’s electrical systems. (Which include electric power steering, by the way.) It does however reduce the demands on the alternator, which disengages when the battery is charged thus reducing the drag on the engine. I would have thought the contribution of that feature towards fuel efficiency would be small, but every little helps. And you certainly cannot argue with the overall result. The car is rated at 59mpg on the highway. (An independent test by the German magazine AutoZeitung achieved 47.9 mpg in mixed driving, compared to 39.8 for a Toyota Prius.)

My only concern was that they use low-rolling-resistance tires to squeeze a few extra miles per gallon out of the car. Such tires normally mean low grip, but in this case it seems my concern is misplaced. British magazine Autocar reports great handling and stellar braking performance; 155 feet from 70mph, which is about as good as it gets.

Saturday, March 22, 2008

Double-Pane Windows

Yesterday I ordered our new double-paned windows. This is a major investment, but one I expect to pay off in ten years even without factoring in any increase in electricity prices. Selecting the best windows is not easy though. Manufacturers quote U-value, Solar Heat Gain Coefficient (SHGC), Visible Light Transmission (VLT), and sometimes R-value and Ultra-Violet Light Transmission. I will try to explain what they all mean, insofar as I understand them myself.

As far as I can make out, the R-values and U-values are reciprocals of each other, so quoting both is redundant. They measure thermal conductivity, and as a general rule it seems that U-values are used for windows and R-values for walls and roofs. A high R-value (i.e. a low U-value) indicates a good insulator. R-values for roof insulation are typically over 10. However, the interpretation of U- or R-values for windows is problematic because heat transfer through the window is not only due to conduction, and indeed maybe not be primarily due to conduction. I think this depends upon the direction of the heat flow; it hot climates when the house is being air conditioned, a lot of the heat coming in is radiated, whereas in colder climates when the house is being heated most of the heat going out is conducted.

Living in Houston, I decided the SHGC number was the one to concentrate on. This measures the proportion of radiant energy falling on the glass which is transmitted rather than being reflected. Good windows by this measure have SHGC of .18 or .2. There is a trade-off however, in that VLT tends to be lower too. VLT numbers are deceptive however; I saw an installed window with an SHGC of .18 and a VLT of .27. It was noticeably different from plain glass, but it did not seem subjectively that only 27% of the visible light was transmitted. Note however, that even plain glass transmits only about 60% of visible light, and I think these numbers do not match our subjective experience. (A bit like decibels and sound sensations.) The glass manufacturer offers an alternative which looks like it might be a better compromise, with SHGC of .2 and VLT of .44. I have left the final decision on this until I speak to a technical expert at the factory next week.

Wednesday, March 19, 2008

Tesla in Production

Tesla announced that they have started series production of their electric car. Rather than duplicate it, here is a link to the press release.

Monday, March 17, 2008

NYMAX Carbon Market and Oil Prices

The New York Mercantile Exchange (NYMEX) opened its carbon exchange today, competing with the Chicago Climate Exchange and the markets in London. The Green Exchange, as it is called, offers trading in global carbon-based contracts, such as carbon allowances under the European Union Emissions Trading Scheme (EUAs), carbon credits under the U.N. Clean Development Mechanism, and verified greenhouse gas emission reductions used in accordance with voluntary carbon standards. EUAs closed at 21.90 euros per metric ton.

This seems almost superfluous compared with the price of oil. I think a barrel of crude is equivalent to about 1/3rd of a metric ton of carbon dioxide. And the experts don’t expect that price to come down. For the first time ever, all futures through 2016 are trading at over $100 a barrel. The Financial Times quotes Jeffrey Currie of Goldman Sachs predicting prices as high as $175 a barrel.

Meanwhile Dick Cheney is in Saudi Arabia trying to persuade them to increase their production. This is pure theater, because Cheney is well connected in the oil business and must know the Saudis’ dirty little secret; they are already pumping all they can.

Saturday, March 15, 2008

SmartStrip Saga

As previously posted, my experience with SmartStrips has been mixed. The one controlling my entertainment system seems now to be working reliably, except that there is a delay of about 30 seconds between when I switch off the controlling device (the tuner/amp) and when it shuts down the other devices. (I don't know why this is but it is not important. Maybe the tuner/amp goes thourgh some power-down procedure.)

The other SmartStrip still refuses to respond to switching the printer on and off. As noted before, the printer draws 13 watts even when off, so that would hardly be satisfactory anyway. I ended up replacing the wall socket with one with a switch and a light to indicate when it is on. The wall socket happened to be about waist height, so this just allows me to switch everything on and off without crawling under the desk to get to the power strip.

Wednesday, March 12, 2008

Blue is Green at Mercedes-Benz

On February 20th I mentioned the Mercedes-Benz E-class Bluetec diesel, available now in the US. The company made two more big announcements at the Geneva Motor Show last week. The first was that they are ready to introduce lithium-ion batteries in a hybrid version of its top-of-the-range S-class sedan next year. Dubbed the S400 BlueHybrid, this large sedan uses a 3.5 liter V6 which together with the electric motor delivers about 299 horsepower. The company claims 29.7 mpg, and the car will reach US shores in the third quarter of 2009.

This will be followed by a turbodiesel-electric hybrid version, the S300 Bluetec Hybrid, delivering 221 horsepower and no less than 43.6 mpg. Finally, this same power train will be used in a version of the GLK SUV; the Vision GLK Bluetec Hybrid will deliver 39.7 mpg. The nomenclature is a bit confusing, and I am not sure why blue is the new green in Mercedes-speak, but if verified by independent tests it will be difficult to argue with these impressive results.

Lithium-Ion batteries are used in electronic devices like laptops, where they have been known to catch fire, but this is the first mainstream application for cars. (My Tesla will also have lithium-ion batteries when they finally deliver it, while Chevrolet cites the need to perfect these batteries as the reason the Volt will not be available until 2010.) Mercedes-Benz have integrated the batteries into the cooling system to keep them at an efficient and safe temperature.

Monday, March 10, 2008

Does Daylight Saving Time Waste Energy?

I have always hated daylight saving time, but believed it could be justified on the basis that it saved energy. Now, a new study syggests otherwise.

As reported by NPR and USA Today, the study was done in Indiana where until recently most counties did not observe daylight saving. It seems that the study was based solely upon comparison of domestic electricity bills, comparing those before and after the change in counties applying daylight saving for the first time and using the counties which did not change as a control. Which makes it hard to see how it would have data to justify the conclusion like that while people saved money on lighting they spent more on heating and cooling. The study also did not consider non-domestic consumption, for example in schools and work places, so I would not regard it as definitive.

However, this is an area which warrants further study because it could be one small contribution to energy conservation and hence to combating climate change.

For the full interview with study leader Matthew J. Kotchen in USA Today see

Canada's Letter to Robert Gates

The Financial Times today leads with a story about a letter sent to Robert Gates by the Canadian ambassador about the Energy Independence and Security Act 2007. Signed into law in December, this act requires among other things that government procurement of alternative fuels cannot include those whose lifetime greenhouse gas emissions are no better than that of conventional oil. Canada is concerned about its large reserves of oil sands, which would not qualify. The letter to Gates says that Canada "would not want to see an expansive interpretation" of the act, though it is hard to see how the act could be interpreted to favor the oil sands.

Oil being fungible, it is not clear to me that prohibiting purchases by the federal government would have any effect on the overall usage the oil sands. The provision in the act seems to me to be purely symbolic, since private purchases of oil from the oil sands would reduce price pressure on other sources and the federal government would benefit from this just as if it were buying the Canadian oil itself. Canada is apparently worried that the act may provide a precedent which might be copied by state governments and other countries. I would add environmentally consious corporations.

We should not be using this oil, and Canada and the oil companies should have known this before they embarked on the enormous investment which they are now trying to protect. Unfortunately, since I think all of the major oil companies are heavily invested in the oil sands, there is not much we as consumers can do about it.

Saturday, March 8, 2008

Kill-a-Watt, SmartStrip, etc.

[Sunday, March 9th. After I posted this last night, I switched off the printer and again the SmartStrip failed to switch the other stuff off, as a reslt of which I have made substantial revisions to the posting.]

I bought a Kill-a-Watt power monitor, among other things to help me work out why the HP printer did not seem to reliably switch the SmartStrip (see last Saturday’s posting). The Kill-a-Watt fits between the outlet and whatever device is plugged into it, allowing one to measure the power used by that device. Unlike the Cent-a-Meter described last week, which measures total household usage and is very useful in its own right, this is not influenced by extraneous factors going on in the house like the refrigerator cycling on and off.

I found that the printer is quite consistent: it uses 7 watts when plugged in but switched off, and after going as high as 37 watts during its power-up sequence it settles at 13 watts when switched on. This seems not to be a large enough difference to make the SmartStrip work reliably. I adjusted it as carefully as I could, and at first it seemed to work, but as noted above it later failed to switch the SmartStrip off. I also wonder why the printer draws any power when switched off; that 7 watts costs $10 a year. Maybe time for a new printer.

I also tried using the DSL controller, which draws only 8 watts when on, as the controlling device. This turned out to be inadequate to switch the SmartStrip on, even when the sensitivity was turned up to he maximum.

I had similar trouble with the entertainment systems being switched by the tuner/amp when this was done using the remote. The unit draws 24 watts when working and 14 when on standby, and again the SmartStrip does not seem to be sensitive enough to detect the difference. If I switch off using the switch on the unit instead of using the remote it works fine, so I guess I will be doing that in future. (Saving that standby power is worth $20 a year, so I should be doing that anyway.)

The Kill-a-Watt is quite expensive at $45.95 (from but it has a number of other features. Most useful, in addition to measuring the rate of power usage in watts, it can be used to integrate that over time to measure kilowatt hours used over a measured time interval. This is perfect for monitoring things like refrigerators which cycle on and off. It can also be used to switch between active power and apparent power readings, and can also display the power factor. These are rather esoteric measures which take account of phase differences between the voltage and current, and I doubt many users will understand or care about them. Other features include monitoring voltage, current, and frequency, and again I am not sure what use these would be put to.

To test the kilowatt hour capability, I turned my attention to our ancient refrigerator and found that it used 0.16 kWh in 2 hours, so averaging about 80 watts. This does not sound much, but it is on 24/7 so over a year this is about 700 kWh. At my price of 16 cents this is $112 a year. According to the energy star site, a typical modern top-freezer 18 cubic feet energy star rated refrigerator consumes about 400 kWh per year, so replacing our old model could save about $50 a year and pay for itself in 9 years. That may not sound like a great return, but what bank is gong to give you 11 percent? And that assumes energy prices do not go up in those 9 years. Bottom line is that old fridge will soon be history.

Finally, I used the Kill-a-Watt to test some chargers. It seems almost a cliché to say one should unplug chargers when not in use, but I found this not to be worthwhile. I tried two Dell computer chargers. Both registered 0 watts when the not plugged into the laptop. When plugged into a fully charged laptop, they registered 1 and 2 watts respectively. I also tried two mobile phone chargers and found that both registered 0 watts when not charging a phone. I also tried an electric toothbrush charger and a cordless phone charger and found that these registered 0 or 1 watt even when they were charging. I therefore think one should not lose sleep over chargers.

Friday, March 7, 2008

New Gadgets at Energy Technology Venture Capital Conference

This conference, organized by the Houston Technology Center, took place yesterday and today. I did not register for the conference because I could not make the first day and today was just a half day, but I was invited to lunch today and to see the exhibits. The lunchtime keynote speaker was John Hofmeister, President of Shell Oil. I had heard him give the keynote at another conference last week, and it was essentially the same speech though it seemed more polished this time. (He gave it at least one more time in between also.) It wasn't what most climate change activists would want to hear, but at least he was unequivocal in saying that we needed a cap-and-trade system. He said it was time to stop arguing about whether climate change was real and get on with doing something about it.

More interesting to me were some of the exhibits, which I hope to cover in more detail at a later date. Here are three that caught my attention.

A Company called EnerPlus ( has a new kind of spark plug which utilizes a capacitor to greatly increase the size of the spark, resulting in more complete combustion and a claimed improvement of 6% in economy and up to 12% in power output.

A company called Adaptive-AC allows each room in your house to be controlled by a programmable intelligent thermostat built into the air conditioning outlet. The thermostat adjusts the temperature by opening and closing flaps so as to regulate the air flow, thereby balancing the temperature over the house. (Or not balancing it, if for example you don’t want A/C in the living room when you are asleep in bed.) The unit is powered by a small generator driven from the air flow, and stored in an ultracapacitor for when the A/C is off, so there are no batteries. The product is not in volume production yet. (For technology junkies, the protypes were made with a 3-D printer, which is the first application of this technology I have come across.)

A company called DBLive ( controls sprinkler systems by using the weather forecast to generate soil moisture forecast by location, this information being transmitted along with a local FM radio signal. This product is not in production yet, but will soon be undergoing trial in the Houston area.

Wednesday, March 5, 2008

The Lifecar

In my February 5th post I mentioned a prototype electric car shown at the Detroit Auto Show and based on the Saturn Vue. Its claim to fame was the use of ultracapacitors to store energy recovered from regenerative braking. (Ultracapacitors take advantage of the high surface area to volume ratio of nanomaterials to store energy more compactly than could be done with a conventional capacitor or battery. Capacitors in general have the advantage over batteries of being able to store and release their energy very quickly, making them ideal for regenerative braking.)

The BBC is now reporting that the same idea appears on a hydrogen fuel-cell powered car which will be shown at the Geneva Motor Show which opens tomorrow. Called the Lifecar, and developed by Oxford and Cranfield Universities together with private industry, it is based upon the Morgan Aero 8 sports car. The Morgan’s already light weight is reduced further by removing luxuries and even air bags. Even then, the performance is not sports-car-like. Indeed it is barely adequate for a family sedan, with a top speed of 90 mph and 0-60 time of 7 seconds. (It is not clear whether this is with the aid of the ultracapacitors or not.) A range of 250 miles is claimed, at which point one would have to find a hydrogen station.

See for full story.

Tuesday, March 4, 2008

Skeptics Conference

[It is now Friday 7th and, although the conference ended on Tuesday, google ads are still appearing for it, for example on this blog. As I say in this posting, they don't seem to be very well organised.]

The International (skeptics) Conference on Climate Change enters its last day today. They seem a bit disorganized, running a 7/8ths-page ad in the NYT only yesterday, the second day of the conference. Speakers include Czech President Vaclav Klaus, and ABC’s resident idiot John Stossel. Vaclav Klaus is not to be confused with his predecessor Vaclav Havel, who has written against climate change for example in a NYT Op-Ed last September ( It is not clear to me why politicians have independent (i.e, not informed by expert opinion) opinions about scientific issues, and in this case I think their opinions are about as useful as Mbeki’s views on HIV.

They claim the conference is sold out, but apparently that is only 500 people. They also say that James Hansen and Al Gore were invited to attend but declined. Even the organizers don’t seem to be saying that climate change is not happening, btw, but rather that it is not a crisis.

The NYT published a story on the conference today. See

For a simple reposte to skeptics on the science see my post yesterday.

Monday, March 3, 2008

Dealing with Skeptics

The New York Times reported on Sunday that climate change skeptics are drawing attention to the recent cold weather in China and other places to cast doubt on climate change. (See I have not written on the science before, because I did not think it was necessary, but maybe this is an excuse to rehearse the argument I use on the increasingly rare occasions when I am faced with a skeptic.

Frequently I find there is a misunderstanding that scientists are somehow struggling to explain observed climate change. Nothing could be further than the truth. Climate change due to human activity -- anthropogenic climate change – was predicted by John Tyndall as early as 1860 (see and has been vigorously promoted by James Hansen of NASA (see for example since the 1970’s. In other words the theory preceded the observed effect.

Because of this, the focus over the past decade or so on whether we are actually observing climate change has been a diversion which has had the effect of wasting a lot of time during which we could have been taking action. Of course, the scientific method requires that we test our theories by observation, but there are different kinds of scientific theories. Testing climate change by observation is not a defining moment for science, like for example demonstrating that light gets bent by gravity validating the general theory of relativity. It is more like watching a heated kettle of water in the expectation that steam will appear from the spout. If it does not, we have some serious rethinking to do, but nobody seriously doubts that it will. Arguing about whether we actually can see the first wisp of steam is not very productive.

In the case of climate change, if it did not happen then we would have to rethink a good deal of the physics we thought we have known for over a century. It is a simple energy imbalance due to the absorption spectra of greenhouse gases and the different spectra of incoming radiation from the sun and the outgoing radiation from the earth. More heat comes in than goes out, so the earth warms up until it reaches a new equilibrium. Except that right now we are adding to the greenhouse gases to this equilibrium temperature keeps rising.

(It is perhaps worth noting here the amount of inertia in the system. Even if we could stop all greenhouse gas emissions today, stablizing the current concentration of these gases at 380 ppm of carbon dioxide equivalent, the average temperature of the earth would still continue to rise for decades. And then of course there is inertia at the next level down, in that we cannot stop the emissions today. The goal of IPCC efforts is to stabilize the concentration at 450 ppm.)

The precise effects of climate change in specific regions are much less certain, and skeptics often seize on this uncertainty. The reason for the uncertainty is that the heat landing on the earth is concentrated towards the equator, whereas the radiation from the earth is more evenly spread. Heat gets transferred from the equator towards the poles by air and sea currents, and predicting how these will be affected by climate change is much more difficult than the simple energy-balance model which tells us that the average temperature of the earth has to increase. Some places may get wetter, others drier, some may even get colder. There are very complex computer models but they probably cannot be relied upon as definitive. What we can be pretty sure of is that there will be disruptive changes.

If all the above fails to convince a skeptic, one can always fall back on the last resort sometimes known as the precautionary principle. If there is even a significant chance of catastrophic effects of anthropogenic climate change is true, does it not make sense to act as if it is true? If we were in a car heading towards what looks like a concrete wall we would not delay braking because it might be a paper mock-up, still less because we could not predict exactly which bones we would break.

As I write this, NPR is running a story about one example of a possible local effect. The locks on the Panama Canal are being widened and deepened to take larger ships. Its operation is however threatened by climate change because it depends upon rainfall. The canal rises 85 feet above sea level and the water for the locks on both sides is gravity-fed fresh water from artificial lakes. Climate change could reduce rainfall and threaten its operation. Of course, by then the Northwest Passage may be a viable alternative.

Saturday, March 1, 2008

My Experience with a Smart Power Strip

[Amended March 2nd. It seems the sensitivity problem with the printer, mentioned towards the end of this post, is still an issue. I will investigate further and report back, probably next Saturday.]

I recently tried out a SmartStrip surge protector from Colman Cable Inc. It is a combined power strip and surge protector intended to save electricity by automatically switching off peripheral equipment when one controlling device is switched off. It seems rugged and well made. The model I bought cost $43.95 from (there is a smaller model for $30.95) and has a total of 10 outlets: one for the control device, 6 for controlled devices, and 3 which are always live (unless you switch the power strip off). It has a lighted switch, a light to indicate whether the controlled devices are on and another to indicate that surge protection is working properly. Finally, there is a screw to control its sensitivity.

So, how useful was this in practice? Firstly one has to find a suitable application, and I had two in mind. One was entertainment. In one room I have a TV, satellite receiver, CD player, DVD player, and a tuner/amp used for the sound for everything except the DVD (because I ran out of amplifier inputs and rarely use DVD). All these devices are on standby. I also added a cordless phone charger to the mix, thinking that I listen to the radio enough to keep the phone charged and in any case there is another phone in the house. One hears a lot about not leaving things on standby and not leaving chargers plugged in when not in use, but I was not sure how much electricity was involved. Using the Cent-a-Meter described last Saturday I was unable to measure any difference very reliably – of course there could be other things going on in the house, and I might try again later with a monitor specific to the outlet – but it would seem that all these 6 devices used about 0.1 kW between them. This might not sound much, but at 16 cents per kWh it adds up to about $120 per year if left on when not needed 20 hours a day, which would pay for the SmartStrip in a few months.

I chose the tuner/amp as the control device, for two reasons: firstly, it mostly needs to be on when anything else is in use; and secondly, if it has been switched off (not on standby) it powers up with tuner on. I also found that I could not switch the satellite receiver completely off because when power returns it goes through lengthy signal acquisition process. So, this needs to be plugged into one of the permanently on outlets and the overall saving may therefore be less than 0.1 kW. Incidentally, I found that two of the devices – the tuner/amp and the satellite seem to use more power on standby than when on. I consistently measured a 0.03 kW difference on each. The TV is the only one which had a significant increase in power usage – about .15 kW – when on rather than on standby.

Now for the other case. In another room, I have a computer, external hard drive, printer, DSL internet connection, and wireless network controller. Between them they use about 0.3 kW when on. (Note that this is a case of equipment which in the past we have tended to leave on rather than just on standby. I have a computer in another room, which gets access to the internet though the network.) The internet and wireless network use transformers, and it seems these are not suitable for the controller. Likewise the computer, partly because it may not be needed when the network is and partly because it is a laptop with a charger so power consumption does not correlate well with whether it is on. So, I chose the printer as the controller. I found it quite hard to adjust the sensitivity to cope with the quite small power usage of the printer, but it now seems to be working and based upon the same assumption as above I project savings of about $350 per year.

I started out thinking the benefits would be minor, but overall savings of $470 per year on a total bill of $3000 is not to be sneezed at. Second only to the pool pump controller discussed in an earlier blog, which I estimate to be saving about $900 per year.