Wednesday, August 27, 2008

Thank Growth Green Machine

Green Machine

Thank Growth It’s Wednesday

Today’s article is brought to you in a sarcastic fashion courtesy of the unimpeded growth the world has experienced in the past several decades. Of course economic growth is good but population growth, energy growth, urbanization, and correspondingly growth in the concentration of greenhouse gases in our atmosphere has also resulted. I did some research on the internet and found a very interesting article issued by the Metropolitan Transport Commission of our State Government regarding Auto Ownership in the San Francisco Bay Area: 1930 – 2010. The article can be found by going to the following web site

Starting with Marin County where we live, the following statistics hold for the growth our county has experienced. In 1930 there were 11,200 registered automobiles or 1.06 per household or 0.26 per person living in the county. By 2010 we anticipate there will be 241,300 automobiles in Marin County or 2.16 per household or 0.89 per person. Wow we have come a long way since 1930 or have we? The statistics for San Francisco County show less growth in the past 80 years. In 1930 in the city by the bay there 152,700 registered automobiles or 0.85 per household or 0.24 per person living in San Francisco. In 2010 it is estimated that there will be 445,000 registered automobiles or 1.3 per household or 0.54 per person living in San Francisco. Interestingly back in 1930 Marin and San Francisco had a similar number of automobiles per inhabitant, but by 2010 we Hot Tub Enthusiasts have almost as many vehicles as people. It can be inferred that the carbon footprints of those living in the fog are lower than us because of the compactness of their city and the availability of public transport.

Before all of us go cry tears to fill our hot tubs, Sonoma County to our north experienced similar growth. Back in 1930 there were 26,500 registered automobiles or 1.46 per household and 0.43 per person living in Sonoma County. By 2010 we anticipate there will be 455,000 in Sonoma County or 2.18 per household and 0.84 per person. In 2010 there will be more automobiles registered in Sonoma County than in San Francisco County. Now we know why Highway 101 through Marin is choked. Other counties in the bay area such as Santa Clara, Contra Costa, San Mateo, Alameda, Solano, and Napa have all experienced massive growth in vehicles and population in the past 80 years. The following are the frightening statistics for the entire Bay Area. In 1930 there were 461,800 registered automobiles or 1.04 per household and 0.29 per person. It is expected that in 2010 there will be 5,577,300 registered automobiles or 2.03 per household and 0.75 per person. That is three cars for every four people. It is frightening that Sonoma County today has as many registered vehicles as the entire Bay Area had in 1930. While Marin has somewhat limited population growth over the past 80 years we hot tubers have the highest number of vehicles per person at 89 per 100, a statistic that should scare us into immediate action

Wednesday, August 20, 2008

Thank Gas

Thank Gas It’s Wednesday

Today’s article is brought to you courtesy of that state of nature referred to as the gaseous state. Gases have interested scientists for many thousands of years and it took more than three thousand years to develop the kinetic theory of gases. Heron a Greek who lived in the first century invented a steam engine, long before a couple of Brits named Savery and Watt harnessed the power of steam and are wrongly remembered as the inventors of the steam engine.

Three are all sorts of laws covering the physical behaviour of gases. These include Graham, Boyle, Charles, and even a French scientist and politician named Gay-Lussac. My favorite is the Ideal Gas Law. A gas is ideal if its pressure increases in perfect proportion to the absolute temperature. If the increase in pressure is not in perfect proportion to the absolute temperature then the gas behaves imperfectly and has a fugacity coefficient that is not unity. It seems like political candidates of the male species repeatedly behave imperfectly and hence have the audacity to deny to the popular press that they did not exhibit some fugacity. Of course French politicians are allowed to openly display an enormous amount of fugacity.

CNN is now carrying news of a Compressed Air Car that will propel the world with little fuel. Actually, I hosted the California promoter of this contraption at my home in Tiburon about five years ago. I took a quick look at the proposed vehicles and told the promoter it simply would not win any major share of the vehicle market. The inventor of the Air Car is a Frenchman named Guy Negre who wants to be the next Gay-Lussac and have a gas law named after him. Negre has further developed his compressed air car to now use fuel to increase the range and speed of his car. Actually he now has a car that is gasoline or diesel car that is augmented by compressed air, sounds like a turbocharger to me so why compress air into a scuba tank and waste the wonderful form of energy called electricity in what turns out to be an inefficient, bulky and Rube Goldberg like contraption.

If one already has electricity, it is a lot more efficient and simple to store this electricity in batteries on board a vehicle. Now the inventor of the pure air car realises he has to obey the gas laws, he has abandoned the pure air car for the hot air car. Just today CNN online aired the story of 106 miles per gallon for a six seater air car. Yes it is 106 miles per gallon without including the electricity used in compressing the air and therefore the fuel that was used to generate the electricity. Perhaps the 106 miles per gallon was also achieved travelling down hill so that the added mass of the scuba tanks and compressed air contributed to gravity’s pull on the contraption. One can store about 100 watt hours of energy in a kilogram of compressed air at 200 atmospheres pressure. By comparison a 3 fluid ounce double shot glass full of diesel has 1,000 watt hours of stored chemical energy or about ten times as much. Also for its storage diesel does not need a scuba tank that is also much heavier than a diesel tank. Please do not use your double shot glasses to drink diesel even though it is truly fire water.

Wednesday, August 13, 2008

Thank Gears

TGIW - Thank Gears It’s Wednesday

Today we will learn about gears and how they play a vital role in improving the energy efficiency of vehicles. Not many of us can remember stick shifts that were on the steering column. Most vehicles in the 1940s had three forward gears and a reverse gear. The gear change lever was on the steering column. First gear is called the low gear because it has the lowest gearing ration between the engine and the drive wheel or wheels. The low gearing ratio is needed to commence the acceleration of the vehicle and allow the engine to enjoy the greatest “mechanical advantage”. Mechanical advantage is also used in pulleys and cranes to lift heavy items with the least amount of force. Likewise in a vehicle a low gearing ratio is used to allow the horsepower and torque of the engine to commence the acceleration of the vehicle. As the vehicle gains velocity the gearing ratio can be increased and the engine speed can be lowered to continue to propel the vehicle at a certain speed.

If you watch bicyclists who are climbing a hill, they pedal pretty fast and the bicycle is hardly moving. This is because they have engaged their lowest gear ratio between the sprocket on their pedals and the sprocket on the rear wheel. When the bike is on the flat or downhill the pedals do not have to be turned rapidly for the bicycle to move fast, this is because the chain now engages the smallest sprocket on the rear wheel and the largest sprocket on the pedals and allows one revolution of the pedals to drive multiple revolutions of the rear wheel. The cyclist would not be able to climb a hill while engaged in this high gearing ratio as the mechanical advantage has in fact become mechanical disadvantage and the cyclist is simply not powerful enough to exert sufficie nt force to climb a hill.

A human riding a bicycle has the power of about 50 watts or about one fifteenth of a horse. A Porche has over 300 horsepower so it needs many more forward gears than a 1940s vintage car. During the sixties it was common to have “four on the floor” meaning cars got four speed forward gearboxes and the gear shift lever was moved from the steering column to between the drivers seats. This is also because the front seats changed from being bench seats to two bucket seat. During the seventies and through the end of the last millennium five speed gearboxes were the most common for manual shift vehicles. Now six speed manual gearboxes are common on Porches and other high performance cars.

Automatic gearboxes were widely adopted in the 1960s. They were two speed gearing at first and then for many years were three speed. In the 1990s four and five speed automatic transmissions became available and in this decade more six and seven speed automatic transmissions have been engineered. This allows for a much higher final gearing ratio as well as a much smoother transition through the gears which in turn allows the vehicle to achieve much improved fuel efficiency. Nissan has developed a continuously or infinitely variable (CVT) transmission that does not have a discrete number of gearing ratios but rather has a system that allows the gearing ration to change in minute increments and hence is the ultimate in the smooth transition from low gear to high gear. We can thank gears for the smooth ride of modern vehicles and also for the improvement in fuel efficiency and more rapid acceleration. Nissan claims a 10% improvement in fuel efficiency for a vehicle equipped with CVT over a 4 speed transmission. Only a few of us will thankfully have the experience of “three on the column” where cars shuddered while accelerating and engines whined to gain moderate speed.

Wednesday, August 6, 2008

Thank Gore It's Wednesday

Thank Gore It’s Wednesday

Yes our old friend has raised his head out of the alfalfa patch and has provided his green vision of the energy policy that our next president and congress should adopt. Is it realistic to think we can replace all of our electric power generation with renewable energy within a decade? The department of energy reported that the US used 4.065 billion megawatt hours of electricity in 2006. The peak installed capacity is approximately 906,155 megawatts. Dividing the 4.065 billion megawatt hours by 8760 hours in a year the average load is some 464,041 megawatts or some 48.2% of peak power.

The following are the fractions of the electricity generated in 2006 by the various sources of fuel: Coal 49.0%; Petroleum 1.6%; Nuclear 19.4%; Natural Gas 20.0%; Other Gases 0.7%; Hydroelectric 7.0%; and Other Renewable 2.4%. Hence 73% of all electric power generated in 2006 had associated carbon emissions as the fuel contained carbon. Coal and nuclear are baseload plants which means they run all the time. Replacing coal fired power generation station with renewable sources such as wind or solar cannot be done simply by replacing one megawatt of coal capacity with one megawatt of wind capacity, as the wind is intermittent and is at best available one quarter of the hours in every year. Therefore we will have to have massive energy storage capability to remove the=2 0baseload coal fired plants.

Assuming we can install wind turbines for a cost of $2,000,000 per megawatt, if one does all the tedious mathematics to replace the 73 % of the US generation capacity that is carbon based with wind power would cost. $1.32 trillion. However we would need twice as much wind generation facilities to replace baseload carbon fired plants and the cost of the wind generators will equal $2.64 trillion. To store the wind energy so it can be dispatched when it is needed will cost a similar amount, so we are talking about an investment of $5.28 trillion before we add in the cost of the transmission lines that are needed. Let’s assume the transmission system together with the controls needed for dispatching all this wind generated energy cost $0.72 trillion we have a cool $6 trillion needed to be spent over the next decade. This would be significantly higher if PV cells were used instead of wind turbines. Therefore using a mix of wind and PV as well as tidal, r un of the river, solar thermal, and geothermal we may need to invest $10 trillion for the carbon free electric generation replacement system.

We import a total of 12 million barrels a day of crude oil and refined petroleum that costs us $130 per barrel or approximately $570 billion per year. Assuming the world has a savings rate and banking system to allow the US to divert $10 trillion of investment into the alternate electric energy sector, this investment without interest or profit equals 17.5 years of oil imports at present rates and present prices. As I am neither a magician nor the chief economic advisor of the next president, I cannot forecast the price of oil or the level of imports over the next two decades. However, I do believe that the level of imports will drop and the price of oil is presently unaffordable and possibly unsustainable. This being said it will take 20 years or more to recoup the dollars we ship overseas for oil for the total replacement of carbon based electric power generation.

It is not completely infeasible that the system could be replaced, but it will simply place a major economic burden and will also substantially increase the cost of electricity to the consumer. My vote goes to the proposition to replace one quarter of the carbon fired power generation with renewables, as well as reducing our electricity consumption by a total of 10% in ten years time through demand side management and deployment of more efficient technologies. We certainly should spend a couple of trillion dollars over the next decade on alternative energy. This amount matches the total of the lowered home values and subprime mortgages losses we are experiencing and it is not going to divert all of global savings and investment to renewable energy but will leave some money for, social security, schools, hospitals, high-tech, biotech and of course old Al who makes millions on his speaking engagements that he flies to in his private jet.