Tuesday, July 22, 2008

Thank Gravity It's Wednesday

Yes gravity is a gift of nature when it comes to renewable energy. Hydroelectric and tidal power are the result of the pull of gravity on bodies of water. The Hoover Dam also known as the Boulder Dam is an engineering marvel and is capable of generating 2,080 megawatts of electric power thanks to the depth of the turbines below the surface of the dam. It is actually Lake Mead that is the lake behind the dam that provides the electric power thanks to the pull of gravity on the water inside the lake. Construction of the Hoover dam was completed in 1935 and at that time it was the largest hydroelectric facility in the world. Presently, the Hoover Dam is only the 34th largest hydroelectric generation station in the world. http://en.wikipedia.org/wiki/Hoover_Dam

In order to produce one megawatt hour of power approximately one million gallons of water have to flow through a turbine if the water has approximately three hundred feet of water above it. The Hoover Dam is 726 feet tall so for this dam to produce 2080 megawatts approximately 860 million gallons of water have to flow each hour if the dam is full. As the dam is not full due to the drought, the turbines are not capable of producing their full nameplate capacity of electric power.

The Hoover Dam is a awesome structure but it really only provides a minute fraction of the power consumed in the USA. Also if we were all to buy Tesla Electric Motor Cars we could not charge too many of these cars simultaneously. The Tesla Roadster has a battery storage capacity of 54 kilowatt hours and charges in 3 hours. This means the Tesla draws 18 kilowatts of power. With a capacity of 2080 megawatts or 2,080,000 kilowatts the Hoover Dam could simultaneously charge 115,555 Tesla Roadsters. The charging is accomplished in 3 hours and the Tesla is good to go for 4 days if you drive 50 miles a day. Performing the requisite math in the 4 days you could charge 32 times 115,555 vehicles or 3.698 million cars provided it takes no time to hook-up the next series of vehicles to their chargers. Unfortunately, this is fewer vehicles than we have in the Bay Area, therefore the entire output of the Hoover Dam would not be sufficient to power all the vehicles on the road in the Bay Area even if they were Tesla Roadsters with state of the art batteries and power control systems. http://www.teslamotors.com/

One cannot fault gravity for the limit of how many vehicles the Hoover Dam can power. Rather we should fault ourselves for driving vehicles that weigh 15 times what we weigh and that we drive all over the place to work, shop, or enjoy some entertainment. Even if we moved to Jupiter, a planet that experiences 2.54 times the gravity on earth, we would still not be able to propel many more vehicles from the power generated by a Lake Mead on the surface of Jupiter. Yes we would generate 5,283 MW from the same lake on Jupiter but alas our cars and our bodies would also be 2,54 times as heavy. The power required to propel a car does have some relationship to the mass but is mostly related to the energy required to overcome air (atmospheric) resistance. No one has been able to measure the atmospheric pressure of Jupiter so I cannot tell you the range a Tesla Roadster would have on that planet. I can tell you it would be better to go to Mars with our Tesla Roadster and our Lake Mead. The atmospheric pressure on Mars is only 1% that of earth so atmospheric resistance will be negligible. Gravity on Mars is 38% that of gravity on earth. Our Lake Mead would only generate 790 megawatts but we would all weigh 62% less on Mars. Hummers would be fuel efficient on Mars due to the low gravity and very low atmospheric resistance. I will call the CEO of GM tomorrow and advise him where he can sell all of his spare Hummers. As for his spare Saturns I have no idea what he can do with those. http://coolcosmos.ipac.caltech.edu/cosmic_kids/AskKids/mars_gravity.shtml

Wednesday, July 16, 2008

Thank Garbage

TGIW – Thank Garbage It’s Wednesday

Today we thank the trash we throw out for its energy content and value. The USA is the world’s greatest waster of materials. Over 251 million tons a year of municipal solid waste was generated in these United States in 2006. We consume and discard vast amounts of paper, food, plastic, cans, bottles, and other consumer goods. I had this thought what if we could turn this waste into energy or other useful material. Well I have to admit others have beaten me in the race to recycle.

The cities of San Francisco and Oakland are now recycling food scraps from restaurants and making composted material for fertilizing the vineyards in Napa and Sonoma. Yes some 300 tons a day of organic material that can be composted is hauled to a Vacaville where a facility run by Jepson Prairie Organics turns this waste into useful fertilizer. Composting is an aerobic process, meaning air is added to the pile of waste to help decompose the material. http://www.jepsonprairieorganics.com/ What is not reported is that the gas emitted from a compost heap is carbon dioxide. However had the waste been placed in a landfill it would be more likely that an anaerobic (without air) breakdown of the trash would emit methane gas. Pound for pound methane gas has over twenty times the greenhouse effect of carbon dioxide.

Another way to reuse the food scraps is what the Mount nelson Hotel in Capetown South Africa is doing. This stately hotel with five acres of gardens is feeding food scraps to its worm farms. These worms breakdown the food scraps into a liquid fertilizer as well as a nutrient rich mulch. Also the worms grow at a prolific rate and are a source of protein for birds and poultry. http://biophile.co.za/recycling/worms-at-the-mount-nelson

It is amazing to me that we here in the USA have a recycle rate for aluminum cans that is less than half. If you consider that the amount of energy needed to fabricate an aluminum can will power a 32” LCD TV for three hours, this is perhaps the most wasteful item in our trash. The good news on the recycling front is that we recycle over 99.0% of the lead acid batteries we have for our vehicles and data centers. The following recycle rates have been reported by the US EPA for various materials for the year 2006: Steel Cans 62.9%; Yard Trimmings 62%; Paper and Cardboard 51.6%; Aluminum Cans 45.1%; 34.9%; Plastic Milk Bottles 31.0%; Plastic Water Bottle 30.9% and Glass Containers 25.3%. http://www.epa.gov/garbage/facts.htm

One may ask why do recycle more steel cans than aluminum cans even though aluminum is more valuable pound for pound? My educated answer is that steel is magnetic and it is much easier to extract steel from a pile or garbage by simply running the garbage over a magnetic separator. The recycle rates for aluminum cans and plastic bottles are higher in states that have enforced a deposit law and hence placed a greater value of the container. Many states do not have deposit laws or cash redemption values for beverage containers. The California Refund Value (CRV) is 5 cents for containers less than 24 ounces and 10 cents for containers greater than 24 ounces. The Golden State has a combined recycle rate for all aluminum, plastic, glass, and steel beverage containers of over 70% (14.7 billion out of 21.9 billion in 2007). This proves one man’s trash is another’s treasure.

Thursday, July 10, 2008

Thank Galaxies

TGIT - Thank Galaxies It's Thursday

I was watching a TV show about the universe on the History Channel. Scientists have, since the time of Newton, used mathematics to model the physical world. Much of the modeling has been to describe motion and gravity. Einstein developed the notion of Space-time surfaces that warp in the presence mass. Einstein did not subscribe to the notion of an expanding universe even though his math supported this phenomenon. In order for the big bang theory to hold, there has to be this initial state where all the four fundamental forces (gravity, electromagnetism, strong nuclear forces, and weak nuclear forces) were all combined in a single force. When the big bang occurred the gravitational force was the first to split and break away from the other three forces. Soon thereafter the three other forces also split apart. An observation that led to the unified force theory and the initial inflation after the big bang is that most of the outer universe has the same temperature. This can only be explained in that the initial inflation (Guth's theory) occurred at a speed faster than the speed of light. This is very scary stuff and makes my head spin. http://www.pbs.org/wnet/hawking/mysteries/html/guth_1.html

All this physics is fine, but we still have the basic inflation problem of high energy prices on planet earth billions of years after the big bang. Physicists and chemists are trying to develop nano-systems to store more electrical energy so we can use less gasoline and deploy plug in hybrids. This company in Texas (EEstor) claims to have an ultra-capacitor that can store enough electricity to allow an automobile to travel 500 miles. All of this energy is claimed to be placed into the ultra capacitor in five minutes. The rate the electricity is transferred exceeds 1 Mega Watt, so don't rush to buy one of these gizmos as you will need 10,000 amp service in your home at 110 volts. The typical home has 100 to 200 amps of service. If the ultra capacitor short circuits we could reenact the Big Bang right here in planet earth. http://en.wikipedia.org/wiki/EEStor

A much more likely technology for hybrids and plug in hybrids will be lithium batteries that recharge in three to four hours and let you travel a distance of approximately 100 miles. The recharge rate will be limited by the electrical service that PG&E has connected to your home. I am now doing an hour long radio show on Wednesdays at noon on blog talk radio. Last week I opined on the technical possibilities of the lithium batteries and how they may be the winner of the $300 million prize John McCain has proposed to leapfrog current automotive technology to gain increased fuel efficiency. The show can be heard either by calling on the phone at 347 838 8999 or using your computer to go to http://www.blogtalkradio.com/AlternativeEnergyCom

One final word, our neighboring town of Mill Valley, California recently hired a sustainability consultant to guide the city on green policy. The consultant will be paid $30,000 a year. I say Tiburon – Belvedere where I live should leapfrog Mill Valley and let me consult to our town councils and make 94920 the greenest Zip Code in the nation. Maybe I could even run for mayor and my campaign slogan will be “Be Green Vote Leveen”.

Wednesday, July 2, 2008

TGIW - Thank Glucose It's Wednesday About a year ago there was news in the electronics press that Sony had developed a sugar powered battery using bio-cells and enzymes that digest sugar. The Sony sugar battery develops 50 milliwatts of power. This is a very small amount of power so don't get too excited that this will be the green technology of the future. By comparison your house uses about one and a half kilowatts of electricity. This means that if you get hooked on the sweet taste of the Sony sugar battery so you will need 30,000 of these batteries to power your home. The battery kind of looks like a fuzzy dice I had hanging on my rearview mirror back when disco was king, GM was solvent, and gasoline cost less than a buck a gallon. http://www.sony.net/SonyInfo/News/Press/200708/07-074E/index.html

All this sweet talk got me thinking about sugar and how much energy this wonderful chemical contains. First one has to understand that sugar is a carbohydrate and that means it has carbon, hydrogen, and oxygen in its chemical structure (carbo for carbon and hydrate for hydrogen and oxygen). Gasoline is simply a hydrocarbon meaning it only has carbon and hydrogen atoms. Sugar has the chemical formula of C12H22O11. Remembering our chemistry this means sugar has 12 carbon atoms, 22 hydrogen atoms and 11 oxygen atoms. Gasoline by comparison is typically composed of 8 carbon atoms and 16 hydrogen atoms. As the sugar molecule is already partially oxidized by having 11 oxygen atoms, thermodynamics tells us that sugar will have a lower heating (fuel) value per pound than a non-oxidized molecule like gasoline. The insurance industry considers sugar as a combustible material because it is only partially oxidized and can therefore fuel a fire. Combusting a pound of sugar yields 7,100 BTUs or enough energy to heat your seventeen gallons of bathwater to a cozy 105 degrees Fahrenheit. Combusting a pound of gasoline would yield about 18,000 BTUs. Therefore, hypothetically speaking, if you could use sugar to fuel your vehicle you would have to carry two and a half times the mass of fuel to travel the same distance.

Next time you do some baking make sure to add six ounces of gasoline as a substitute for a pound of sugar. Only joking you will blow up half of the world if you do this! Don’t ask me how much Splenda is the equivalent BTUs of sugar as I only bake with sugar. I had always thought that sugar cane contained a greater amount of sugarthan do sugar beets. This is not so. Oregon State University reports that beets have 16% sugar versus 14% for cane. Cane sugar is grown in tropical climates allowing the plant to grow faster than beets that grow in colder climates. This is the reason that most of the sugar we eat is primarily produced from cane and not beets. This is like getting "beaten by a cane" which is standard punishment in Singapore for chewing gum even if the gum is sugarless. http://oregonstate.edu/instruct/css/330/seven/index.htm

There is a sugar association in the USA, who claims that sugar is a brain food, that it stops mold from growing, and that it heals wounds. Now we know how Neosporin is made, it is simply a mixture of sugarand petroleum jelly. Given that both of these ingredients are combustible, Neosporin should likewise be a combustible material, however I have not tried that experiment yet. This experiment was in part attempted in Adam Sandler’s latest movie Don’t Mess With Zohan. The results of the experiment in the movie at least indicate Neosporin will not self detonate, so don’t be afraid to use it on a minor cut or burn. http://www.sugar.org/