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April 3, 2010


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Description of Global Financial Data's oil prices:"Data from 1898 to 1912 are taken from the NBER. Prices are avearge monthly price per barrel at wells, pipeline certificates, January 1890 to January 1895, Pennsylvania Crude at wells, February 1895-1935. Quotations are from Stowell’s Petroleum Reporter (January 1890-September 1901) and from reports by Miss Belle Hill of the United States Geological Survey of 1902. 1903 monthly quotation oil city derricks, and for 1904-1912, first of each month quotation for Oil City Derrick.' Prices from 1898 to 1941 are the price per barrel for oil in Oklahoma City."


spencer: 1) I'm showing motnhly data 1931 to 1939, the BP data is annual data (over a different and longer time period), which would smooth out the highs and lows during the year. 2) The real price of oil according to BP almost doubled from 1931 to 1934, and did approximately double between 1931 and 1937.

Hong Kong Company Formation

Even though an electric car does not have a tailpipe, an electric car produces greenhouse gas emissions where electricity is generated.


Even if electric vehicles today are the equivalent of a 35MPG vehicle for CO2 emissions, that will not be true tomorrow. There is a very good explanation about why we want to go all EV now regardless of the CO2 equivalence today at Electric Vehicles are the Equivalent of a 34mpg Gas Powered Car – Do They Have a Future? Very good points.

Link text: Electric Vehicles are the Equivalent of a 34mpg Gas Powered Car – Do They Have a Future?
URL: http://blogs.windward.net/davidt/2012/04/21/electric-vehicles-are-the-equivalent-of-a-34mpg-gas-powered-car-do-they-have-a-future/


One side of the equation is many times overlooked the mass ratio of the vehicle itself versus the driver,passenger(s) and cargo.
For a single occupant and this is very common a 150 pound driver going from point A to point B is driving a 3000 pound automoble.This is a ratio of 1 to 20.In other words most of the energy used is wasted transporting a heavy vehicle rather than the person going from starting point A to destination B.A tremendous waste of energy in exchange for convenience.This is why I ride a Veltop equipped near all weather electric assisted bicycle instead because it has even a much lower mass for the rider getting from point A to destination B and back.However I'd prefer an electric motorized Velomobile which is even better.
In case one assumes that a bicycle can't carry cargo a Yuba Mundo cargo bike is capable of carrying a 150 pound rider and up to 440 pounds of cargo.I've seen them carrying two full beer kegs,and one carrying dozens of two by four lumber no kidding in addition to carrying multiple passengers.There is even an electric motorized version of the Yuba Mundo cargo bike known as the El Mundo.


Dan,Good points on what the relvaite costs show, but the frontal area of teh car and coefficient of drag have a very large impact at higher (highway) speeds. Weight is more dominant at city speeds with more acceleration.If your marginal electic kWh is coal, the electric probably hasn't saved any green house gasses. With an electric car you are transferring the inneffcient heat engine step to an external location, but it is still there. The coal plant is more efficient (if I recall correctly 40-50% vs 25-40% for a gas engine), but there is more CO2 per fuel BTU than gasoline. The cost savings as Dan pointed out is in the cost difference of the source fuel.In North America the marginal electric BTU is almost always going to be some mix of coal and natural gas, as Hydro is run to produce essentially 100% of the resivour availability, and Nuclear is run flat out, since in both cases the marginal cost once you have built and staffed a plant is nearly 0. For fossil fuel plants the largest cost is fuel (mroe so with natual gas than coal).


No responses yet?I am not going to do any math this week, so I am going to iogrne the actual calculation debate. However, I will comment on the Leaf vs. Corolla consumer decision.From a consumers perspective, I would think that we will need to account for an uncertain depreciation rate for the Leaf. I would guess that the risk of having to fork over excessive amounts of cash in the future to repair your Leaf needs to be factored in, whereas with the Corolla there is a repair track record and lots of friends with Corollas you can get repair info from. I am not saying that it would actually have a higher depreciation rate (i.e., higher risk of expensive repairs), just that it has zero repair track record and risk averse consumers would put some value on depreciation rate information. On the other hand, some consumers may get a non-monetary benefit from either the appearance that they are eco-friendly (e.g., the South Park Prius Effect!) or tech savvy (i.e. an early adopter). But these things would probably be much more difficult to measure.Anyways, those are just my two cents.Joel


Hi Ray,First off, you are correct, in that you will need one big solar panel set up . The gerneal recommendation for solar panels for fence chargers: is that you will need approximately 10 watts of solar panel for each output joule. In your case, with 15 stored joules, you probably have about 10.5 output joules. 10.5 x 10 = 105 watts of solar panel. Plus you will probably need multiple storage batteries.Rather than me make some broad recommendations for you I would prefer to put you in touch with an expert and someone who can compute this for you better than I.Contact: Steve Core, Fence/Scale Repair Tech at Zeitlow Distributing Co, in McPherson Kansas. His email is: or call him directly at: 800.527.5487 or 800.364.1605I refer to Steve often for technical questions he has been working on fence chargers since Noah unloaded the boat .He can answer your questions and even build or supply the system for you if you choose to do so.I hope this helps. Additionally, unless you need this much power on this one fence, you might also consider splitting the system and running it off of two smaller seperate systems rather than one large one. Just a thought.Let me know where you are located and please re-comment on what you find our from Steve,Thanks, Gary

642-243 dump

I'm using figures based on meta studies of numerous lifecycle analyses across different countries. Yes, these figures will vary across refineries and countries, but the variation isn't too large. I can't see the point in using kWh metrics when a whole literature of lifecycle analysis is available. So many of the energy inputs are non-electric

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