John, We haven't abandoned BTU's (/hr) - pop into any DIY store and you'll see them mingling with the aircons and central heating systems.
In B&Q they show you how to calculate the number of BTU/h that you need etc. Date: Mon, 30 Mar 2009 18:20:35 -0700 From: [email protected] Subject: [USMA:44245] Re: Wood energy units To: [email protected] Yes, the variability of the calorie is why it is deprecated (for 61 years); well, also because it is not coherent. The BTU obviously has exactly the same problems; if any organization were in charge of Customary/Imperial units, it would be deprecated too. EIA uses the BTU-IT. (Since the British have abandoned the BTU, perhaps it should be renamed the ATU) Using one unit for all thermal energy, even if it is the wrong unit, is far superior to barrels of oil, tons of coal, cubic feet of gas, etc. If the BTU were deprecated, and they insisted on remaining with Customary units, they'd have to use foot-pounds for thermal energy. I don't even want to bother. Let them keep BTU for the moment as dual, but teach them to use the joule properly. Then we can start the rant about the variability of the BTU. By the way, the differences in BTU values undoubtedly pale compared to the uncertainties in the energy estimates. Those are not collected with any great precision by EIA. But the EIA figures are the best available (for the US) and anybody talking about energy is going to set the stage with a comparison to EIA totals or sector totals. Since the EIA has told us to pound sand on joules, that means BTUs. --- On Mon, 3/30/09, Pat Naughtin <[email protected]> wrote: From: Pat Naughtin <[email protected]> Subject: [USMA:44243] Re: Wood energy units To: "U.S. Metric Association" <[email protected]> Date: Monday, March 30, 2009, 3:26 PM Dear John, The BTU and the calorie share a common problem in that they both vary with temperature. A calorie at 20 °C is not the same as a calorie at 37 °C. And the same is true for any of the BTUs. The differences are not great but when you multiply these small differences to discuss issues like the energy consumption of the whole of the USA these small differences become significant. You might be interested in an article that I wrote on this issue during the 2008 election campaign in the USA. The article covers a number of science issues including energy. Although it was written with the USA firmly in mind, I also think that this also places energy units in a broader international context. You can find this at: http://www.metricationmatters.com/docs/AMetricationElephant.pdf I also wrote to Professor Richter as follows: Dear Professor Daniel D. Richter, I understand from a friend in the USA that you are still using the units quads and British Thermal units in your article in 'Science' magazine (2009-03-09). You might be interested in this short letter that I wrote to the Barack Obama Energy and Environment Policy Team. I think that this places energy units in an international and historical context. See: http://www.metricationmatters.com/docs/ObamaEnergyPower.pdf Cheers, Pat Naughtin On 2009/03/31, at 12:04 AM, John M. Steele wrote: Yes, he should use the joule and its multiples. US energy consumption would be about 106 EJ, using his figure. I am torn on whether or not he should drop the BTU figure. In the long run, he shoud. However, in the short term, with DoE, EIA, and the entire US fossil fuel industry using the BTU, should he drop it and make his figures uncomparable, or retain it in parentheses? We may need to get everybody using the joule as primary before we advocate dropping the BTU entirely. The real issue is using the calorie or kilocalorie. It has been deprecated in favor of the joule as the unit for thermal energy since 1948. Isn't 61 years obsolete enough? I hope this isn't how he teaches students to use units. I'm also not sure what he is saying about 10.6 EJ of wood energy in the US. Assuming this Wikipedia article correctly quotes the EIA, 2006 worldwide energy usage was about 471 EJ, of which 4 EJ was the total in the combined category, "geothermal, wind, solar, wood." http://en.wikipedia.org/wiki/World_energy_resources_and_consumption The other issue is that Science magazine may set the units policy for articles. However, I searched their site for author guidelines (which were limited) and could not find any metric policy or units policy. --- On Sun, 3/29/09, Robert H. Bushnell <[email protected]> wrote: From: Robert H. Bushnell <[email protected]> Subject: [USMA:44216] Wood energy units To: "U.S. Metric Association" <[email protected]> Cc: [email protected] Date: Sunday, March 29, 2009, 10:21 PM 2009 March 29 Dear Professor Richter, In Science 2009 March 13 p 1433 you write about Wood Energy in America and list energy as follows: "total U.S. energy consumption, currently about 100 quads [100 x 10^15 British thermal units (BTUs) or 25.2 x 10^15 kcal] per year." The text goes on to use quads (see "10 quads per year"). I suggest that it is time for Duke University to stop using old units and use only joule and its multiples. The article does a good job of making the case for wood. I hope that on units you can do better from now on. Robert H. Bushnell. PhD PE U S Metric Association Cheers, Pat Naughtin PO Box 305 Belmont 3216, Geelong, Australia Phone: 61 3 5241 2008 Metric system consultant, writer, and speaker, Pat Naughtin, has helped thousands of people and hundreds of companies upgrade to the modern metric system smoothly, quickly, and so economically that they now save thousands each year when buying, processing, or selling for their businesses. Pat provides services and resources for many different trades, crafts, and professions for commercial, industrial and government metrication leaders in Asia, Europe, and in the USA. Pat's clients include the Australian Government, Google, NASA, NIST, and the metric associations of Canada, the UK, and the USA. See http://www.metricationmatters.com for more metrication information, contact Pat at [email protected] or to get the free 'Metrication matters' newsletter go to: http://www.metricationmatters.com/newsletter to subscribe. _________________________________________________________________ View your Twitter and Flickr updates from one place – Learn more! http://clk.atdmt.com/UKM/go/137984870/direct/01/
