"Perfectly good SI?" How about perfectly improper SI? As a discussion on an IEEE list server, I'm shocked. All electrical units are SI even if electrical engineers sometimes have to deal with a hodgepodge of SI and Customary units. All electrical engineers are perfectly comfortable with using appropriate SI prefixes with those those units. How improper is "billions of kilowatts?" Let me count the ways: *The SI has a perfectly good prefix for the situation and proper SI for "billions of kilowatts" is terawatts (TW). *It is not true that "billion" is correctly understood in all variants of English. US English is clearly 10^9. Traditionally, UK and Commonwealth English has meant 10^12. However, they seem to be adopting the US definition, and I have no idea what a Brit means when he says billion. *If billion is used as a "sort of" prefix to reduce digits in the number, it is a double prefix and improper (plus not being an SI prefix in the first place). Written out as ten or more digits, it is an absurb departure from the "guideline of 1000" (not a rule as there are exceptions) that can't possibly be justified by other numbers in the column. Energy used or generated per year is a power, and the coherent SI unit is the watt (with suitable prefix). Much like vehicle speeds in kilometers per hour, there are some arguments for measuring energy per year in joules per year (with suitable prefix) because it produces more usable results in terms of energy reserves, energy pricing, financial results. There is no rational argument for billions of kilowatts.
--- On Thu, 5/7/09, Stan Jakuba <[email protected]> wrote: From: Stan Jakuba <[email protected]> Subject: [USMA:45031] Re: [SI] Letter to ed To: "U.S. Metric Association" <[email protected]> Cc: "U.S. Metric Association" <[email protected]> Date: Thursday, May 7, 2009, 4:26 PM My dear Bruce: With trepidation, I must point out that among the reasons for the US not being metric yet is that a leading figure in the metrication effort considers "billion kilowatts perfectly good SI". The English speaking word was (is) not my only audience. My audience was (is) the world, world where some countries speak English and English only, some countries speak English as a second language, and some that speak non-English languages only . But they all, no exception, know of W (not necessarily of watt) and, thanks to computers, of G. ASME is ASME International. International does not mean English speaking. SI is international in that other sense. This might lead to understanding why "billion of kilowatts" cannot be SI, let alone perfectly so. All countries have translators and interpreters, who, you might notice, are to be superfluous for SI. Finally, the editors did not miss recognizing GW. The editors, as most editors do, objected to NUMBERS is what I wrote. Furthermore the next sentence was: "It has been my experience with most publications that they resent numbers ("we do not want to confuse our readers" (!)).Stan ----- Original Message ----- From: Bruce Barrow To: Stan Jakuba ; [email protected] Cc: U.S. Metric Association Sent: 09 May 07, Thursday 09:25 Subject: Re: [SI] Letter to ed My dear Stan, You misunderstood my message. I specifically recommended "billions of kilowatts", which is perfectly good SI, and would be clear to editors who don't recognize GW. Yes, I know you have a phobia about billions, as does your favorite SI10 standard, but the English speaking world, which was your audience, knows that a billion is a thousand million. Bruce ----- Original Message ----- From: Stan Jakuba To: Bruce Barrow ; [email protected] Cc: U.S. Metric Association Sent: Wednesday, May 06, 2009 6:55 PM Subject: Re: [SI] Letter to ed Bruce: Using GW has little to do with it being known or unknown. Any number of energy units in use are not known to somebody (many!) and that is one of the reasons why the science/engineering illiterate American politicians cannot agree on the energy issues. Among the dozens of units and symbols for energies one sees, I particularly dislike "millions of tonnes of oil equivalents" and similar contraptions. The GW is not any more confusing than those contraptions including millions of quads per fortnight, or billions of watts, or this beauty (I quote): "..... an average of about 66 megawatt hours in an hour." I observe that more Americans know of W than of hp, let alone Btu/hr (per min, sec, day, ...) or whatever made-up unit. And who knows how much a billion is? There are peoples to whom "billion" means not the US billion even in English, and ASME is "ASME International". You and me are in the business of promoting metric for the good of this country. When then would you suggest we start using SI to reap its full advantage? The I-P peoples, it seems to me, learn units by assimilation of the observed rather than systematically. Thus seeing and hearing SI units and prefixes will sink in (gets learned) just as any other unit did. People do not need to be told it is metric. The GW can be viewed just as the Btu, quad, or tonne of oil equivalents. We have been "selling metric" and failing as you point out. It's time to change course. Sell units, forget about selling metric. How to sell units? Use them. When? Now. Where? Everywhere. Aside from the metrication promotion, I cannot imagine trying to show the renewables analyses results in anything but coherent units. It happens that the only coherent units are SI. Not my fault - I'd have to invent it if it did not exist. Thanks for the comment. Stan ----- Original Message ----- From: Bruce Barrow To: [email protected] Sent: 09 May 06, Wednesday 08:55 Subject: Re: [SI] Letter to ed Stan, I certainly support your discussions on renewable energy. Let me respectfully suggest that the problem with your sales pitch as a sales pitch may be not the numbers, but the GW. Is that symbol known to mechanical engineers? Is the gigawatt understandable to that audience? Would billions of kilowatts have been more easily received? We have a giga-ntic problem in selling metric -- it is tera-bly confusing to the general public, and possibly even to mechanical engineers. :-) Bruce ----- Original Message ----- From: Stan Jakuba To: [email protected] Sent: Tuesday, May 05, 2009 9:49 PM Subject: [SI] Letter to ed The Mechanical Engineering magazine published an excerpt from the letter I had posted here earlier. Unfortunately, the published version, while promoting metric, omitted the metric numbers. Here is the MSWord version of the original. It has been my experience with most publications that they resent numbers ("we do not want to confuse our readers" (!)). Maybe my engineering background makes me think that numbers are more useful than adjectives such as huge, expensive, skyrocketing, ..... that one reads and hear endlessly. But I do agree that numbers in I-P units can indeed be confusing. :-) Stan Jakuba
