Energy used per year, which is the basis of the EIA Annual Energy Review, is energy/time, and therefore power. Energy reserves (coal, oil, etc) can be meaningfully expressed in energy units rather than the customary mass and volume units. When divided by the annual (average) power demand, we can determine how long they will last (although history shows we have always discovered new reserves over time.) Usage of energy however is invariably measured over time, and the act of doing so makes it power. Formally dE(t)/dt = P(t).
--- On Fri, 5/8/09, Pat Naughtin <[email protected]> wrote: From: Pat Naughtin <[email protected]> Subject: [USMA:45038] Re: [SI] Letter to ed To: "U.S. Metric Association" <[email protected]> Cc: "U.S. Metric Association" <[email protected]> Date: Friday, May 8, 2009, 9:34 PM On 2009/05/07, at 8:55 AM, Stan Jakuba wrote: 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. … Dear Stan, One problem with this approach is that GW is not an energy unit at all — it is a power unit. Perhaps 'one of the reasons why the science/engineering illiterate American politicians cannot agree on the energy issues' is that scientists and engineers do not make the distinction between energy and power clear at all when they use these two distinct physical realities and their respective units, joule and watt, as if they are interchangeable. After all, energy and power are as dissimilar as distance and velocity. 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.
