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Old 02-09-2016, 02:48 PM
David Dewey David Dewey is offline
 
Join Date: Jul 2006
Location: Northern California above Lake Oroville on "Dewey Mountain"
Posts: 1,153
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As Dale pointed out, my statement that steam can be generated more cleanly than diesel engines was only part of the story. Because steam is raised by external combustion, a variety of fuels can be chosen to do so, and burners can be designed to optimize that combustion, leading to lower pollutants. One of the causes of troublesome emissions in an internal combustion engine is the high temperatures & pressures create other substances. However; raising the steam is just providing the means of power; one then has to use it, and this creates all sorts of other problems. In the old days there were folks around who could deal with these issues. Nowadays, those folks are rare, and becoming rarer. All of this costs more money than operating what is now considered a "normal" means of propulsion. As time moves farther and farther away from the steam propulsion era, such talent becomes even more rarefied.

Also, one reason the boilers in the Delta Queen have served her these many decades is that they were over-designed for the demands of the Delta Queen. This happened because, during the DQ's & DKs's construction, they were available much cheaper than a custom-built boiler. I don't know what actual shape the boilers are in now, but you can bet that there is wastage of the pressure vessel's metal; it's the nature of boilers. Sometimes this can be replaced, and sometimes it is less expensive to just replace the entire pressure vessel. Some have said that new boilers are part of the plans (this is given that she will remain steam-powered); what dismays me is that the new steam plant will likely be designed to just meet the current DQ steam requirements, not exceed them like the current boilers did. This means, by the very nature of modern engineering, they won't last nearly as long. I worry about "modern engineering" where everything is built to the most economical standards known, and often to a planned obsolescence. For an example, a daily-life thing we can all relate to; We are encouraged to change out our florescent light fixture ballasts for modern, more energy-efficient ones. So we take out the old ballast, likely it's more than 15 years old, and put in the smaller, newer "efficient" ones. I've done this in commercial installations. I found the new ones usually failing shortly after their 5-year warranty expires. I asked a power company engineer about this, "off the record." His response was, "Yes, the new units do not have the life-span of the old ones; it's part of the cost of the efficiency." Hmm, I don't think they figured out the cost (both to the consumer and of the raw materials and manufacturing costs) of the multiple replacements over time compared to the old!
But, this is a different soapbox I'm standing on! The one I started standing on was just one clarifying my statement that while steam can be generated more eco-friendly than an internal-combustion engine, I needed to add that steam generation is only part of the equation, the operating costs go up when you convert the steam into motion, both in machinery and in personnel. Life is never simple, is it?
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