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New Zealand Engineering 1998 March

NZ engineering Editorial   Golly, it was hot! <HR>Peter King Managing Editor Winners <IMG SRC="../gifs/king.JPG" NOSAVE BORDER=0 HEIGHT=174 WIDTH=122 ALIGN=RIGHT>In December 1997 I announced we would be offering prizes this year for the best articles contributed to New Zealand Engineering. Winning articles must demonstrate that very tricky combination of readability and relevance to the intelligent lay person plus philosophical insight of the practising engineer.In March we had two winners: Richard Sharpe for his wake-up call for domestic earthquake resistant design and Tuoc Trinh for his article on food product design. Each received $250. While politicians and the media inquisition machine are running about Auckland looking for suitable Mercury Energy sacrifices to burn at the stake the inquiry into why the four 110 kV cables died continues. Early theories focused on the thermal effect of the cables in dried out soil, Mercury has raised the possibility of manufacturers flaws while the manufacturers hint at the effect of gravity on wire down Grafton hill. At the height of the heatwave soil temperatures in Auckland one metre under (just 50 cm above the cable depth) were hitting 21 degrees celsius according to National Institute of Water and Atmospheric Research scientist Jim Salinger. Mr Salinger says ground water was also well down due to the absence of any significant rain since December. Some experts say the operating temperature ranges of the older gas filled cables is between 50 and 90 degrees Celsius. That doesn't seem to leave an awful lot of room for the increasing heat generated by the draw for office air conditioning cranked up to reflect the record temperatures. If the unprecedented heat and dry conditions of the summer of `98 did "cook" the cables or at least soften them up for the gravity effect, then further consideration should be given to the possibility that this problem may not go away. No responsible scientist will dare suggest at this stage - but the possibility exists - that the failure of the cables of Mercury may be the first tangible sign of failing to factor the climate change into operational assumptions. While the tendency is to imagine that a one percent increase in global temperature will manifest itself uniformly across the globe this is not what any models predict. Localised impacts will be more varied. Historical ranges will be skewed and useless for operational modelling. Of course, two consecutive "El Nino" years does not a climate change make. On the other hand those cables had been operated using the same loading calculations perfectly well for over forty years. Some externality, whether it was age, temperature, gravity or all three was clearly responsible for invalidating normally effective predictive models. Already Mercury is being hammered in the media for not having a contingency plan to handle a four cable failure - something it had described as "unthinkable". Some engineers find climate change pretty unthinkable too. But this could be the same sort of mistake. Whether in this case it will prove to be a career limiting one remains to be seen. It seems prudent to start examining the impacts "the unthinkable" would have on traditional operating parameters. For while engineering is based on science it is more about practicality and sometimes it's better not to wait for exact data before taking precautions. In the meantime, the Ministry for the Environment has set itself the COP-4 meeting in November as a deadline for the firm announcement of a package of measures required under the Kyoto accords on climate change. New Zealand is particularly keen to start a domestic market in emissions rights but whether this, or the low level carbon tax postulated by Treasury prevails, remains to be seen. Like it or not, this year climate change is going to have an effect on the way engineers plan for the future. <HR> </td> </tr> <tr> <td width="30"><img src="/ipenz/images/front/1x1tr.gif" alt="Blank space" width="30" height="50"></td> <td width="160" valign="top" align="left"><img src="/ipenz/images/front/1x1tr.gif" alt="Blank space" width="160" height="50"></td> <td width="20"><img src="/ipenz/images/front/1x1tr.gif" alt="Blank space" width="20" height="50"></td> <td width="550" align="left" valign="top" class="bodya"><img src="/ipenz/images/front/1x1tr.gif" alt="Blank space" width="400" height="50"></td> <td align="right" valign="top" width="250"> </td> </tr> </table> <div id="footer"> © 1996 - 2012 IPENZ </div> </div> </body> </html>