替代能源

最常被提到的替代能源是太陽能和風力發電. 核四可每年產生 240 億度電力. 太陽能如果要代替核四, 粗略算了一下, 這至少需要 150 平方公里太陽能面板, 相當於百分之五十五的臺北市面積. 臺灣不可能有資金和土地來建造一個如此巨型的太陽城. 

至於風力發電, 雖然風力常被提到是最有可能替代核能的選擇, 但 wind farm 吵得要命, 所以只能建在荒郊野外或近海地區. 風力發電效率僅有6% (30% 的轉換效率乘以20% 的相容於現有穩定電力的傳輸效率). 想要和核四電力相當, 那 wind farm 很可能在近海地區會將臺灣圍得"風洩不通". 美國億萬富翁, T. Boone Pickens, 曾投下巨資在渺無人煙的德州建造一座大型 wind farm. 目標是將電力輸往加州. 這"義舉"也曾讓美國媒體大加吹捧. 但是在兩年多前, 就因電力傳輸問題和價格競爭力問題而打退堂鼓了. 

即使在美國紐約市附近也有一座老舊的核能電廠. 半年前的 Sandy 颶風也曾讓紐約媒體杞人憂天式地擔心 "這個老核電廠經得起吹嗎?" 反核或擁核永遠是歸諸於 "核四安全嗎?" 而不是無謂的意識型態爭執.

Geriatric may be deemed as thief

This week's Business week has an article about Alzheimer's. You may outlive cancer or heart disease, but when you are an octogenarian, the chance to have some degree of Alzheimer's is 50%. Probably Confucian aphorism, "Geriatric may be deemed as thief", has some degree of truth.

Alzheimer's: The Costliest Killer

www.businessweek.com

The disease's overwhelming suffering—and expense—cry out for a greater research effor

備用容量率

最近的核四爭執, 有很多似是而非的數目, 甚至政治語言, 來迷惑一般民眾. 其中之一, 就是"備用容量率", 也就是"機組維修和無法24小時都在發電(如絕大部分的替代能源)和民眾用電有高有低的能源閒置率". "專家"宣稱臺灣的28%備用容量率太高, 所以核四 (約8.6%)可以放棄. 讓我們來看看是否臺灣備用容量率真的是太高?

圖一顯示民國98年(金融海嘯高峰)時, 閒置量確實有28.1%. 但現已低於12%, 低於民國94年制訂的"法定"16%. 圖二顯示備用率和停電或限電次數的關係. 如果閒置率太低, 限電次數太多, 經濟成長呆滯, 那我們是否還要高喊"閒置率太高了?"

再看看核能發電比例. 臺灣的總電力裝置容量為每年2800億度. 核一每年110億度(4%), 核二每年172億度(6.1%), 核三每年166億度 (5.9%), 核四每年240億度 (8.6%). 核一,二,三總共貢獻16%. 但因核能非常穩定, 所以核能容量雖佔16%, 但核能在日常發電上平均佔到22%. 核一和核二在六年和九年後退役, 到時我們是否可以再高喊"我們完全不需要核能"的"神聖囗號"?

Trip to China

Just came back from 2-week tour in Taiwan including 5 days in Beijing and Tianjin. It was an indelible trip to China. 5-day trip to China included climbing ( or even scrambling) steep Great Wall (居庸關長城), visiting sepulchral subterraneanemperor mausoleum of Ming Dynasty (定陵 in 明十三陵), immense Tiananmen Square(天安門廣場), imposing multitudinous imperial edifices in Forbidden City (紫禁城故宮), dignified Heaven Temple (天壇), engaging Summer Palace (頤和園), riding high-speed train from Tianjin to Beijing, experiencing short ride of Beijing subway from 青花瓷車站, enjoying the delectable 全聚德's roasted duck and 東來順's dip-and-boil mutton, strolling casually on the wide and car-free 王府井大街 and its adjacent crowded and bustling night market (東華門夜市), watching face-changing show and son-et-lumiere KungFu show (功夫聲光秀), riding tricycle to wind through the rabbit warren (胡同) in Beijing, staying in the luxurious 5-star hotels (St. Regis in Tianjin and Sofitel in Beijing), swimming in their garden-esque swimming pools with simulacrum starred canopy, riding a horse wagon amid the quaint colonial buildings (馬車遊第五大道) with the background of high-rise skyscrapers in Tianjin, sipping coffee in the exotic Italy-esque street(義大利風情街) in Tianjin, in-person experience of BirdNest and WaterCube in Beijing, first-time experience in the "shopping-encouraged" pearls, tea-leaves and silks stores with flabbergasted price tags. One of the eye-catching scenes in Tianjin and Beijing is "high-rise cranes are everywhere". It is probably not surprising since China consumes 53% of cement worldwide. Very pleasant first-time experience in China; all sunny days, no sandstorm, non-repellent air quality and reasonably mild temperature.

Live off the fat of the welfare land

It would be my day dream to live in Denmark without any work (and perfectly healthy and young) and still can collect US $2700/month for 20 years from government since age 16 as reported by NY Times. (However, my working companions in Denmark need to pay 56.5% tax and probably get less income as I do!! What a dream!)

Danes Rethink a Welfare State Ample to a Fault

www.nytimes.com

With little fuss or political protest — or notice abroad — Denmark has been at work overhauling entitlements, trying to prod Danes into working more or longer or both.

Taiwan's nuclear power plant 4 核四的安全規格

最近閱讀很多有關核能安全的資料 (包括 84 頁的日本福島核電廠危機的專業報告, 福島核電廠的檢討會議報告, IEEE Spectrum 的一系列核能安全專題報導, WiKipedia 的各式核能電廠的介紹 和紐約時報一些核能安全的專題報導). 我的結論是核四的安全規格絕對比核一或日本福島核電廠的安全規格高很多.

姑且不談一些專業安全項目諸如自動減壓閥,氫爆的產生,圍阻牆的設計等等, 我們將只是專注在循環冷卻水所需要的持續電力這個主題上, 這也是造成美國三哩島事件, 蘇俄 Chernobyl 事件和日本福島事件會發生的最重要因素. 日本在2011年發生大地震瞬間, 福島電廠的全部反應爐皆立刻啟動降下控制棒的緊急措施. 核子反應器立刻中止作用, 但核子分裂仍持續慢慢地減低反應, 但先決條件是冷卻水必須持續供應數個星期, 才不會讓燃料棒熔解而產生氫氣爆炸. 在福島事件上, 地震發生55分鐘後, 14公尺高的海嘯巨浪淹沒了全部13座柴油發電機. 蒸汽渦輪泵浦雖立刻啟動, 但蒸汽渦輪仍需電池供應的直流電才能運作. 福島電廠的設計(和核一同樣的設計)僅能供應電池4小時(核四為8小時). 當電池用盡, 冷卻水不再循環, 高溫的燃料棒開始蒸發反應器中的冷卻水. 當冷卻水水位下降到使燃料棒外露時, 燃料棒外層的塗料, Zirconium, 開始氧化而產生氫氣. 當氫氣碰到氧氣就會爆炸. 福島的六個反應器幾乎都有不同程度的氫爆問題(美國三哩島也是同樣問題). 追根究底, 就是備用柴油發電機全部浸水和電力驅動的控制閥全部停擺.

核四不應該會有這個問題因為 (1)核四柴油發電機皆放在高處, 如附圖. (2)臺灣東部地形陡峭, 海嘯高度不應超過4公尺. (3)核四除了核一有的柴油發電機和緊急電池驅動蒸汽泵浦外, 還有一個放在高處的可運轉七天的燃氣渦輪發電機, 如附圖. (4)當電池用盡且完全彈盡援絕時, 核一只能撐八小時燃料棒就會開始熔解, 但核四可撐三天 (5)核四的第一層圍阻牆比核一堅固很多, 而且核四有三層圍阻牆但核一僅有兩層, 所以核四在氫爆狀況下不容易外洩輻射物質. (6)核四設計可撐0.4g震動(8級地震?) 核一,二,三只可撐0.3g震動.

不論反核四與否, 理性的評估態度應該是 "檢視在往後半年核四驗收的結果. 如果符合當年奇異公司設計先進式沸水反應器 (ABWR) 的規格, 那就應該讓核四運轉. 如果有重大缺失, 那反核四就真的是等於捍衛家園的神聖理念". 另外, 我們也祈禱在往後的六年內, 安全性較差的核一(和日本福島核電廠同型)不會出現重大的差錯. (註: 就算核四商轉, 全民也要監督臺電核能危機處理的能力. 你能相信日本福島核電廠的員工竟然從來沒有作過 "完全沒電了怎麼辦" 的演習!! )

Competence is more important academic degree

Latest issue of TIME magazine has a cover story, "Made in the USA", which basically confirms what I always believe, "every dog has its day" (風水輪流轉). US worker's salary is 7 times of Chinese worker's while US worker's productivity is 3.5 times of Chinese worker's. In the last several years, Chinese workers have been demanding higher pay as is evident from the 13% mandated increase in minimum wage while US workers are willing to settle to lower paycheck. The results: decreasing offshoring and increasing inshoring in the US. However, there is one caveat in the increasing US job opportunity. Most of the increasing jobs in the US require 2-4 years in artisan skills. Another proof of the "competence is more important than academic degree" (學力勝於學歷).