Tři starší články, které jsme uváděli již dříve, jsou:
Výmluvné jsou ale i úryvky z archivu DarkSky-listu o nápravě osvětlovací soustavy v Calgary:
Calgary's decision is unique among recent light-pollution initiatives. It calls for the changing of all residential street lighting immediately; most cities replace their fixtures gradually, as the old ones malfunction. But what the city spends now it will recover later -- government officials project that each year Calgary can expect to save $2.1 million Canadian ($1.4 million US) in electricity. Even if energy prices drop to their previous levels, it will take only 6.5 years to recoup the project's $7.8 million ($5.2 million US) cost.
You note that Calgary, Alberta, has embarked on a program to convert all streetlights to fully shielded types and simultaneously reduce wattage by half. A memorandum prepared by the Calgary Police Service reached this conclusion: "It may have been argued that common sense dictated that greater lighting translated into greater safety. However, we now know this is not true."