"Is the search page, Blackle.com, really an energy efficient alternative to Google? The theory is websites with black background save energy. That claim is based on an assumption that "a given monitor requires more power to display a white (or light) screen than a black (or dark) screen. Is this a blatant green washed marketing ploy, or an earnest energy saving tweak for something we use every day?
To find out, PCSTATS hooked up an Extech Power Analyzer to a 19" CRT and a 19" LCD. One explorer window, set to full screen (1280x1024) was opened to each of the following websites. Blackle's claims appear to hold water, although the difference is just 17.7W and 3.8W for CRT and LCD respectively."