I just received this terse question from a reader: “What’s the ROI (return on investment) on solar thermal?”
I responded, hoping to prompt more discussion: “That’s an interesting but impossible question to answer. What is the nature of your interest in the subject, if I may ask?”
I post this brief conversation because it’s indicative of two much larger and incredibly important issues:
1) Computing the ROI for investors in new technologies like these is impossible, as no one can pick the winners from the losers at this point. Personally, I’m betting on solar thermal, and, though many agree, there are far greater minds than mine that don’t see it this way.
2) Not to get too flippant, but what’s the ROI on saving our civilization from destruction? According to Lester Brown, whom the Washington Post calls “one of the world’s most influential thinkers,”
Ice is melting so fast that even climate scientists are scrambling to keep up with the shrinkage of ice sheets and glaciers. The melting of the earth’s largest ice sheets—Greenland and West Antarctica—would raise sea level dramatically. If the Greenland ice sheet were to melt entirely, it would raise sea level 23 feet. Melting of the West Antarctic ice sheet, the most vulnerable portion of the Antarctic ice because of its exposure to both warming air and warming ocean water, would eventually raise sea level 16 feet. Many of the world’s coastal cities would be under water; over 600 million coastal dwellers would be forced to move.
Solar thermal holds the single greatest promise of clean, abundant, inexpensive energy — in the absence of which mankind will be unable to make its way across these next critical 50 years.
I’m sure this latter point was not contemplated in the reader’s question, but some folks may find it worth considering.