It and two other German companies, Conergy and SolarWorld, are particularly indignant that German subsidies were the main source of demand for solar panels until recently.
Software created by Brighter Planet analyzes cardholder purchases such as flights, car rentals, hotel reservations, and translates them into carbon dioxide emissions.
Upon departing your island getaway, make sure your purchases are easily accessible in case your home country's customs officials request an inspection.
Provisions available in local shops have to be flown into Nunavut on one of the most costly air networks in the world, or brought by supply ship during the few ice-free weeks of summer.
"As people develop their higher levels of disposable income, they want to treat themselves," he said. "they do not want to just buy Tesco Value shower gel."
Firms responsible for emissions, including utilities and oil producers, would either have to cut them or compete to buy a steadily shrinking number of permits.