A lot of commentators weighed in on “Caritas in Veritate” (Charity in Truth) – the encyclical that Pope Benedict delivered last week. Most of the discussion focused on the Pope’s coherent (and, some said, relatively progressive) pronouncements on social justice, poverty, and the erosion of ethical business and political practices in wealthy and well as poor countries.

But as a few observers also noted, the pontiff directly addressed environmental concerns, including the use of nonrenewable resources to produce energy.

“The technologically advanced societies can and must lower their domestic energy consumption, either through an evolution in manufacturing methods or through greater ecological sensitivity among their citizens,” he wrote. “It should be added that at present it is possible to achieve improved energy efficiency while at the same time encouraging research into alternative forms of energy.”

The Vatican, in fact, has been developing its own green strategies in very secular terms. Last November, it began installing a 300 mW solar power system on the Paul VI auditorium. Other renewable-energy systems are planned for elsewhere in and around Vatican City – enough to power 20% of its operation by 2020, a target that is in line with energy conservation goals set by the European Union.