Profitable solutions to climate, oil, and proliferation.

Protecting the climate is not costly but profitable (even if avoided climate change is worth zero), mainly because saving fuel costs less than buying fuel. The two biggest opportunities, both sufficiently fast, are oil and electricity. The US, for example, can eliminate its oil use by the 2040s at an average cost of $15 per barrel ($2000), half by redoubled efficiency and half by alternative supplies, and can save three-fourths of its electricity more cheaply than operating a thermal power station.