An international expert on solar energy and forestry, John Perlin has lectured extensively on these topics in North America, Europe, Asia, and Australia. Perlin is the author of A Forest Journey: The Story of Wood and Civilization as well as From Space to Earth: The Story of Solar Electricity. Perlin mentors those involved in realizing photovoltaic, solar hot-water, and energy-efficiency technologies at the University of California, Santa Barbara (UCSB), and coordinates the California Space Grant Consortium as a member of UCSB's department of physics.