Renewable energy technologies such as solar cells and wind turbines do not offset U.S. fossil fuel use and could in fact accelerate it, a researcher says. University of California, Berkeley, visiting scholar Ozzie Zehner has written a book, \"Green Illusions,\" that argues building more solar cells and wind turbines could actually increase fossil fuel use unless nations take other steps to avoid a \"rebound\" effect. While many assume solar cells and wind farms will displace coal use and lower carbon dioxide levels, Zehner argues that subsidizing renewable energy merely expands energy supplies, which exerts a downward pressure on prices. Energy demand subsequently increases, he said. \"This brings us right back to where we started: high demand and so-called insufficient supply,\" says Zehner. \"Historically, we\'ve filled that added demand by building more coal-fired power plants, not fewer. \"We create an energy boomerang,\" Zehner said in a PBS interview. \"The harder we throw energy into the grid, the harder demand comes back to hit us on the head. More efficient solar cells, taller wind turbines, and advanced biofuels are all just ways of throwing harder.\" Countries will have to institute socioeconomic innovations rather than technical ones to avoid the boomerang effect, he said, including lower per-capita energy consumption, energy taxes that would increase over time, and binding long-term plans to improve building and equipment efficiency. \"The United States meets none,\" of these innovations, Zehner said. \"In fact, in countries such as the United States, with dismal efficiency, sprawling suburbs, a growing population, and high rates of material consumption, renewable energy technologies do the most harm as they perpetuate energy-intensive modes of living.\"